Homepage of Priv.-Doz. Dr. Thomas Dreibholz

Contact

Priv.-Doz. Dr. Thomas Dreibholz
Researcher and Developer for Computer Networks

💻 Internet

📧E-Mail:
🔑OpenPGP Key:	21412672518D8B2D1862EFEF5CD5D12AA0877B49
🖖OpenPGP Fingerprint:	2141 2672 518D 8B2D 1862 EFEF 5CD5 D12A A087 7B49

🌍Simula Homepage:	https://www.simula.no/people/dreibh
🌏Personal Homepage:	https://www.nntb.no/~dreibh

🕸️LinkedIn:	https://www.linkedin.com/in/thomas-dreibholz-9b555337
🕸️ResearchGate:	https://www.researchgate.net/profile/Thomas_Dreibholz
🕸️ORCID:	https://orcid.org/0000-0002-8759-5603

📦GitHub:	https://github.com/dreibh
📦BitBucket:	https://bitbucket.org/dreibh
📦GitLab:	https://gitlab.com/dreibh
📦Ubuntu Launchpad:	https://launchpad.net/~dreibh
📦Fedora COPR:	https://copr.fedorainfracloud.org/coprs/dreibh/ppa

🏢 Visiting Address

Priv.-Doz. Dr. Thomas Dreibholz
Simula Metropolitan Centre for Digital Engineering A/S
Centre for Resilient Networks and Applications (CRNA)
Pilestredet 52
N-0167 Oslo
🇳🇴Norway

🌐GPS: 59.9223550°N, 10.7322170°E

🏤 Postal Address

Priv.-Doz. Dr. Thomas Dreibholz
Simula Metropolitan Centre for Digital Engineering A/S
c/o OsloMet – storbyuniversitetet
Postboks 4 St. Olavs plass
N-0130 Oslo
🇳🇴Norway

📜 My Curriculum Vitae

📄 My Research Projects

GAIA – Cyber Sovereignty

The goal of the GAIA project, in collaboration with the Norwegian Institute of International Affairs (NUPI), is to undertake crucial multidisciplinary research that aims to develop new methods, metrics and frameworks for understanding the complex interplay between digital vulnerabilities and national autonomy. The research is funded by the Research Council of Norway (Forskningsrådet).

For more details on GAIA, see GAIA – Cyber Sovereignty!

5G-VINNI – 5G Verticals Innovation Infrastructure

5G-VINNI will accelerate the uptake of 5G in Europe by providing an end to end (E2E) facility that lowers the entry barrier for vertical industries to pilot use cases and supports the pilots as the infrastructure evolves. The project is funded by the European Union as part of the Horizon 2020 programme.

For more details on 5G-VINNI, see 5G-VINNI – 5G Verticals Innovation Infrastructure!

NorNet – A Real-World, Large-Scale Multi-Homing Testbed

Multi-homing denotes the simultaneous connection of endpoints (e.g. cloud server, smartphone, etc.) to multiple Internet Service Providers (ISP). That is, the endpoints remain reachable even when some of the ISPs have problems (e.g. malfunction of hardware or break of cables). Besides the redundancy aspect, multi-homing can also provide load sharing among the access links, in order to increase the application bandwidths. The fast-growing need for and deployment of resilience-critical applications makes large-scale testing and evaluation in realistic Internet setups necessary. NorNet is a platform for such experiments, providing programmable nodes distributed over Norway and – in the near future – further nodes distributed all over the world.

For more details on NorNet, see NorNet – A Real-World, Large-Scale Multi-Homing Testbed!

MELODIC – Multi-Cloud Execution-Ware for Large-scale Optimised Data-Intensive Computing

The vision of the MELODIC project is to enable federated cloud computing for data-intensive applications. Furthermore, it provides the user with an easy-to-use, unified cloud environment, which hides the complexity of a multi-cloud. Particularly, MELODIC combines OpenStack-based cloud systems with the geographic distribution of NorNet sites to provide a realistic test platform.

For more details on MELODIC, see MELODIC – Multi-Cloud Execution-Ware for Large-scale Optimised Data-Intensive Computing!

HENCSAT – Highly Efficient Network Coding for Satellite Applications Testbed

HENCSAT investigates the benefits of combining Highly Efficient Network Coding (HEVC, H.265) video encoding with torrent transmission and multi-path transport. Goal is to optimise communication services – particularly also using satellite communication – for the communication with unmanned aerial vehicles (UAV) and vehicle convoys in remote areas.

For more details on HENCSAT, see HENCSAT – Highly Efficient Network Coding for Satellite Applications Testbed!

NEAT – A New, Evolutive API and Transport-Layer Architecture for the Internet

The NEAT project wants to achieve a complete redesign of the way in which Internet applications interact with the network. Goal is to allow network services offered to applications – such as reliability, low-delay communication or security – to be dynamically tailored based on application demands, current network conditions, hardware capabilities or local policies. NEAT therefore particularly also supports multi-path communication with SCTP and Multi-Path TCP (MPTCP).

For more details on NEAT, see NEAT – A New, Evolutive API and Transport-Layer Architecture for the Internet!

Stream Control Transmission Protocol (SCTP)

The Stream Control Transmission Protocol (SCTP) is an advanced Transport Layer protocol which may some day replace TCP. Focus of my research on SCTP is the optimisation of Concurrent Multipath Transfer (CMT), which means to simultaneously utilise multiple paths within the network to increase the application data throughput. This particularly also includes topics like congestion control and the fairness of resource sharing. Besides my research work on CMT-SCTP, I am also involved in the IETF standardisation process of this protocol extension.

For more details on my project, see The SCTP Project Page!
For more details on my habilitation, see My Habilitation!

Reliable Server Pooling (RSerPool)

Reliable Server Pooling (RSerPool) denotes a new IETF standard for the management of server pools and sessions with these pools. This standard provides both, high reliability (by redundancy of servers) as well as load balancing (by appropriate distribution of requests to the servers in a pool). For that purpose, RSerPool works on the Session Layer of the OSI model. I am actively involved in the IETF standardisation of RSerPool, in form of my Open Source implementation rsplib as reference implementation of the IETF Working Group, my simulation model rspsim in OMNeT++, as well as various research works and IETF contributions.

For more details on my project, see The rsplib Project Page!

Flow Routing

Flow routing is a novel concept for efficient high-speed routing. Combining the flow routing concept with Quality of Service (QoS), a network can efficiently cope with the requirements of modern multimedia applications. The main goal of our flow routing project is to develop, evaluate and finally also standardise a QoS concept for assuring the bandwidth requirements of multimedia applications – requiring only minimal signalling overhead.

For more details on this project, see The Flow Routing Project Page!

💾 My Software Projects

2015 – ...: HiPerConTracer – High-Performance Connectivity Tracer
HiPerConTracer is an advanced Ping/Traceroute service. It performs regular Ping and Traceroute measurements over IPv4 and IPv6 among sites. Results are exported into an SQL or NoSQL database. Analysis scripts can then access this data for research on network connectivity and resilience, as well as for visualising the connectivity within the Internet.
2011 – ...: The RTP Audio NextGen System
RTP Audio NextGen is an audio streaming system with support for SCTP as well as UDP transport. It is a highly advanced and reworked version of the former RTP Audio system with support for SCTP streams and SCTP partial reliability. Furthermore, it also contains a QoS management interface. RTP Audio NextGen may use layered encoding, that is the audio quality may be adapted according to the QoS that is achievable in the network. The main purpose of this tool is to support transport protocol and QoS research, by providing a realistic application for performance testing.
2002 – ...: The rsplib Implementation of the Reliable Server Pooling Framework
rsplib is the Open Source implementation of the IETF's Reliable Server Pooling (RSerPool, RFC 5351) framework. The implementation is written in ANSI-C and C++. Currently, it supports Linux, FreeBSD, MacOS X and Solaris. Its intention is to validate the RSerPool drafts currently under standardisation by the IETF and to verify results from my simulative research. As part of my RSerPool research in the context of my Ph.D. thesis, multiple Internet Drafts have been contributed to the IETF's standardisation process. Meanwhile, rsplib has become the IETF RSerPool Working Group's reference implementation of RSerPool.
2009 – ...: NetPerfMeter – A Tool for TCP/MPTCP/UDP/SCTP/DCCP Network Performance Metering
NetPerfMeter is a network performance meter for the UDP, TCP, MPTCP, SCTP and DCCP transport protocols over IPv4 and IPv6. It simultaneously transmits bidirectional flows to an endpoint and measures the resulting flow bandwidths and QoS. The results are written as vector and scalar files. The vector files can be used to create PDF plots of the results.
2009 – ...: BibTeXConv – A BibTeX File Converter
BibTeXConv is a BibTeX file converter which allows to export BibTeX entries to other formats, including customly defined text output. Furthermore, it provides the possibility to check URLs (including MD5, size and MIME type computations) and to verify ISBN and ISSN numbers.
2007 – ...: SimProcTC – A Tool-Chain for Simulation Processing with OMNeT++
SimProcTC is a model-independent, flexible and powerful tool-chain for the setup, parallel run execution, results aggregation, data analysis and debugging of OMNeT++-based simulations, using GNU R and other Open Source software under Linux and FreeBSD. It optionally utilises the Reliable Server Pooling (RSerPool) implementation rsplib for easily setting up simulation processing pools for distributed execution of simulation runs.
2001 – ...: Socket API implementation for the SCTP Library sctplib
sctplib is an Open Source userland implementation of the Stream Control Transmission Protocol (SCTP, RFC 4960). The Socket API – realised in C++ and ANSI-C – implements the Unix Socket calls (e.g. bind(), connect(), setsockopt(), recvmsg(), ...) for sctplib. Both packages are multi-platform and support Linux, FreeBSD, MacOS X and Solaris. This project has been a cooperation between the University of Duisburg-Essen, Computer Networking Technology Group at the Institute for Experimental Mathematics and Siemens.
2003 – ...: SlideShow – A Program to Create HTML-based Slideshows
SlideShow is a C++-based Open Source Linux application generating standards-compliant XHTML-1.1 presentations from a set of image files. It has been created to easily generate online photo albums, including JavaScript-based slideshows.
2002 – ...: SubNetCalc – An IPv4/IPv6 Subnet Address Calculator
SubNetCalc is a C++-based Open Source program to print various information about a given IPv4 or IPv6 address. It can also identify the address type and extract additional information from the address. Furthermore, it can be used to generate IPv6 Unique Local prefixes.
2003: The Fractal Generator Project
FractalGenerator is a KDE-based Open Source program under Linux – written in C++ – to compute fractal images (e.g. the Mandelbrot set). The size of the calculated images is only limited by the computer's virtual memory. This program has been developed as an example for object-oriented programming and creating Qt/KDE applications for the University of Duisburg-Essen's Linux Workshop in 2003.
2000 – 2001: The RTP Trace System
An Open Source, Linux-based real-time network streaming test system that uses traces of various media types (MPEG 1/2, H.263, MP3, ...). It is realised in C++. This project is part of my Masters Thesis at the University of Bonn, Germany.
1999 – 2001: The RTP Audio System
A Linux-based Open Source real-time network audio streaming system, supporting DiffServ, IPv6 and IPv6 flowlabels. Server and clients have been written in C++, a Java client is realised using JNI (Java Native Interface). The system has been a study project at the University of Bonn, Germany. My responsibility has been the implementation of the client/server transmission system itself, including the media codecs and the RTP protocol as well as the client GUI based on the Qt Toolkit.
2000: Prüfungsamt-Projekt – A Student and Exam Management Tool
A SQL-based, Open Source database application under Linux, written in C++, using the Qt GUI Toolkit and PostgreSQL, to simplify the work of the University's exams office (Prüfungsamt) using database transactions and triggers. It has been a study project at the University of Bonn, Germany. My responsibilities have been the GUI realisation and the SQL trigger implementation.
1994 – 2000: The MusicBox Project
MusicBox is an audio CD playing application and management system for AmigaOS, realised in C. In particular, this software uses the SCSI interface to take advantage of all audio playing capabilities of the CD-ROM drive (e.g. channel selection, volume control, position information). This software has been shareware and is now Open Source.
1998 – 1999: The RandGraph Project
The continuation of the TriGraph project (see below): the random generation of different types of graphs and their visualisation, realised in C++ using the Qt GUI Toolkit. RandGraph has been created as optional part of my theory seminar's subject at the University of Bonn, Germany, in order to illustratively demonstrate the theoretic contents of my talk.
1999: PuMa – A Publication Manager
A Java/JDBC/SQL-based, Open Source database application (MySQL) to manage a library using a web browser (via Java Servlet). It has been a study project at the University of Bonn, Germany. My responsibilities have been the SQL database schema, a test data generator (written in C++) and an SMTP-based e-mail notification component (realised in Java). I have partially continued this project on my own and extracted some components for later reuse in lecture exercises at the University of Bonn.
1999: The TriGraph Project
A C++-based system to generate lists of non-isomorphic, trivalent graphs. In particular, this package includes a Qt/KDE-based viewer to display and print the generated graph lists. It has been part of a study project at the University of Bonn, Germany. My responsibilities have been the graph storage and file I/O operations as well as the GUI component.
1999: TDMouse – A Serial Mouse Driver for AmigaOS
An Open Source driver for serial mice of multiple vendors under AmigaOS, written in C. It has been written in order to allow using a standard PC mouse with a Commodore Amiga computer.
1996 – 1997: WarpEd – A Multi-Platform Text Editor
A cross-platform text editor for Linux and OS/2 Warp, written in C++. The main design criteria of this Open Source application is the easy portability to other platforms, in order to allow using the same text editor application on every platform.
1995 – 1997: The MultiDesktop Project
An Open Source GUI library for AmigaOS, written in C. It has been developed in order to easily create complex and consistent user interfaces for AmigaOS programs. In particular, it also includes bindings to other programming languages.
1992 – 1997: The ATUtilities Project
A replacement for the Commodore Amiga 2086/2286/2386 Bridgeboard driver software. It is the result of a reverse engineering of the original drivers in order to overcome their limitations. The system is written in C, with some hardware-near parts in Assembler. This software has been shareware and is now Open Source.
1992: TerrainEd – A Terrain Editor for Sim City
TerrainEd is a terrain editor for the game Sim City. This software was shareware and is Open Source now.
1992: ConvertFDPlus – An Amiga FD file converter
ConvertFDPlus is a converter for Amiga FD files (library descriptions). The program supports AmigaBASIC BMAP files, Assembler offset files and Aztec-C 3.4a library interfaces. ConvertFDPlus is Open Source.
1990 – 1991: TurboDevice – A Reset-Resident RAM Disk Driver for AmigaOS
An Open Source driver for a reset-resident RAM disk under AmigaOS, written in C with some speed-critical functions in Assembler. Parts of this driver have been reused by the Amiga Research Operating System (AROS) project.

🖋️ My Publications

The complete BibTeX references in a single file can be found here!

2023

Mazumdar, Somnath and Dreibholz, Thomas: ``Proactive Resource Orchestration Framework for Cloud/Fog Platform´´ (🇬🇧), in Proceedings of the 28th IEEE Symposium on Computers and Communications (ISCC), Tunis/Tunisia, July 2023, [BibTeX, XML].

Keywords: Cloud, Fog, Resource Allocation, Orchestration, Prediction
Abstract: Cloud computing makes complex computing an off-premise activity by offering software- and hardware-based services using standard security protocols over the Internet. It has been seen that the cloud is not ideal for latency-sensitive applications. Thanks to the current growth of network communication and infrastructure, fog adds a computing resource delegation layer between the user and the cloud. Fog aims to improve latency-sensitive applications support. Here, we propose one unified, proactive resource orchestration framework from a cloud/fog service provider perspective. The framework consists of a predictor and a resource allocator module. Users subscribe to these resources to execute their applications. The framework does not require application-specific information and is modular, meaning a service provider can customise each module. We have presented the framework prototype by showing each module's simulated performance results using the parameters of our cloud/fog research test bed.
Bjørnstad, Steinar; Ali, Jameel; Dreibholz, Thomas and Sæthre, Erik: ``A Scalable Data Collection System for Continuous State of Polarisation Monitoring´´ (🇬🇧), in Proceedings of the 23rd International Conference on Transparent Optical Networks (ICTON), Bucharest/Romania, July 3, 2023, [BibTeX, XML].

Abstract: Our dependency on the telecommunication infrastructure is continuously increasing, as different infrastructures – such as energy and telecommunication – now have mutual dependencies. This calls for increased monitoring of the fibre network, which is a highly critical part of the infrastructure. State of Polarisation (SoP) of light propagating through fibre transmission systems is impacted by any vibrations and mechanical impacts on the fibre. By continuously monitoring the SoP, any unexpected movements of a fibre along a fibre-path may be traced. Movements may be caused by e.g. work in node-rooms impacting patch-cords, trawlers or other types of sub-sea equipment touching or hooking into sub-sea fibre cables, digging close to a fibre-cable, or geophysical phenomena like earthquakes. In this paper, we describe a low-cost, scalable system for SoP monitoring and give examples of patterns monitored in different types of fibre infrastructures. The monitoring system consists of single-unit rack-mount instruments connected to taps from live optical transmission signals. Each instrument has local storage for 1-2 years of data, and is periodically automatically uploading data to a server for backup and data-access purposes. Examples of observed patterns are impact from a thunderstorm on a Fibre-To-The-Home (FTTH) cable, 50 Hz on a fibre-cable spun around a high-voltage power air-cable, as well as animal impact on a patch-cord.
Dreibholz, Thomas and Mazumdar, Somnath: ``Towards a Lightweight Task Scheduling Framework for Cloud and Edge Platform´´ (PDF, 4020 KiB, 🇬🇧), in Internet of Things, vol. 21, Elsevier, DOI 10.1016/j.iot.2022.100651, ISSN 2542-6605, April 2023, [BibTeX, XML].

Keywords: Cloud, Edge, Framework, Placement, Task
Abstract: Mobile devices are becoming ubiquitous in our daily lives, but they have limited computational capacity. Thanks to the advancement in the network infrastructure, task offloading from resource-constrained devices to the near edge and the cloud becomes possible and advantageous. Complete task offloading is now possible to almost limitless computing resources of public cloud platforms. Generally, the edge computing resources support latency-sensitive applications with limited computing resources, while the cloud supports latency-tolerant applications. This paper proposes one lightweight task-scheduling framework from cloud service provider perspective, for applications using both cloud and edge platforms. Here, the challenge is using edge and cloud resources efficiently when necessary. Such decisions have to be made quickly, with a small management overhead. Our framework aims at solving two research questions. They are: i) How to distribute tasks to the edge resource pools and multi-clouds? ii) How to manage these resource pools effectively with low overheads? To answer these two questions, we examine the performance of our proposed framework based on Reliable Server Pooling (RSerPool). We have shown via simulations that RSerPool, with the correct usage and configuration of pool member selection policies, can accomplish the cloud/edge setup resource selection task with a small overhead.
URL: https://www.simula.no/file/iot2023pdf/download
MD5: b6aef5ff3b1bbf61cd4c03c8acb60222
Čičić, Tarik; Kvalbein, Amund; Al-Selwi, Anas Saeed; Michelinakis, Foivos Ioannis and Dreibholz, Thomas: ``Norske mobilnett i 2022 – Tilstandsrapport fra Centre for Resilient Networks and Applications´´ (PDF, 8343 KiB, 🇳🇴), Simula Metropolitan Center for Digital Engineering, Centre for Resilient Networks and Applications (CRNA), ISBN 978-82-92593-38-7, Oslo/Norway, April 27, 2023, [BibTeX, XML].

Abstract: Denne rapporten er utarbeidet av Center for Resilient Networks and Applications (CRNA), som er en del av Simula Metropolitan Center for Digital Engineering. CRNA driver grunnleggende forskning innen robusthet og sikkerhet i nettverk med mandat og finansiering fra Kommunal- og moderniseringsdepartementet. Senteret produserer en årlig rapport om tilstanden i norske mobilnett. Årets rapport er den tiende i rekken
URL: https://www.simulamet.no/sites/default/files/norske_mobilnett2022.pdf
MD5: 4b4c5475aa8872b240ea63c4fc262012
Dreibholz, Thomas: ``An IPv4 Flowlabel Option´´ (TXT, 18 KiB, 🇬🇧), Internet Draft draft-dreibholz-ipv4-flowlabel-37, IETF, Individual Submission, March 26, 2023, [BibTeX, XML].

Abstract: This draft defines an IPv4 option containing a flowlabel that is compatible to IPv6. It is required for simplified usage of IntServ and interoperability with IPv6.
URL: https://tools.ietf.org/id/draft-dreibholz-ipv4-flowlabel-37.txt
MD5: 0c2f5eccc1283ef5359a1a0c1d476dcb
Dreibholz, Thomas: ``Applicability of Reliable Server Pooling for Real-Time Distributed Computing´´ (TXT, 19 KiB, 🇬🇧), Internet Draft draft-dreibholz-rserpool-applic-distcomp-34, IETF, Individual Submission, March 26, 2023, [BibTeX, XML].

Abstract: This document describes the applicability of the Reliable Server Pooling architecture to manage real-time distributed computing pools and access the resources of such pools.
URL: https://tools.ietf.org/id/draft-dreibholz-rserpool-applic-distcomp-34.txt
MD5: 7173b86f73be573ee306801367aebbc6
Dreibholz, Thomas and Pulinthanath, Jobin: ``Applicability of Reliable Server Pooling for SCTP-Based Endpoint Mobility´´ (TXT, 17 KiB, 🇬🇧), Internet Draft draft-dreibholz-rserpool-applic-mobility-33, IETF, Individual Submission, March 26, 2023, [BibTeX, XML].

Abstract: This document describes a novel mobility concept based on a combination of SCTP with Dynamic Address Reconfiguration extension and Reliable Server Pooling (RSerPool).
URL: https://tools.ietf.org/id/draft-dreibholz-rserpool-applic-mobility-33.txt
MD5: f2ad96418703abea8a03d7bafcf40386
Dreibholz, Thomas and Zhou, Xing: ``Definition of a Delay Measurement Infrastructure and Delay-Sensitive Least-Used Policy for Reliable Server Pooling´´ (TXT, 18 KiB, 🇬🇧), Internet Draft draft-dreibholz-rserpool-delay-31, IETF, Individual Submission, March 26, 2023, [BibTeX, XML].

Abstract: This document contains the definition of a delay measurement infrastructure and a delay-sensitive Least-Used policy for Reliable Server Pooling.
URL: https://tools.ietf.org/id/draft-dreibholz-rserpool-delay-31.txt
MD5: f5f65073d2c4b106beb5fb24cf1da0a4
Dreibholz, Thomas: ``Handle Resolution Option for ASAP´´ (TXT, 13 KiB, 🇬🇧), Internet Draft draft-dreibholz-rserpool-asap-hropt-32, IETF, Individual Submission, March 26, 2023, [BibTeX, XML].

Abstract: This document describes the Handle Resolution option for the ASAP protocol.
URL: https://tools.ietf.org/id/draft-dreibholz-rserpool-asap-hropt-32.txt
MD5: 0b2a091b9b836981fb5d8450d7aaa0b5
Dreibholz, Thomas: ``Ideas for a Next Generation of the Reliable Server Pooling Framework´´ (TXT, 16 KiB, 🇬🇧), Internet Draft draft-dreibholz-rserpool-nextgen-ideas-19, IETF, Individual Submission, March 26, 2023, [BibTeX, XML].

Abstract: This document collects some idea for a next generation of the Reliable Server Pooling framework.
URL: https://tools.ietf.org/id/draft-dreibholz-rserpool-nextgen-ideas-19.txt
MD5: 3ec42e198926f71212b83858201bc44d
Dreibholz, Thomas: ``Ideas for a Next Generation of the Stream Control Transmission Protocol (SCTP)´´ (TXT, 17 KiB, 🇬🇧), Internet Draft draft-dreibholz-tsvwg-sctp-nextgen-ideas-17, IETF, Individual Submission, March 26, 2023, [BibTeX, XML].

Abstract: This document collects some ideas for a next generation of the Stream Control Transmission Protocol (SCTP) for further discussion. It is a result of lessons learned from more than one decade of SCTP deployment.
URL: https://tools.ietf.org/id/draft-dreibholz-tsvwg-sctp-nextgen-ideas-17.txt
MD5: 2c1319f88c4fb7631dbb89d4300acf0b
Dreibholz, Thomas; Coene, Lode and Conrad, Phillip T.: ``Reliable Server Pooling Applicability for IP Flow Information Exchange´´ (TXT, 16 KiB, 🇬🇧), Internet Draft draft-coene-rserpool-applic-ipfix-20, IETF, Individual Submission, March 26, 2023, [BibTeX, XML].

Abstract: This document describes the applicability of the Reliable Server Pooling architecture to the IP Flow Information Exchange using the Aggregate Server Access Protocol (ASAP) functionality of RSerPool only. Data exchange in IPFIX between the router and the data collector can be provided by a limited retransmission protocol.
URL: https://tools.ietf.org/id/draft-coene-rserpool-applic-ipfix-20.txt
MD5: 65ad43cb7053bce7af69f746b66a7409
Dreibholz, Thomas and Tüxen, Michael: ``Reliable Server Pooling (RSerPool) Bakeoff Scoring´´ (TXT, 19 KiB, 🇬🇧), Internet Draft draft-dreibholz-rserpool-score-32, IETF, Individual Submission, March 26, 2023, [BibTeX, XML].

Abstract: This memo describes some of the scoring to be used in the testing of Reliable Server Pooling protocols ASAP and ENRP at upcoming bakeoffs.
URL: https://tools.ietf.org/id/draft-dreibholz-rserpool-score-32.txt
MD5: 508eeacec0a41d0ac4fc0f62fbbcfdf0
Dreibholz, Thomas; Becke, Martin and Adhari, Hakim: ``SCTP Socket API Extensions for Concurrent Multipath Transfer´´ (TXT, 13 KiB, 🇬🇧), Internet Draft draft-dreibholz-tsvwg-sctpsocket-multipath-26, IETF, Individual Submission, March 26, 2023, [BibTeX, XML].

Abstract: This document describes extensions to the SCTP sockets API for configuring the CMT-SCTP and CMT/RP-SCTP extensions.
URL: https://tools.ietf.org/id/draft-dreibholz-tsvwg-sctpsocket-multipath-26.txt
MD5: b60cc7f2b112249c1e6677cf4df454b5
Hohendorf, Carsten; Unurkhaan, Esbold and Dreibholz, Thomas: ``Secure SCTP´´ (TXT, 90 KiB, 🇬🇧), Internet Draft draft-hohendorf-secure-sctp-35, IETF, Individual Submission, March 26, 2023, [BibTeX, XML].

Abstract: This document explains the reason for the integration of security functionality into SCTP, and gives a short description of S-SCTP and its services. S-SCTP is fully compatible with SCTP defined in RFC4960, it is designed to integrate cryptographic functions into SCTP.
URL: https://tools.ietf.org/id/draft-hohendorf-secure-sctp-35.txt
MD5: 8c28cac974a073aecb0b10316c0c9d58
Dreibholz, Thomas; Seggelmann, Robin and Becke, Martin: ``Sender Queue Info Option for the SCTP Socket API´´ (TXT, 14 KiB, 🇬🇧), Internet Draft draft-dreibholz-tsvwg-sctpsocket-sqinfo-26, IETF, Individual Submission, March 26, 2023, [BibTeX, XML].

Abstract: This document describes an extension to the SCTP sockets API for querying information about the sender queue.
URL: https://tools.ietf.org/id/draft-dreibholz-tsvwg-sctpsocket-sqinfo-26.txt
MD5: ff3361cc367d2bd53c7a02a4b651c21d
Dreibholz, Thomas and Zhou, Xing: ``Takeover Suggestion Flag for the ENRP Handle Update Message´´ (TXT, 14 KiB, 🇬🇧), Internet Draft draft-dreibholz-rserpool-enrp-takeover-29, IETF, Individual Submission, March 26, 2023, [BibTeX, XML].

Abstract: This document describes the Takeover Suggestion Flag for the ENRP_HANDLE_UPDATE message of the ENRP protocol.
URL: https://tools.ietf.org/id/draft-dreibholz-rserpool-enrp-takeover-29.txt
MD5: 7c542cb2dd330f4f6673d5227ae15df2
Amer, Paul D.; Becke, Martin; Dreibholz, Thomas; Ekiz, Nasif; Iyengar, Janardhan R.; Natarajan, Preethi; Stewart, Randall R. and Tüxen, Michael: ``Load Sharing for the Stream Control Transmission Protocol (SCTP)´´ (TXT, 61 KiB, 🇬🇧), Internet Draft draft-tuexen-tsvwg-sctp-multipath-25, IETF, Individual Submission, February 24, 2023, [BibTeX, XML].

Abstract: The Stream Control Transmission Protocol (SCTP) supports multi-homing for providing network fault tolerance. However, mainly one path is used for data transmission. Only timer-based retransmissions are carried over other paths as well. This document describes how multiple paths can be used simultaneously for transmitting user messages.
URL: https://tools.ietf.org/id/draft-tuexen-tsvwg-sctp-multipath-25.txt
MD5: b5d94e991cccf63ec6eecc0c510f0be6
Dreibholz, Thomas: ``NEAT Sockets API´´ (TXT, 57 KiB, 🇬🇧), Internet Draft draft-dreibholz-taps-neat-socketapi-12, IETF, Individual Submission, February 24, 2023, [BibTeX, XML].

Abstract: This document describes a BSD Sockets-like API on top of the callback-based NEAT User API. This facilitates porting existing applications to use a subset of NEAT's functionality.
URL: https://tools.ietf.org/id/draft-dreibholz-taps-neat-socketapi-12.txt
MD5: 8228b9d263b321b3958d666e6fd52d1a

2022

Mazumdar, Somnath and Dreibholz, Thomas: ``Towards a Privacy Preserving Data Flow Control via Packet Header Marking´´ (PDF, 2009 KiB, 🇬🇧), in Proceedings of the 24th IEEE International Conference on High Performance Computing, Data, and Analytics (HPCC), pp. 1509–1516, DOI 10.1109/HPCC-DSS-SmartCity-DependSys57074.2022.00232, ISBN 979-8-3503-1993-4, Chengdu, Sichuan/People's Republic of China, December 18, 2022, [BibTeX, XML].

Keywords: Cloud, Data, Fog, P4, Packets, Privacy, Routing
Abstract: Computing infrastructure is becoming ubiquitous thanks to the advancement in computing and the network domain. Reliable network communication is essential to offer good quality services, but it is not trivial. There are privacy concerns. Metadata may leak user information even if traffic is encrypted. Some countries have data privacy preserving-related regulations, but end-users cannot control through which path, networks, and hardware their data packets should travel. Even worse, the user cannot declare their privacy preferences. This paper presents an approach to tackle such privacy issues through data privacy-aware routing. The user can specify their preferences for packet routing using marking and filtering. Routing can work according to such specifications. It is implemented by P4, allowing a vendor-independent realisation with standard off-the-shelf hardware and open-source software components. We presented the initial experimental results of a proof-of-concept run on a unified cloud/fog research testbed.
URL: https://www.simula.no/file/hpcc2022pdf/download
MD5: e4736c18f80bee8084c75a587f6c7e0a
Mazumdar, Somnath and Dreibholz, Thomas: ``Towards a Blockchain and Fog-Based Proactive Data Distribution Framework for ICN´´ (PDF, 3018 KiB, 🇬🇧), in Proceedings of the International Conference on Parallel and Distributed Computing, Applications and Technologies (PDCAT), pp. 175–186, DOI 10.1007/978-3-031-29927-8_14, ISBN 978-3-031-29927-8, Sendai, Miyagi/Japan, December 7, 2022, [BibTeX, XML].

Keywords: Blockchain, Data, Distribution, Fog, ICN, Protection
Abstract: Most of today's IP traffic is cloud traffic. Due to a vast, complex and non-transparent Internet infrastructure, securely accessing and delegating data is not a trivial task. Existing technologies of Information-Centric Networking (ICN) make content distribution and access easy while primarily relying on the existing cloud-based security features. The primary aim of ICN is to make data independent of its storage location and application. ICN builds upon traditional distributed computing, which means ICN platforms also can suffer from similar data security issues as distributed computing platforms. We present our ongoing work to develop a secure, proactive data distribution framework. The framework answers the research question, i.e., How to extend online data protection with a secure data distribution model for the ICN platform? Our framework adds a data protection layer over the content distribution network, using blockchain and relying on the fog to distribute the contents with low latency. Our framework is different from the existing works in multiple aspects, such as i) data are primarily distributed from the fog nodes, ii) blockchain is used to protect data and iii) blockchain allows statistical and other information sharing among stakeholders (such as content creators) following access rights. Sharing statistics about content distribution activity can bring transparency and trustworthiness among the stakeholders, including the subscribers, into the ICN platforms. We showed such a framework is possible by presenting initial performance results and our reflections while implementing it on a cloud/fog research testbed.
URL: https://www.simula.no/file/pdcat2022pdf/download
MD5: dcfa615332c774c3f7ae57e1b55eebc2
Mazumdar, Somnath and Dreibholz, Thomas: ``Secure Embedded Living: Towards a Self-contained User Data Preserving Framework´´ (PDF, 336 KiB, 🇬🇧), in IEEE Communications Magazine, vol. 60, pp. 74–80, DOI 10.1109/MCOM.001.2200165, ISSN 0163-6804, November 11, 2022, [BibTeX, XML].

Keywords: IoTs, Cloud, Blockchain, Data, Security, User
Abstract: Smart living represents the hardware-software co-inhabiting with humans for better living standards and improved well-being. Here, hardware monitors human activities (by collecting data) specific to a context. Such data can be processed to offer context-specific valuable insights. Such insights can be used for optimising the well-being, living experience and energy cost of smart homes. This paper proposes a Secure Embedded Living Framework (SELF) that enforces a privacy-preserving data control mechanism by integrating multiple technologies, such as Internet-of-thing, cloud/fog platform, machine learning and blockchain. The primary aim of the SELF is to allow the user to retain more control of its data.
URL: https://www.simula.no/file/commmag2022pdf/download
MD5: aee5a6a9043799f00b9836ce7cafd8d4
Dreibholz, Thomas and Mazumdar, Somnath: ``Find Out: How Do Your Data Packets Travel?´´ (PDF, 7239 KiB, 🇬🇧), in Proceedings of the 18th IEEE International Conference on Network and Service Management (CNSM), pp. 359–363, DOI 10.23919/CNSM55787.2022.9965091, ISBN 978-3-903176-51-5, Thessaloniki, Greece, November 1, 2022, [BibTeX, XML].

Keywords: Internet, Connectivity, Routing, Data, Packets, Traffic Paths
Abstract: In today's communication-centric world, users generate and exchange a massive amount of data. The Internet helps user data to travel from one part of the world to another, via a complex set of network systems. These systems are intelligent, heterogeneous, and non-transparent to users. This paper presents an extensive, trace-driven study of user data traffic covering five years of observations, six large ISPs, 22 different autonomous systems, and a total of 12 countries. This work aims to make users aware of how their data travels in the Internet, as the interests of ISPs majorly influence the data traffic path. Although data traffic should prefer to travel through countries that share land borders, we found that the shortest land distance between the two countries does not impact data path selection.
URL: https://www.simula.no/file/cnsm2022pdf/download
MD5: 1a49b8096e6f7d92d50d2ff98836db4c
Dreibholz, Thomas; Fida, Mah-Rukh; Ahmed, Azza Hassan Mohamed; Ocampo, Andrés Felipe and Michelinakis, Foivos Ioannis: ``A Live Demonstration of In-Band Telemetry in OSM-Orchestrated Core Networks´´ (PDF, 543 KiB, 🇬🇧), in Proceedings of the 47th IEEE Conference on Local Computer Networks (LCN), pp. 245–247, DOI 10.1109/LCN53696.2022.9843413, ISBN 978-1-6654-8001-7, Edmonton, Alberta/Canada, September 28, 2022, [BibTeX, XML].

Keywords: Network Function Virtualisation (NFV), Open Source MANO (OSM), P4, Telemetry, Anomaly Detection
Abstract: Network Function Virtualization is a key enabler to building future mobile networks in a flexible and cost-efficient way. Such a network is expected to manage and maintain itself with least human intervention. With early deployments of the fifth generation of mobile technologies – 5G – around the world, setting up 4G/5G experimental infrastructures is necessary to optimally design Self-Organising Networks (SON). In this demo, we present a custom small-scale 4G/5G testbed. As a step towards self-healing, the testbed integrates four Programming Protocol-independent Packet Processors (P4) virtual switches, that are placed along interfaces between different components of transport and core network. This demo not only shows the administration and monitoring of the Evolved Packet Core (EPC) VNF components, using Open Source MANO, but also as a proof of concept for the potential of P4-based telemetry in detecting anomalous behaviour of the mobile network, such as a congestion in the transport part.
URL: https://www.simula.no/file/lcn2022-telemetry-demo-webpdf/download
MD5: e94078ba8836b84235cf9313a9d69ed1
Michelinakis, Foivos Ioannis; Pujol-Roig, Joan Sebastià; Malacarne, Sara; Xie, Min; Dreibholz, Thomas; Majumdar, Sayantini; Poe, Wint Yi; Patounas, Georgios; Guerrero, Carmen; Elmokashfi, Ahmed Mustafa and Theodorou, Vasileios: ``AI Anomaly Detection for Cloudified Mobile Core Architectures´´ (PDF, 9658 KiB, 🇬🇧), in Transactions on Network and Service Management (TNSM), IEEE Computer Society, DOI 10.1109/TNSM.2022.3203246, ISSN 1932-4537, Los Alamitos, California/U.S.A., August 31, 2022, [BibTeX, XML].

Keywords: Anomaly Detection, Autoencoders, Deep Learning, 5G, AI, Smart Networks, Mobile Networks
Abstract: IT systems monitoring is a crucial process for managing and orchestrating network resources, allowing network providers to rapidly detect and react to most impediment causing network degradation. However, the high growth in size and complexity of current operational networks (2022) demands new solutions to process huge amounts of data (including alarms) reliably and swiftly. Further, as the network becomes progressively more virtualized, the hosting of nfv on cloud environments adds a magnitude of possible bottlenecks outside the control of the service owners. In this paper, we propose two deep learning anomaly detection solutions that leverage service exposure and apply it to automate the detection of service degradation and root cause discovery in a cloudified mobile network that is orchestrated by ETSI OSM. A testbed is built to validate these AI models. The testbed collects monitoring data from the OSM monitoring module, which is then exposed to the external AI anomaly detection modules, tuned to identify the anomalies and the network services causing them. The deep learning solutions are tested using various artificially induced bottlenecks. The AI solutions are shown to correctly detect anomalies and identify the network components involved in the bottlenecks, with certain limitations in a particular type of bottlenecks. A discussion of the right monitoring tools to identify concrete bottlenecks is provided.
URL: https://www.simula.no/file/tnsm2022pdf/download
MD5: 47e525a56f9c1cfd27c249601bdb8c3b
Arouna, Alfred; Bjørnstad, Steinar; Ryan, Stein Jørgen; Dreibholz, Thomas; Rind, Sobia and Elmokashfi, Ahmed Mustafa: ``Network Path Integrity Verification using Deterministic Delay Measurements´´ (PDF, 447 KiB, 🇬🇧), in Proceedings of the 6th IEEE/IFIP Network Traffic Measurement and Analysis Conference (TMA), ISBN 978-3-903176-47-8, Enschede, Overijssel/Netherlands, June 29, 2022, [BibTeX, XML].

Keywords: Network, Deterministic RTT, Alien Switch
Abstract: If an attacker succeeds in planting a device in a network, detecting the alien device can be extremely difficult. With the intuition that every device on the data path contributes to the end-to-end delay, we propose a simple and deterministic measurement-based approach for detecting the insertion of a layer-2 switch on the data path of a network operator. For this purpose, we use commodity hardware and the standard ping tool for collecting ICMP RTTs. To minimise inaccuracies in the measurements, we increase timing determinism on both ICMP source and target by using a real-time kernel on both, a dedicated source (a Linux server) and target (an RPI4 with custom image). Additionally, we manipulate real-time attributes for prioritising the ping process. By using this approach on different loaded networks: lab, campus network, research and education network and an ISP, we are able to reliably detect that a switch was added at the end of the path or within it. Our method yields an excellent performance on networks with considerable cross traffic as well as lightly loaded networks.
URL: https://www.simula.no/file/tmacamerareadynetworkpathintegrityverificationusingdeterministicdelaymeasurementspdf/download
MD5: 2e26d7e6bb08e8d8fd9fe6da67b960c1
Dreibholz, Thomas; Ahmed, Azza Hassan Mohamed; Fida, Mah-Rukh; Ocampo, Andrés Felipe and Michelinakis, Foivos Ioannis: ``Detecting Issues with In-Band Telemetry in OSM-Orchestrated Core Networks´´ (PDF, 4769 KiB, 🇬🇧), Presentation at the OSM#13 Ecosystem Day, Demo presentation, Virtual, June 15, 2022, [BibTeX, XML].

Keywords: Network Function Virtualisation (NFV), Open Source MANO (OSM), P4, Telemetry, Anomaly Detection
Abstract: Open Source MANO is a helpful tool to manage and orchestrate the instantiation of core network setups, like Network Service (NS) instances of our SimulaMet OpenAirInterface Virtual Network Function (VNF) for Enhanced Packet Cores (EPC). We furthermore extended our NS with VNF instances of Programming Protocol-independent Packet Processors (P4) switches, in order to allow for in-band telemetry. With in-band telemetry, it is possible to flexibly add, process, and remove telemetry information to traffic within the packet core, in order to allow for fine-granular evaluation of the system performance and the users' experienced quality of service. In our presentation and demo, we would like to provide an overview of our ongoing work on P4-based in-band telemetry in an OSM-orchestrated 4G core, which is used for detecting performance problems and anomalies in the network based on machine learning. We would furthermore like to demonstrate the details of our setup to the audience in a live demo.
URL: https://www.simula.no/file/osmhackfest13-presentationpdf/download
MD5: 8e45be5e236c300b6172de1948edcd61
Dreibholz, Thomas and Mazumdar, Somnath: ``Load Distribution for Mobile Edge Computing with Reliable Server Pooling´´ (PDF, 3664 KiB, 🇬🇧), in Proceedings of the 4th International Workshop on Recent Advances for Multi-Clouds and Mobile Edge Computing (M2EC) in conjunction with the 36th International Conference on Advanced Information Networking and Applications (AINA), pp. 590–601, DOI 10.1007/978-3-030-99619-2_55, ISBN 978-3-030-99619-2, Sydney, New South Wales/Australia, April 15, 2022, [BibTeX, XML].

Keywords: Mobile Edge Computing (MEC), Multi-Cloud Computing, Reliable Server Pooling (RSerPool), Load Distribution, Cloud Computing, Serverless Computing
Abstract: The energy-efficient computing model is a popular choice for both, high-performance and throughput-oriented computing ecosystems. Mobile (computing) devices are becoming increasingly ubiquitous to our computing domain, but with limited resources (true both for computation as well as for energy). Hence, workload offloading from resource-constrained mobile devices to the edge and maybe later to the cloud become necessary as well as useful. Thanks to the persistent technical breakthroughs in global wireless standards (or in mobile networks), together with the almost limitless amount of resources in public cloud platforms, workload offloading is possible and cheaper. In such scenarios, Mobile Edge Computing (MEC) resources could be provisioned in proximity to the users for supporting latency-sensitive applications. Here, two relevant problems could be: i) How to distribute workload to the resource pools of MEC as well as public (multi-)clouds? ii) How to manage such resource pools effectively? To answer these problems in this paper, we examine the performance of our proposed approach using the Reliable Server Pooling (RSerPool) framework in more detail. We also have outlined the resource pool management policies to effectively use RSerPool for workload offloading from mobile devices into the cloud/MEC ecosystem.
URL: https://www.simula.no/file/m2ec2022pdf/download
MD5: 9781c73c07685768b70b5cd7250b8b24
Elmokashfi, Ahmed Mustafa; Kvalbein, Amund; Al-Selwi, Anas Saeed; Michelinakis, Foivos Ioannis and Dreibholz, Thomas: ``Norske mobilnett i 2021 – Tilstandsrapport fra Centre for Resilient Networks and Applications´´ (PDF, 10513 KiB, 🇳🇴), Simula Metropolitan Center for Digital Engineering, Centre for Resilient Networks and Applications (CRNA), ISBN 82-92593-36-5, Oslo/Norway, April 6, 2022, [BibTeX, XML].

Abstract: Denne rapporten er utarbeidet av Center for Resilient Networks and Applications (CRNA), som er en del av Simula Metropolitan Center for Digital Engineering. CRNA driver grunn- leggende forskning innen robusthet og sikker- het i nettverk med mandat og finansiering fra Kommunal- og moderniseringsdepartementet. Senteret produserer en årlig rapport om tilstan- den i norske mobilnett. Årets rapport er den niende i rekken.
URL: https://www.simula.no/sites/default/files/norske_mobilnett_i_2021.pdf
MD5: 0d3cc03901b210a639bc62c872997434
Dreibholz, Thomas: ``NorNet – A Linux- and Open-Source-Software-based International Platform for Networking Research´´ (PDF, 7977 KiB, 🇬🇧), in Proceedings of the Linux Conference Australia (LCA), Virtual, January 15, 2022, [BibTeX, XML].

Keywords: NorNet, Testbed, Multi-Homing, Multi-Path Transport, Linux, Open Source
Abstract: The NorNet testbed is an Internet testbed platform for research on multi-homed systems. The particular property of multi-homed systems is to be connected to multiple Internet Service Providers (ISP) simultaneously. Its initial purpose is of course to still provide connectivity in case of ISP/network failures. But does it really work that well, also with current protocols and applications? And redundancy does not come for free. A user connected to multiple ISPs will also receive multiple Internet bills each month. So, is there a possibility to make further use of multi-homing in the usual case where nothing goes wrong? Obviously, there are a lot of interesting research questions, which need to be examined in realistic Internet setups! Therefore, we are building up the NorNet open Internet testbed platform as a Linux- and Open-Source-software-based infrastructure, which currently spreads over multiple sites in different countries. NorNet makes extensive use of advanced Linux features like Kernel-based Virtualisation (KVM), Linux Containers (LXC), BTRFS file system features, IP routing rules, Stream Control Transmission Protocol (SCTP), Multi-Path TCP (MPTCP), and many more. The goal of this talk is therefore to present an overview of the testbed, its underlying Linux features, and how they are combined to provide the multi-homing features to the various testbed users. This particularly includes an overview of how to make use of multi-path transport with MPTCP – based on the Linux MPTCP implementation – in multi-homed environments. The idea is to provide guidelines for also utilising multi-homing features in own projects.
URL: https://www.simula.no/file/lca2022-presentationpdf/download
MD5: 65d811842205bd1f11a8518d1c3455e4

2021

Dreibholz, Thomas; Ocampo, Andrés Felipe and Fida, Mah-Rukh: ``Demonstration of P4-Based In-Band Telemetry for OSM-Orchestrated 4G/5G Testbeds´´ (PDF, 5252 KiB, 🇬🇧), Presentation at the OSM#12 Ecosystem Day, Demo presentation, Virtual, December 1, 2021, [BibTeX, XML].

Keywords: Network Function Virtualisation, In-Band Telemetry, P4, Open Source MANO, OpenAirInterface, 5G
Abstract: The SimulaMet OpenAirInterface VNF provides an OpenAirInterface-based Enhanced Packet Core (EPC), with separate VDUs for HSS, MME, SPGW-C and SPGW-U. To allow for advanced in-band telemetry, we have extended this VNF to add switches with Programming Protocol-independent Packet Processors (P4) to all relevant virtual links inside the EPC. P4 allows full programability of the packet forwarding behaviour, and especially allows to extend packets with additional information for in-band telemetry. This information can be read by other P4 instances to allow for fine-granular performance data collection. In this presentation and live demonstration, we would like show the solutions chosen to efficiently use OSM for handling our extended EPC, and in particular we would like to highlight the possibilities to perform P4-based in-band telemetry to evaluate the performance of the mobile network. Finally, we would also like to show the audience a live demo of our testbed setup with telemetry collection.
URL: https://www.simula.no/file/osmhackfest12-presentationpdf/download
MD5: a8a7bb46192c0b1179f98ad255df5caf
Dreibholz, Thomas and Mazumdar, Somnath: ``A Demo of Workload Offloading in Mobile Edge Computing Using the Reliable Server Pooling Framework´´ (PDF, 1888 KiB, 🇬🇧), in Proceedings of the 46th IEEE Conference on Local Computer Networks (LCN), Demo presentation, Edmonton, Alberta/Canada, October 7, 2021, [BibTeX, XML].

Keywords: Mobile Edge Computing (MEC), Multi-Cloud Computing, Reliable Server Pooling (RSerPool), Network Function Virtualisation (NFV), Evolved Packet Core (EPC), Demonstration
Abstract: Mobile Edge Computing (MEC) places cloud resources nearby the user, to provide support for latency-sensitive applications. Offloading workload from resource-constrained mobile devices (such as smartphones) into the cloud ecosystem is becoming increasingly popular. In this demonstration, we show how to deploy a mobile network (with OpenAirInterface and Open Source MANO), as well as to adapt the Reliable Server Pooling (RSerPool) framework to efficiently manage MEC as well as multi-cloud resources to run an interactive demo application.
URL: https://www.simula.no/file/lcn2021-rserpool-webpdf/download
MD5: ebb3fd109d337e41823f72be8483cdd1
Chen, Min; Raza, Muhammad Waleed; Dreibholz, Thomas; Zhou, Xing and Tan, Yuyin: ``A Multi-Parameter Comprehensive Optimized Algorithm for MPTCP Networks´´ (PDF, 3320 KiB, 🇬🇧), in Electronics, vol. 10, no. 16, pp. 1–19, MDPI, DOI 10.3390/electronics10161942, ISSN 2079-9292, Basel/Switzerland, August 12, 2021, [BibTeX, XML].

Abstract: With the increasing deployment of the Multi-Path Transmission Control Protocol (MPTCP) in heterogeneous network setups, there is a need to understand how its performance is affected in practice both by traditional factors such as round-trip time measurements, buffer predictive modelling and by calculating the impact factors of network subflows. Studies have shown that path management and packet scheduling have a large effect on overall performance and required limited resources with different congestion control parameters. Unfortunately, most of the previous studies have focused almost exclusively on the improvement of a single parameter, without a holistic view. To deal with this issue effectively, this paper puts forward a Multi-Parameter Comprehensive Optimized Algorithm (MPCOA), which can find the smaller buffer size and select the appropriate congestion control and path management algorithm on the premise of ensuring larger throughput. Experiments of three scenarios show that MPCOA can save the buffer space and subflow resources, and achieve high throughput. Meanwhile, a set of quantitative improvement results given by MPCOA is convenient for us to evaluate the quality of MPTCP network, and provide reference for our ongoing future work, like for 4G/5G, Internet of Things and Star Link networks.
URL: https://www.mdpi.com/2079-9292/10/16/1942/pdf
MD5: 81a1562c9bf7bc0a29877932ed6c9cdb
Xie, Min; Dreibholz, Thomas; Michelinakis, Foivos Ioannis; Pujol-Roig, Joan; Poe, Wint Yi; Elmokashfi, Ahmed Mustafa; Majumdar, Sayantini and Malacarne, Sara: ``An Exposed Closed-Loop Model for Customer-Driven Service Assurance Automation´´ (PDF, 1131 KiB, 🇬🇧), in Proceedings of the 30th IEEE European Conference on Networks and Communications (EuCNC), pp. 419–424, DOI 10.1109/EuCNC/6GSummit51104.2021.9482533, ISBN 978-1-6654-1526-2, Porto/Portugal, June 9, 2021, [BibTeX, XML].

Keywords: Autonomous Management, Closed Loop, Machine Learning, Service Exposure, Monitoring
Abstract: Artificial Intelligence (AI) is widely applied in telecommunications to enable zero-touch automation in network operation and service management. Due to the high complexity, deploying advanced AI mechanisms is not always feasible inside the operator’s network domains. Instead, via service exposures, it becomes possible for vertical customers to integrate their external AI solutions with the network and service management system to form a closed loop (CL) and contribute to the automation process. In this paper, we propose an exposed CL model based on service exposure and apply it to automate service assurance tasks like autoscaling in a network function virtualization (NFV) system orchestrated by ETSI Open Source MANO (OSM). A testbed is built to validate the model. It collects monitoring data from the OSM monitoring module and external monitoring tools. Vertical customers drive and customize their AI solutions to aggregate these data sets and run analytics to detect and predict anomalies prepared for scaling. Preliminary analysis demonstrates the added values of customer-driven monitoring and analysis via the exposed CL.
URL: https://www.simula.no/file/eucnc2021pdf/download
MD5: efae267f1c2144b7639a39724b35aa62
Dreibholz, Thomas and Mazumdar, Somnath: ``Reliable Server Pooling Based Workload Offloading with Mobile Edge Computing: A Proof-of-Concept´´ (PDF, 1113 KiB, 🇬🇧), in Proceedings of the 3rd International Workshop on Recent Advances for Multi-Clouds and Mobile Edge Computing (M2EC) in conjunction with the 35th International Conference on Advanced Information Networking and Applications (AINA), vol. 3, pp. 582–593, DOI 10.1007/978-3-030-75078-7_58, ISBN 978-3-030-75078-7, Toronto, Ontario/Canada, May 14, 2021, [BibTeX, XML].

Keywords: Mobile Edge Computing (MEC), Multi-Cloud Computing, Reliable Server Pooling (RSerPool), Network Function Virtualisation (NFV), Evolved Packet Core (EPC), 5G
Abstract: In recent times, mobile broadband devices have become almost ubiquitous. However, battery-powered devices (such as smartphones), have limitations on energy consumption, computation power and storage space. Cloud computing and Mobile Edge Computing (MEC) can provide low-latency compute and storage services at the vicinity of the user, MEC in particular due to the upcoming 5G networks. However, the complexity lies in how to simply and efficiently realise MEC services, with the auxiliary public (multi-)cloud resources? In this paper, we propose a proof-of-concept for using Reliable Server Pooling (RSerPool) as a light-weight layer of managing resource pools and handling application sessions with these pools. Our approach is simple, efficient, has low overhead and is available as open source. Here, we demonstrate the usefulness of our approach by measuring in a test setup, with a 4G testbed connected to MEC and public multi-cloud resources.
URL: https://www.simula.no/file/m2ec2021-webpdf/download
MD5: a75fca110072cf3941409864791e0986
Abdulkadir, Mohammed A.; Alay, Özgü; Alexiou, Angeliki; Anastasopoulos, Markos; Antevski, Kiril; Aumayr, Erik; Ayed, Dhouha; Baranda, Jordi; Behravesh, Rasoul; Benzaid, Chafika; Bisson, Pascal; Bosneag, Anne-Marie Cristina; Boulogeorgos, Alexandros-Apostolos A.; Calero, José Alcaraz; Carrozzo, Gino; Casetti, Claudio Ettore; Caso, Giuseppe; Celdrán, Alberto Huertas; Chergui, Hatim; Chiasserini, Carla Fabiana; Chinchilla-Romero, Lorena; Chollon, Geoffroy; Cogalan, Tezcan; Colman-Meixner, Carlos; Conti, Andrea; Cosmas, John; Costa-Requena, José; Desai, Rachana; Devoti, Francesco; Diamanti, Maria; Dreibholz, Thomas; Elmokashfi, Ahmed Mustafa; Feghhi, Saman; Garcia-Saavedra, Andres; Gavras, Anastasius; Ghoraishi, Mir; Giannopoulos, Anastasios; Goodarzi, Meysam; Gramaglia, Marco; Guimarães, Carlos; Gürkan, Gür; He, Jiguang; Hrasnica, Halid; Jimeno, Elisa; Kakkavas, Grigorios; Kaloxylos, Alexandros; Karyotis, Vasileios; Katta, Saimanoj; Katzouris, Nikos; Kennouche, Takai Eddine; Klinkenberg, Ralf; Kokkoniemi, Joonas; Kondepu, Koteswararao; Lazarakis, Fotis; Lekidis, Alexios; Li, Xi; Lopez, Diego; Magoula, Lina; Mahmood, Kashif; Majumdar, Sayantini; Malinverno, Marco; Mangues-Bafalluy, Josep; Martínez, Ricardo; Martín-Pérez, Jorge; Martrat, Josep; Meunier, Ben; Mohamed, Ramy; Morselli, Flavio; Muñoz, Juan José Ramos; Muñoz-Luengo, Pablo; Muri, Daniel Camps; Murphy, Chris; Oca, Edgardo Montes De; Papagianni, Chrysa; Papavassiliou, Symeon; Perales, Antonio Agustín Pastor; Pérez, Gregorio Martínez; Pérez, Manuel Gil; Poe, Wint Yi; Prados-Garzon, Jonathan; Renzo, Marco Di; Roig, Joan Pujol; Sánchez, Pedro Miguel; Schepper, Koen De; Shi, Lina; Skarmeta, Antonio; Spantideas, Sotirios; Srinivasan, Gokul Krishna; Stamou, Adamantia; Subramanya, Tejas; Trakadas, Panagiotis; Tzanakaki, Anna; Valcarenghi, Luca; Valero, José María Jorquera; Videv, Stefan; Wang, Qi; Wang, Yue; Xie, Min; Xu, Zhao; Yan, Shuangyi; Yaqub, Edwin; Yesilkaya, Anil; Zanzi, Lanfranco; Zemouri, Sofiane; Zeydan, Engin; Zhang, Xun and Zhou, Xueqing: ``AI and ML –- Enablers for Beyond 5G Networks´´ (PDF, 5745 KiB, 🇬🇧), 5G PPP Technology Board, DOI 10.5281/zenodo.429989, May 11, 2021, [BibTeX, XML].

Abstract: This white paper on AI and ML as enablers of beyond 5G (B5G) networks is based on contributions from almost 20 5G PPP projects, coordinated through the 5G PPP Technology Board, that research, implement and validate 5G and B5G network systems. The paper introduces the main relevant mechanisms in Artificial Intelligence (AI) and Machine Learning (ML), currently investigated and exploited for enhancing 5G and B5G networks.
URL: https://5g-ppp.eu/wp-content/uploads/2021/05/AI-MLforNetworks-v1-0.pdf
MD5: eff564f5526d8a64b0e6d824557536a8
Dreibholz, Thomas: ``NorNet at Hainan University in 2021: Getting Started with NorNet Core – A Remote Tutorial´´ (PDF, 4654 KiB, 🇬🇧), Tutorial at Hainan University, College of Information Science and Technology (CIST), Haikou, Hainan/People's Republic of China, January 15, 2021, [BibTeX, XML].

Keywords: NorNet, NorNet Core, Testbed, Multi-Homing, Multi-Path Transport, Tutorial
Abstract: This tutorial – presented for students at the College of Information Science and Technology (CIST) at Hainan University – provides an introduction on how to get access to the NorNet Core testbed as well as how to run experiments in the testbed in 2021.
URL: https://www.simula.no/file/haikou2021-nornet-tutorialpdf/download
MD5: 7c7a0d08c3b357c0d3086e95d033c63e
Elmokashfi, Ahmed Mustafa; Arouna, Alfred; Livadariu, Ioana Alexandrina; Fida, Mah-Rukh; Kvalbein, Amund; Al-Selwi, Anas Saeed; Dreibholz, Thomas and Bryhni, Haakon: ``A Multi-Perspective Study of Internet Performance during the COVID-19 Outbreak´´ (PDF, 1813 KiB, 🇬🇧), Arxiv, January 13, 2021, [BibTeX, XML].

Abstract: The rapid spread of the novel corona virus, SARS-CoV-2, has prompted an unprecedented response from governments across the world. A third of the world population have been placed in varying degrees of lockdown, and the Internet has become the primary medium for conducting most businesses and schooling activities. This paper aims to provide a multi-prospective account of Internet performance during the lockdown. We investigate the performance of the Internet control plane and data plane from a number of globally spread vantage points. We also look closer at two case studies. First, we look at growth in video traffic during the pandemic, using traffic logs from a global video conferencing provider. Second, we leverage a country-wide deployment of measurement probes to assess the performance of mobile networks during the outbreak. We find that the lockdown has visibly impacted almost all aspects of Internet performance. Access networks have experienced an increase in peak and off-peak end to end latency. Mobile networks exhibit significant changes in download speed, while certain types of video traffic has increased by an order of magnitude.
URL: https://arxiv.org/pdf/2101.05030.pdf
MD5: ac685610f5bd32077391c0a5be43f046
Dreibholz, Thomas: ``NorNet at Hainan University in 2021: From Simulations to Real-World Internet Measurements for Multi-Path Transport Research – A Remote Presentation´´ (PDF, 14184 KiB, 🇬🇧), Keynote Talk at Hainan University, College of Information Science and Technology (CIST), Haikou, Hainan/People's Republic of China, January 8, 2021, [BibTeX, XML].

Keywords: NorNet, NorNet Core, NorNet Edge, Testbed, Multi-Homing, Introduction, Status
Abstract: A large fraction of the communication in the Internet is handled by the Transmission Control Protocol (TCP). Since the first deployments of this protocol more than 30 years ago, the spectrum of applications as well as the structure of the network have developed at a fast pace. For example, today's network devices, like smartphones and laptops – i.e. particularly many devices in the area of mobile computing – frequently have an interesting property: the existence of multiple IP addresses (IPv4 and/or IPv6). The addresses may even change due to mobility. This property, denoted as multi-homing, can be utilised for multi-path transport, i.e. the simultaneous usage of multiple paths in the network to improve performance. Multi-path transport is a hot topic in the Internet Engineering Task Force (IETF), which is the standardisation organisation for the Internet. This talk provides an overview of the work in the areas of multi-homing and multi-path transport, with focus on the area of the protocols TCP and Stream Control Transmission Protocol (SCTP) with their experimental extensions Multi-Path TCP (MPTCP) and Concurrent Multi-Path Transfer for SCTP (CMT-SCTP). It particularly shows the sequence of research and selected results, beginning from a simple simulation model, via lab setups and small Internet scenarios, up to the large-scale, international testbed project NorNet. NorNet, and particularly its landline network part NorNet Core, is furthermore described in some detail. Based on NorNet, it is finally possible to validate simulation results in real-world, multi-homed networks, in order to provide valuable input to the ongoing IETF standardisation processes of MPTCP and CMT-SCTP. Particularly, it will also show how the NorNet testbed can be utilised for research at Hainan University in 2021.
URL: https://www.simula.no/file/haikou2021-multipath-presentationpdf/download
MD5: 37f2850a007882bb0c12c29b0780e067

2020

Dreibholz, Thomas: ``Custom-Made Enhanced Packet Cores as Network Services for 4G/5G Testbeds managed with Open Source MANO´´ (PDF, 4221 KiB, 🇬🇧), Presentation at the Mosaic5G Workshop, December 3, 2020, [BibTeX, XML].

Keywords: Network Function Virtualisation, Evolved Packet Core, Open Source MANO, OpenAirInterface, 5G
Abstract: Setting up Enhanced Packet Cores (EPC) – like the Mosaic5G OpenAirInterface-based EPC – for 4G/5G Testbeds is a complicated and error-prone task. Therefore, we developed the SimulaMet OpenAirInterface VNF, a complex 4-VDU VNF, which upon instantiation builds the components of the EPC from scratch from given source Git repositories. That is, based on the parametrisation, users can easily create tailor-made EPCs for their projects, particularly EPCs based on the Mosaic5G FlexRAN sources. In this presentation, we would like to shortly highlight the solutions chosen to efficiently use OSM for handling the instantiation process, performing telemetry, and debugging issues. That is, we particularly would like to present to the Mosaic5G audience some lessons learned during the ongoing development.
URL: https://www.simula.no/file/m5g-2020-presentationpdf/download
MD5: a0cddc5183325e6585df53943d0592df
Dreibholz, Thomas and Ocampo, Andrés Felipe: ``Managing Tailor-Made Enhanced Packet Cores for 4G/5G Testbeds in OSM with the SimulaMet OpenAirInterface VNF´´ (PDF, 7354 KiB, 🇬🇧), Presentation at the OSM Hackfest, December 2, 2020, [BibTeX, XML].

Keywords: Network Function Virtualisation, Evolved Packet Core, Open Source MANO, OpenAirInterface, 5G
Abstract: The SimulaMet OpenAirInterface VNF is a complex 4-VDU VNF, allowing its users to instantiate and maintain a tailor-made Enhanced Packet Core (EPC) for 4G/5G mobile broadband testbeds. The EPC components are directly built from their sources during instantiation, allowing to use customised versions according to the users' needs. A general overview has already been presented during the OSM Hackfest in March 2020. In this presentation and live demonstration, we would like to highlight the solutions chosen to efficiently use OSM for handling the instantiation process, provide telemetry, and to debug issues. That is, we particularly would like to present to the audience the lessons learned during the ongoing development. Finally, we would also like to show the audience a live demo of an OSM-managed 4G testbed setup with telemetry collection.
URL: https://www.simula.no/file/osmhackfest10-presentationpdf/download
MD5: 9a49992810016c554185721a8f70f12f
Dreibholz, Thomas; Saxena, Paresh and Skinnemoen, Harald: ``Efficient Network Coding for Satellite Applications: A Live Demo of HENCSAT and NECTOR´´ (PDF, 2004 KiB, 🇬🇧), in Proceedings of the 45th IEEE Conference on Local Computer Networks (LCN), Demo presentation, Sydney, New South Wales/Australia, November 18, 2020, [BibTeX, XML].

Keywords: Unmanned Aerial Vehicles, Satellite Communications, Network Coding, HENCSAT, NECTOR, Live Demo
Abstract: Satellite communication is available anywhere on earth, allowing connectivity to systems like Unmanned Aerial Vehicles (UAV) in very remote geographical areas. However, satellite airtime is expensive, and a reduction of the amount of transmitted data can lead to significant cost savings. The goal of the Highly-Efficient Network Coding for Satellite Applications (HENCSAT) project is to reduce such costs by using our approach Network Coding with Torrents (NECTOR). NECTOR combines network coding, Torrent-based transmission, and H.265 highly efficient video encoding. In our demonstration, we would like to showcase NECTOR in an interactive HENCSAT test bench setup.
URL: https://www.simula.no/file/lcn2020-hencsat-demo-webpdf/download
MD5: bd6a2b2ee60c0057091e35fdb3d1c683
Ocampo, Andrés Felipe; Dreibholz, Thomas; Fida, Mah-Rukh; Elmokashfi, Ahmed Mustafa and Bryhni, Haakon: ``Integrating Cloud-RAN with Packet Core as VNF Using Open Source MANO and OpenAirInterface´´ (PDF, 430 KiB, 🇬🇧), in Proceedings of the 45th IEEE Conference on Local Computer Networks (LCN), Demo presentation, Sydney, New South Wales/Australia, November 18, 2020, [BibTeX, XML].

Keywords: Cloud Radio Access Network (Cloud-RAN), Ethernet Xhaul, Functional Splits, Network Function Virtualisation (NFV), Open Source MANO (OSM), Fronthaul
Abstract: The Cloud-based Radio Access Network (Cloud-RAN) architecture and Network Function Virtualization (NFV) are key enablers to building future mobile networks in a flexible and cost-efficient way. With early deployments of the fifth generation of mobile technologies - 5G - around the world, setting up 4G/5G experimental infrastructures is necessary to optimally design 5G networks. In this demo, we present a custom small-scale 4G/5G testbed based on OpenAirInterface and Open Source MANO. The testbed integrates a Cloud-RAN based on switched Ethernet Xhaul and functional splitting, with an Evolved Packet Core (EPC) deployed as a Virtual Network Function (VNF) in a cloud infrastructure. Using Open Source MANO, this demo shows the administration and monitoring of the EPC VNF components. Moreover, as proof of concept, collection and visualization of telemetry will be shown for two smart-phones connected to the network through the Cloud-RAN.
URL: https://www.simula.no/file/lcn2020-simulametepc-demo-webpdf/download
MD5: 0c6e5c6588aedf71fe9af3a9997a9d99
Chen, Min; Dreibholz, Thomas; Zhou, Xing and Yang, Xuelei: ``Improvement and Implementation of a Multi-Path Management Algorithm Based on MPTCP´´ (PDF, 526 KiB, 🇬🇧), in Proceedings of the 45th IEEE Conference on Local Computer Networks (LCN), pp. 134–143, DOI 10.1109/LCN48667.2020.9314778, ISBN 978-1-7281-7158-6, Sydney, New South Wales/Australia, November 16, 2020, [BibTeX, XML].

Keywords: MPTCP, Multi-path Management, PCDC, Subflow Impact Factor, Data Stream Classification
Abstract: The core idea of Multi-Path Transmission Control Protocol (MPTCP) is to share network resources by distributing payload data transmission among multiple subflows. Then, multiple paths in the underlying network can be used to maximize the overall connection throughput. However, the concurrent transmission of not all subflows aggregation can improve network performance, because of the performance difference of each subflow. In this paper, we propose a new FullMesh algorithm based on Path Characteristic and Data Characteristic (PCDC), in which the Subflow Impact Factor (IF) is used as a subflow characteristic to predict the impact of the subflow on the overall throughput. Then, different path sets are adopted for different sizes of traffic. The PCDC algorithm is evaluated in the NorNet Core testbed, compared with the FullMesh algorithm. Our research results show that the PCDC algorithm can improve the network throughput, and reduce the overall completion time of small data streams.
URL: https://www.simula.no/file/lcn2020-pathmgt-webpdf/download
MD5: d6ac16601873ae7788bddd205d65e70d
Dreibholz, Thomas: ``A 4G/5G Packet Core as VNF with Open Source MANO and OpenAirInterface´´ (PDF, 811 KiB, 🇬🇧), in Proceedings of the 28th IEEE International Conference on Software, Telecommunications and Computer Networks (SoftCOM), pp. 1–3, DOI 10.23919/SoftCOM50211.2020.9238222, ISBN 978-953-290-099-6, Hvar, Dalmacija/Croatia, September 19, 2020, [BibTeX, XML].

Keywords: Network Function Virtualisation (NFV), Virtual Network Function (VNF), Evolved Packet Core (EPC), OpenAirInterface, Open Source MANO (OSM), Testbed
Abstract: 5G, the fifth generation of mobile broadband networks, is going to make a large range of new applications possible. However, further research is necessary, and the basic step, i.e. setting up a 4G/5G testbed infrastructure, is a complicated and error-prone task. In this abstract and poster, we introduce our open source SimulaMet EPC Virtual Network Function (VNF), as an easy way to set up a 4G/5G testbed based on Open Source MANO and OpenAirInterface. We would like to showcase how a researcher can use our VNF as part of his own research testbed setup. Therefore, the focus is particularly on the user interface details and features of the SimulaMet EPC VNF.
URL: https://www.simula.no/file/softcom2020-simulametepc-webpdf/download
MD5: e5573d55de90860f8dababa28911e819
Dreibholz, Thomas: ``HiPerConTracer - A Versatile Tool for IP Connectivity Tracing in Multi-Path Setups´´ (PDF, 4898 KiB, 🇬🇧), in Proceedings of the 28th IEEE International Conference on Software, Telecommunications and Computer Networks (SoftCOM), pp. 1–6, DOI 10.23919/SoftCOM50211.2020.9238278, ISBN 978-953-290-099-6, Hvar, Dalmacija/Croatia, September 17, 2020, [BibTeX, XML].

Keywords: HiPerConTracer, Traceroute, Ping, Multi-Path Transport, NorNet, NorNet Core
Abstract: Nowadays, we see a steadily increasing number of Internet devices with connections to multiple networks. For example, every smartphone provides mobile broadband and Wi-Fi connectivity. Multi-path transport protocols, like MPTCP, CMT-SCTP or Multipath-QUIC, allow for utilising all connected networks simultaneously. However, while there is a lot of research on the Transport Layer aspects of multi-path transport, there is not much work on the Network Layer perspective, yet. In this paper, we introduce our Open Source tool HiPerConTracer (High-Performance Connectivity Tracer) for efficient, parallelised, long-term measurements of the path connectivity characteristics among multi-homed Internet systems. HiPerConTracer is now running as a permanent feature in the NorNet Core infrastructure, which is used for research on multi-homed systems, and in particular for research on multi-path transport. Based on the HiPerConTracer data collected in NorNet Core so far, we finally present some interesting results from the analysis of the inter-continental site connectivity between China and Norway in January 2020.
URL: https://www.simula.no/file/softcom2020-hipercontracer-webpdf-0/download
MD5: 676791cf458caa2e9f21688227fc6219
Livadariu, Ioana Alexandrina; Dreibholz, Thomas; Al-Selwi, Anas Saeed; Bryhni, Haakon; Lysne, Olav; Bjørnstad, Steinar and Elmokashfi, Ahmed Mustafa: ``On the Accuracy of Country-Level IP Geolocation´´ (PDF, 421 KiB, 🇬🇧), in Proceedings of the ACM/IRTF Applied Networking Research Workshop (ARNW), pp. 67–73, DOI 10.1145/3404868.3406664, ISBN 978-1-4503-8039-3, Madrid/Spain, July 27, 2020, [BibTeX, XML].

Abstract: The proliferation of online services comprised of globally spread microservices has security and performance implications. Understanding the underlying physical paths connecting end points has become important. This paper investigates the accuracy of commonly used IP geolocation approaches in geolocating end-to-end IP paths. To this end, we perform a controlled measurement study to collect IP level paths. We find that existing databases tend to geolocate IPs that belong to networks with global presence and those move between networks erroneously. A small percentage of IP geolocation disagreement between databases results in a significant disagreement when geolocating end-to-end paths. Geolocating one week of RIPE traceroute data validates our observations.
URL: https://www.simula.no/file/anrw2020pdf/download
MD5: 2d789a1f7bf2ef99da8b595b2a1bb546
Saxena, Paresh; Dreibholz, Thomas; Skinnemoen, Harald; Alay, Özgü; Vazquez-Castro, Ángeles; Ferlin, Simone and Acar, Guray: ``Resilient Hybrid SatCom and Terrestrial Networking for Unmanned Aerial Vehicles´´ (PDF, 1059 KiB, 🇬🇧), in Proceedings of the 39th IEEE International Conference on Computer Communications (INFOCOM), International Workshop on Wireless Sensor, Robot and UAV Networks (WiSARN), pp. 418–423, DOI 10.1109/INFOCOMWKSHPS50562.2020.9162943, ISBN 978-1-7281-8696-2, Toronto, Ontario/Canada, July 6, 2020, [BibTeX, XML].

Abstract: Today, Unmanned Aerial Vehicles (UAVs) are widely used in many different scenarios including search, monitoring, inspection, and surveillance. To be able to transmit the sensor data from the UAVs to the destination reliably within tangible response times to the relevant content is crucial, especially for tactical use cases. In this paper, we propose network coded torrents (NECTOR) to leverage multiple network interfaces for resilient hybrid satellite communications (SatCom) and terrestrial networking for UAVs. NECTOR is significantly different from the state-of-the-art multipath protocols such as multipath TCP (MPTCP) as it does not require any additional packet scheduler, rate-adaptation or forward error correction. We present the design and implementation of NECTOR, and evaluate its performance compared to MPTCP. Our experimental results show that NECTOR provides goodput (up to 70\%) higher than MPTCP with 5.49 times less signaling overhead.
URL: https://www.simula.no/file/infocom2020pdf/download
MD5: 6b7cadc81a5a88b954f22389db33499b
Elmokashfi, Ahmed Mustafa; Kvalbein, Amund; Christiansson, Mikael; Al-Selwi, Anas Saeed; Dreibholz, Thomas and Mıdoğlu, Çise: ``Norske mobilnett i 2019 – Tilstandsrapport fra Centre for Resilient Networks and Applications´´ (PDF, 18663 KiB, 🇳🇴), Simula Metropolitan Center for Digital Engineering, Centre for Resilient Networks and Applications (CRNA), ISBN 978-82-92593-28-8, Oslo/Norway, June 30, 2020, [BibTeX, XML].

Abstract: Denne rapporten er utarbeidet av Center for Resilient Networks and Applications (CRNA), som er en del av Simula Metropolitan Center for Digital Engineering. CRNA driver grunn- leggende forskning innen robusthet og sikkerhet i nettverk med mandat og finansiering fra Kommunal- og moderniseringsdepartementet. Senteret produserer en årlig rapport om tilstanden i norske mobilnett. Årets rapport er den sjuende i rekken.
URL: https://www.simula.no/sites/default/files/norske_mobilnett_i_2019_1.pdf
MD5: 74325fa42c888b169941ffa0ae193227
Xie, Min; Pujol-Roig, Joan Sebastià; Michelinakis, Foivos Ioannis; Dreibholz, Thomas; Guerrero, Carmen; Sánchez, Adrián Gallego; Poe, Wint Yi; Wang, Yue and Elmokashfi, Ahmed Mustafa: ``AI-Driven Closed-Loop Service Assurance with Service Exposures´´ (PDF, 713 KiB, 🇬🇧), in Proceedings of the 29th IEEE European Conference on Networks and Communications (EuCNC), pp. 265–270, DOI 10.1109/EuCNC48522.2020.9200943, ISBN 978-1-7281-4355-2, Dubrovnik, Dubrovnik-Neretva/Croatia, June 17, 2020, [BibTeX, XML].

Keywords: Service Assurance, Service Exposure, AI
Abstract: Artificial Intelligence (AI) is widely applied in mobile and wireless networks to enhance network operation and service management. Advanced AI mechanisms often require high level of network service exposure in order to access data from as many network elements as possible and execute the AI recommended outcomes into the networks. However, in practice, it is not always feasible to expose the network services to 3rd parties or customers with AI ambitions. Considering that service assurance (SA) is a major area to which AI is applied, this paper describes how a closed-loop SA architecture is associated with the service exposure model in the 5G networks with network slicing. Then we investigate the impact and implication of service exposure on SA. Finally, a set of experiment results are provided to demonstrate the trade-off relationship between the AI ambition and the exposure level in SA.
URL: https://www.simula.no/file/eucnc2020pdf/download
MD5: b4a8e1df31b81c8c017ab352210a235d
Barik, Runa; Welzl, Michael; Fairhurst, Gorry; Dreibholz, Thomas; Elmokashfi, Ahmed Mustafa and Gjessing, Stein: ``On the Usability of Transport Protocols other than TCP: A Home Gateway and Internet Path Traversal Study´´ (PDF, 1887 KiB, 🇬🇧), in Computer Networks, vol. 173, Elsevier, DOI 10.1016/j.comnet.2020.107211, ISSN 1389-1286, May 22, 2020, [BibTeX, XML].

Keywords: Protocol Testing, SCTP, DCCP, UDP-Lite, NAT, Internet
Abstract: Network APIs are moving towards protocol agility, where applications express their needs but not a static protocol binding, and it is up to the layer below the API to choose a suitable protocol. The IETF Transport Services (TAPS) Working Group is standardizing a protocol-independent transport API and offering guidance to implementers. Apple’s recent “Network.framework” is specifically designed to allow such late and dynamic binding of protocols. When the network stack autonomously chooses and configures a protocol, it must first test which protocols are locally available and which work end-to-end (“protocol racing”). For this, it is important to know the set of available options, and which protocols should be tried first: Does it make sense to offer unchecked payload delivery, as with UDP-Lite? Is a UDP-based protocol like QUIC always a better choice, or should native SCTP be tried? This paper develops answers to such questions via (i) a NAT study in a local testbed, (ii) bidirectional Internet tests, (iii) a large scale Internet measurement campaign. The examined protocols are: SCTP, DCCP, UDP-Lite, UDP with a zero checksum and three different UDP encapsulations.
URL: https://www.simula.no/file/comnets2020pdf/download
MD5: 5ccb097435fedce9c617adeb99e5e5b0
Dreibholz, Thomas: ``Flexible 4G/5G Testbed Setup for Mobile Edge Computing using OpenAirInterface and Open Source MANO´´ (PDF, 228 KiB, 🇬🇧), in Proceedings of the 2nd International Workshop on Recent Advances for Multi-Clouds and Mobile Edge Computing (M2EC) in conjunction with the 34th International Conference on Advanced Information Networking and Applications (AINA), pp. 1143–1153, DOI 10.1007/978-3-030-44038-1_105, ISBN 978-3-030-44037-4, Caserta, Campania/Italy, April 15, 2020, [BibTeX, XML].

Keywords: Mobile Edge Computing, Network Function Virtualisation, Evolved Packet Core, Open Source MANO, OpenAirInterface, 5G
Abstract: Setting up a working 4G/5G mobile network development testbed can be a highly complicated and error-prone task. In this paper, we therefore introduce our open source Virtual Network Function (VNF) for an OpenAirInterface-based Evolved Packet Core (EPC) for deployment with the Open Source Management and Orchestration (Open Source MANO, OSM) framework. By using our VNF as basis, it will be easily possible to create own testbeds and extend them with further functionality, particularly – but not limited to – Mobile Edge Computing (MEC) setups. In a simple proof of concept, we demonstrate a basic transport protocol performance evaluation in a deployed test network.
URL: https://www.simula.no/file/m2ec2020pdf/download
MD5: 8af945e9913ec42f2d69d8a0fa22b42c
Dreibholz, Thomas: ``Easily Setting up 4G/5G Testbeds with OpenAirInterface using OSM´´ (PDF, 3100 KiB, 🇬🇧), Presentation at the OSM Hackfest, Madrid/Spain, March 11, 2020, [BibTeX, XML].

Keywords: Network Function Virtualisation, Evolved Packet Core, Open Source MANO, OpenAirInterface, 5G
Abstract: Setting up 4G/5G testbeds can be a highly complicated and error-prone task. In this presentation, we introduce our Open Source VNF and tool-chain for an OpenAirInterface-based EPC to be deployed with the OSM framework. Using our VNF and tool-chain as basis, it will be easily possible to create own testbeds, customise them and extend them with further functionalities.
URL: https://www.simula.no/file/osmhackfest9-presentationpdf/download
MD5: b2bdba640baf216815370dc8ad70734f

2019

Dreibholz, Thomas; Ferlin, Simone; Alay, Özgu; Elmokashfi, Ahmed Mustafa; Livadariu, Ioana Alexandrina and Zhou, Xing: ``MPTCP Experiences in the NorNet Testbed´´ (TXT, 26 KiB, 🇬🇧), Internet Draft draft-dreibholz-mptcp-nornet-experience-05, IETF, Individual Submission, December 3, 2019, [BibTeX, XML].

Abstract: This document collects some experiences of Multi-Path TCP (MPTCP) evaluations in the NorNet testbed.
URL: https://tools.ietf.org/id/draft-dreibholz-mptcp-nornet-experience-05.txt
MD5: 84e3873814b160ac557ccb4db7faca35
Dreibholz, Thomas; Tüxen, Michael; Shore, Melinda and Zong, Ning: ``The Applicability of Reliable Server Pooling (RSerPool) for Virtual Network Function Resource Pooling (VNFPOOL)´´ (TXT, 35 KiB, 🇬🇧), Internet Draft draft-dreibholz-vnfpool-rserpool-applic-09, IETF, Individual Submission, September 11, 2019, [BibTeX, XML].

Abstract: This draft describes the application of Reliable Server Pooling (RSerPool) for Virtual Network Function Resource Pooling (VNFPOOL).
URL: https://tools.ietf.org/id/draft-dreibholz-vnfpool-rserpool-applic-09.txt
MD5: 0bb6e37a9e2bdfc8ef26944f8871b28b
Barik, Runa; Welzl, Michael; Elmokashfi, Ahmed Mustafa; Dreibholz, Thomas; Islam, Safiqul and Gjessing, Stein: ``On the Utility of Unregulated IP DiffServ Code Point (DSCP) Usage by End Systems´´ (PDF, 1326 KiB, 🇬🇧), in Performance Evaluation, vol. 135, Elsevier, DOI 10.1016/j.peva.2019.102036, ISSN 0166-5316, August 26, 2019, [BibTeX, XML].

Keywords: DiffServ, DiffServ Code Point, QoS, WebRTC, Latency
Abstract: DiffServ was designed to implement service provider quality of service (QoS) policies, where routers change and react upon the DiffServ Code Point (DSCP) in the IP header. However, nowadays, applications are beginning to directly set the DSCP themselves, in the hope that this will yield a more appropriate service for their respective video, audio and data streams. WebRTC is a prime example of such an application. We present measurements, for both IPv4 and IPv6, of what happens to DSCP values along Internet paths after an end system has set them without any prior agreement between a customer and a service provider. We find that the DSCP is often changed or zeroed along the path, but detrimental effects from using the DSCP are extremely rare; moreover, DSCP values sometimes remain intact (potentially having an effect on traffic) for several AS hops. This positive result motivates an analysis of the potential latency impact from such DSCP usage, for which we present the first measurement results. We find that routers at approximately 3% of more than 100,000 links differentiate between the WebRTC DSCP values (EF, AF42 and CS1) and consistently reduce delay in comparison with probes carrying a zero value (CS0) under congestion. In contrast, routers at around 2% of these links increase the delay by a comparable amount under congestion, uniformly for EF, AF42 and CS1.
URL: https://www.simula.no/file/peva2019pdf/download
MD5: 399932a5294ce7b004f23b0e3c4f2df3
Elmokashfi, Ahmed Mustafa; Kvalbein, Amund; Dreibholz, Thomas and Jarvis, Chad: ``Norske mobilnett i 2018 – Tilstandsrapport fra Centre for Resilient Networks and Applications´´ (PDF, 24908 KiB, 🇳🇴), Simula Metropolitan Center for Digital Engineering, Centre for Resilient Networks and Applications (CRNA), ISBN 978-82-92593-25-7, Oslo/Norway, May 29, 2019, [BibTeX, XML].

Abstract: Denne rapporten er utarbeidet av Center for Resilient Networks and Applications (CRNA), som er en del av Simula Metropolitan Center for Digital Engineering. CRNA driver grunnleggende forskning innen robusthet og sikkerhet i nettverk med mandat og finansiering fra Samferdselsdepartementet. Senteret produserer en årlig rapport om tilstanden i norske mo- bilnett. Årets rapport er den sjette i rekken.
URL: https://www.simula.no/sites/default/files/crna-2018_0.pdf
MD5: d8522bafed20dee2b12d953f28bb5222
Dreibholz, Thomas: ``MELODIC at Hainan University: Combining NorNet Core with MELODIC´´ (PDF, 7379 KiB, 🇬🇧), Invited Talk at Hainan University, College of Information Science and Technology (CIST), Haikou, Hainan/People's Republic of China, April 18, 2019, [BibTeX, XML].

Keywords: Cloud Computing, MELODIC, Multi-Homing, NorNet Core, NorNet Testbed, OpenStack
Abstract: This talk gives a short overview over the possibilities of testing applications in the NorNet infrastructure. Furthermore, it presents a short overview of the ongoing work on integrating NorNet Core with the MELODIC multi-cloud infrastructure, including the NorNet Core setup at Hainan University and the Haikou College of Economics.
URL: https://www.simula.no/file/china2019-melodic-nornetcorepdf/download
MD5: 0daa0309becaa93ba0df66787bdac2fe
Dreibholz, Thomas: ``MELODIC at Hainan University: An Introduction to the MELODIC Project´´ (PDF, 8108 KiB, 🇬🇧), Keynote Talk at Hainan University, College of Information Science and Technology (CIST), Haikou, Hainan/People's Republic of China, April 17, 2019, [BibTeX, XML].

Keywords: Cloud Computing, MELODIC, OpenStack, Big Data, Applications
Abstract: In former times, it was necessary to operate and maintain powerful personal computers to run applications. Nowadays, many "normal" users just use laptops, tablet PCs or smartphones. Their applications are powered by cloud systems in the background, which are operated in data centres at remote locations and being connected over the Internet. This presentation first introduces the basics of cloud computing: virtualisation, virtual machines, containers, and software as a service. A challenge of using cloud computing is to deploy services to cloud providers, in order to operate them in a cost-efficient way while providing the best application experience to the users. The vision of the Multi-Cloud Execution-Ware for Large-scale Optimised Data-Intensive Computing (MELODIC) project is to enable federated cloud computing for data-intensive applications. Furthermore, it provides the user with an easy-to-use, unified cloud environment, which hides the complexity of a multi-cloud. The second part of this presentation therefore provides an overview of the basic ideas and application use cases of MELODIC.
URL: https://www.simula.no/file/china2019-melodic-introductionpdf/download
MD5: 931f7970895caa43236b89ddb370ddac
Dreibholz, Thomas: ``NorNet at Hainan University: Getting Started with NorNet Core´´ (PDF, 7286 KiB, 🇬🇧), Tutorial at Hainan University, College of Information Science and Technology (CIST), Haikou, Hainan/People's Republic of China, April 16, 2019, [BibTeX, XML].

Keywords: NorNet, NorNet Core, Testbed, Multi-Homing, Multi-Path Transport, Tutorial
Abstract: This tutorial – presented for students at the College of Information Science and Technology (CIST) at Hainan University – provides an introduction on how to get access to the NorNet Core testbed as well as how to run experiments in the testbed.
URL: https://www.simula.no/file/china2019-nornet-tutorialpdf/download
MD5: bfb88231c7e5c29d0343d3fed3f9a2bf
Dreibholz, Thomas: ``NorNet at Hainan University: From Simulations to Real-World Internet Measurements for Multi-Path Transport Research´´ (PDF, 17975 KiB, 🇬🇧), Keynote Talk at Hainan University, College of Information Science and Technology (CIST), Haikou, Hainan/People's Republic of China, April 15, 2019, [BibTeX, XML].

Keywords: NorNet, NorNet Core, NorNet Edge, Testbed, Multi-Homing, Introduction, Status
Abstract: A large fraction of the communication in the Internet is handled by the Transmission Control Protocol (TCP). Since the first deployments of this protocol more than 30 years ago, the spectrum of applications as well as the structure of the network have developed at a fast pace. For example, today's network devices, like smartphones and laptops – i.e. particularly many devices in the area of mobile computing – frequently have an interesting property: the existence of multiple IP addresses (IPv4 and/or IPv6). The addresses may even change due to mobility. This property, denoted as multi-homing, can be utilised for multi-path transport, i.e. the simultaneous usage of multiple paths in the network to improve performance. Multi-path transport is a hot topic in the Internet Engineering Task Force (IETF), which is the standardisation organisation for the Internet. This talk provides an overview of the work in the areas of multi-homing and multi-path transport, with focus on the area of the protocols TCP and Stream Control Transmission Protocol (SCTP) with their experimental extensions Multi-Path TCP (MPTCP) and Concurrent Multi-Path Transfer for SCTP (CMT-SCTP). It particularly shows the sequence of research and selected results, beginning from a simple simulation model, via lab setups and small Internet scenarios, up to the large-scale, international testbed project NorNet. NorNet, and particularly its landline network part NorNet Core, is furthermore described in some detail. Based on NorNet, it is finally possible to validate simulation results in real-world, multi-homed networks, in order to provide valuable input to the ongoing IETF standardisation processes of MPTCP and CMT-SCTP. Particularly, it will also show how the NorNet testbed can be utilised for research at Hainan University.
URL: https://www.simula.no/file/china2019-multipath-presentationpdf/download
MD5: e772349a001d337ecb15b28e34cefc86
Barik, Runa; Welzl, Michael; Fairhurst, Gorry; Dreibholz, Thomas; Elmokashfi, Ahmed Mustafa and Gjessing, Stein: ``Native SCTP, DCCP, UDP-Lite and Home Gateway NATs´´ (PDF, 80 KiB, 🇬🇧), in Proceedings of the 104th IETF Meeting, Praha/Czech Republic, March 28, 2019, [BibTeX, XML].

URL: https://datatracker.ietf.org/meeting/104/materials/slides-104-maprg-native-sctp-dccp-udp-lite-and-home-gateway-nats-runa-barik-01
MD5: 83992b2612501e88a1cb746e116b0e49
Luo, Yu; Zhou, Xing; Dreibholz, Thomas and Kuang, Hanbao: ``A Real-Time Video Streaming System over IPv6+MPTCP Technology´´ (PDF, 212 KiB, 🇬🇧), in Proceedings of the 1st International Workshop on Recent Advances for Multi-Clouds and Mobile Edge Computing (M2EC) in conjunction with the 33rd International Conference on Advanced Information Networking and Applications (AINA), pp. 1007–1019, DOI 10.1007/978-3-030-15035-8_99, ISBN 978-3-030-15034-1, Matsue, Shimane/Japan, March 27, 2019, [BibTeX, XML].

Keywords: Video Streaming Platform, IPv6, MPTCP, Load Balancing, Resilience
Abstract: Today, a steadily increasing number of users are not just passively consuming Internet content, but also share and publish content. Users publish text, photos and videos. With the availability of 5G high-speed, low-latency mobile broadband networks, real-time video streaming will also be possible. We believe this will become a very popular application in the coming years. But the more popular a service is, the higher the need for resilience. In this paper, we introduce our work-in-progress live video streaming platform for future mobile edge computing scenarios, which makes use of MPTCP+IPv6 to support multi-homing for resilience and multi-path transport for load balancing. As a proof of concept, we will show that the platform is (1) compatible with IPv6, (2) utilizes load balancing when possible and (3) provides robustness by network redundancy.
URL: https://www.simula.no/file/m2ec2019-videostreamingpdf/download
MD5: 724099429d06664fda7dab312b962cf2
Hong, Jiangshui; Dreibholz, Thomas; Schenkel, Joseph Adam and Hu, Jiaxi Alessia: ``An Overview of Multi-Cloud Computing´´ (PDF, 109 KiB, 🇬🇧), in Proceedings of the 1st International Workshop on Recent Advances for Multi-Clouds and Mobile Edge Computing (M2EC) in conjunction with the 33rd International Conference on Advanced Information Networking and Applications (AINA), pp. 1055–1068, DOI 10.1007/978-3-030-15035-8_103, ISBN 978-3-030-15034-1, Matsue, Shimane/Japan, March 27, 2019, [BibTeX, XML].

Keywords: Cloud Computing, Multi-Cloud, Hybrid Cloud, Federated Clouds, Big Data
Abstract: The purpose of this paper is to provide a brief overview of cloud computing technologies, particularly with respect to multi-cloud networks. First, the basics of cloud computing concepts are discussed. Next we outline some challenges facing cloud computing, and discuss how multi-cloud systems including multi-clouds, hybrid clouds, federated clouds, and cross-clouds may be used to deal with some of these issues. Finally, multi-cloud systems may also be used in conjunction with new developing technologies such as Big Data and Machine Learning, leading to exciting innovations. These are reviewed in brief. Our goal is to provide a modern look at the state of the art in multi-cloud computing and review open issues in the field. The goal is that this paper will help the reader to understand challenges facing cloud computing, how multi-cloud computing addresses some of these issues, and inspire community excitement at the future integration of multi-cloud platforms with other novel technologies.
URL: https://www.simula.no/file/m2ec2019-multicloudpdf-0/download
MD5: 505f5129e8c349000eb61cdb22572cf2
Dreibholz, Thomas; Mazumdar, Somnath; Zahid, Feroz; Taherkordi, Amirhosein and Gran, Ernst Gunnar: ``Mobile Edge as Part of the Multi-Cloud Ecosystem: A Performance Study´´ (PDF, 9966 KiB, 🇬🇧), in Proceedings of the 27th Euromicro International Conference on Parallel, Distributed and Network-Based Processing (PDP), pp. 59–66, DOI 10.1109/EMPDP.2019.8671599, ISBN 978-1-7281-1644-0, Pavia, Lombardia/Italy, February 13, 2019, [BibTeX, XML].

Keywords: Cloud Computing, Latency, Mobile Edge Computing, Multi-Cloud, Performance
Abstract: Cloud computing has revolutionized the way of application usage and deployment: applications run cost-effectively in remote data centers. With the increasing need for mobility and micro-services, particularly with the upcoming 5G mobile broadband networks, there is also a strong demand for mobile edge computing (MEC): applications run in small cloud systems in close proximity to the user, in order to minimize latencies. Both cloud and MEC have their advantages and disadvantages. Combining the two approaches in a unified multi-cloud, consisting of both traditional cloud services provisioned over heterogeneous cloud platforms and MEC systems, has the potential of obtaining the best out of both worlds. However, a comprehensive study is needed to evaluate the performance gains and the overheads involved for real-world cloud applications. In this paper, we introduce a baseline performance evaluation in order to identify the fallacies and pitfalls of combining multiple cloud systems and MEC into a unified MEC-multi-cloud platform. For this purpose, we analyze the basic, application-independent performance metrics of average round-trip time (RTT) and average application payload throughput in a setup consisting of two private and one public cloud systems. This baseline performance analysis confirms the feasibility of MEC-multi-cloud, and provides guidelines for designing an autonomic resource provisioning solutions, in terms of an extension proposed to our existing Melodic middleware platform for multi-cloud applications.
URL: https://www.simula.no/file/pdp2019-webpdf/download
MD5: ec3ccc12f5e74208bbcb2f363f019be9
Dreibholz, Thomas: ``NorNet at the University of Sydney: From Simulations to Real-World Internet Measurements for Multi-Path Transport Research´´ (PDF, 17078 KiB, 🇬🇧), Invited Talk at University of Sydney, Sydney, New South Wales/Australia, January 10, 2019, [BibTeX, XML].

Keywords: NorNet, NorNet Core, NorNet Edge, Testbed, Multi-Homing, Introduction, Status
Abstract: A large fraction of the communication in the Internet is handled by the Transmission Control Protocol (TCP). Since the first deployments of this protocol more than 30 years ago, the spectrum of applications as well as the structure of the network have developed at a fast pace. For example, today's network devices, like smartphones and laptops – i.e. particularly many devices in the area of mobile computing – frequently have an interesting property: the existence of multiple IP addresses (IPv4 and/or IPv6). The addresses may even change due to mobility. This property, denoted as multi-homing, can be utilised for multi-path transport, i.e. the simultaneous usage of multiple paths in the network to improve performance. Multi-path transport is a hot topic in the Internet Engineering Task Force (IETF), which is the standardisation organisation for the Internet. This talk provides an overview of the work in the areas of multi-homing and multi-path transport, with focus on the area of the protocols TCP and Stream Control Transmission Protocol (SCTP) with their experimental extensions Multi-Path TCP (MPTCP) and Concurrent Multi-Path Transfer for SCTP (CMT-SCTP). It particularly shows the sequence of research and selected results, beginning from a simple simulation model, via lab setups and small Internet scenarios, up to the large-scale, international testbed project NorNet. NorNet, and particularly its landline network part NorNet Core, is furthermore described in some detail. Based on NorNet, it is finally possible to validate simulation results in real-world, multi-homed networks, in order to provide valuable input to the ongoing IETF standardisation processes of MPTCP and CMT-SCTP. Particularly, it will also show how the NorNet testbed can be utilised for research at the University of Sydney.
URL: https://www.simula.no/file/sydney2019-presentationpdf/download
MD5: 8e5c35e9b396565a42c5cb24d208bd1f

2018

Tan, Qining; Yang, Xuelei; Zhao, Lan; Zhou, Xing and Dreibholz, Thomas: ``A Statistic Procedure to Find Formulae for Buffer Size in MPTCP´´ (PDF, 1747 KiB, 🇬🇧), in Proceedings of the 3rd IEEE Advanced Information Technology, Electronic and Automation Control Conference (IAEAC), pp. 900–907, DOI 10.1109/IAEAC.2018.8577570, ISBN 978-1-5386-4509-3, Chongqing/People's Republic of China, October 13, 2018, [BibTeX, XML].

Keywords: Multi-Path TCP (MPTCP), Buffer Size, Throughput, Statistical Predictive Modelling, Congestion Control
Abstract: It has been shown that the Multi-Path Transmission Control Protocol (MPTCP) can improve throughput, robustness and resilience of network transport. This paper seeks to discover the relationship of buffer size with throughput and congestion control algorithms, based on the statistical predictive modelling method. In spite of rapid growth of the implementations of MPTCP, the theoretical and fundamental question –- how large the buffer size of MPTCP should be to meet the network traffic -– remains unaddressed, although there were graphic illustrations and descriptive discussions about it.
URL: https://www.simula.no/file/iaeac2018-webpdf/download
MD5: aa33f9937c7cfa4a0e666d35986a5f48
Barik, Runa; Welzl, Michael; Elmokashfi, Ahmed Mustafa; Dreibholz, Thomas and Gjessing, Stein: ``Can WebRTC QoS Work? A DSCP Measurement Study´´ (PDF, 318 KiB, 🇬🇧), in Proceedings of the 30th International Teletraffic Congress (ITC), pp. 167–175, DOI 10.1109/ITC30.2018.00034, ISBN 978-0-9883045-5-0, Wien/Austria, September 6, 2018, [BibTeX, XML].

Keywords: Measurement, Fling, DSCP, Ingress, Egress
Abstract: DiffServ was designed to implement service provider quality of service (QoS) policies, where ingress and egress routers change the DiffServ Code Point (DSCP) in the IP header. However, nowadays, applications are beginning to directly set the DSCP themselves, in the hope that this will yield a more appropriate service for their respective video, audio and data streams. WebRTC is a prime example of such an application. As a first step towards understanding whether "WebRTC QoS works", we measured, for both IPv4 and IPv6, what happens to DSCP values along Internet paths. Our study is based on end-to-end measurements from 160 IPv4 and 65 IPv6 geographically spread controlled probe clients to 34 IPv4 and 18 IPv6 servers respectively. Clearly, when the DSCP value is changed, the net result may not be what the application desired. We find that this happens often, and conclude with recommendations on how to improve WebRTC and other applications using the DSCP.
URL: https://www.simula.no/file/itc30pdf/download
MD5: 61250e710bd427bef09802e076ff4185

2017

Dreibholz, Thomas: ``Big Data Applications on Multi-Clouds: An Introduction to the MELODIC Project´´ (PDF, 11377 KiB, 🇬🇧), Keynote Talk at Hainan University, College of Information Science and Technology (CIST), Haikou, Hainan/People's Republic of China, December 29, 2017, [BibTeX, XML].

Keywords: Cloud Computing, MELODIC, OpenStack, Big Data, Applications
Abstract: In former times, it was necessary to operate and maintain powerful personal computers to run applications. Nowadays, many "normal" users just use laptops, tablet PCs or smartphones. Their applications are powered by cloud systems in the background, which are operated in data centres at remote locations and being connected over the Internet. This presentation first introduces the basics of cloud computing: virtualisation, virtual machines, containers, and software as a service. A challenge of using cloud computing is to deploy services to cloud providers, in order to operate them in a cost-efficient way while providing the best application experience to the users. The vision of the Multi-Cloud Execution-Ware for Large-scale Optimised Data-Intensive Computing (MELODIC) project is to enable federated cloud computing for data-intensive applications. Furthermore, it provides the user with an easy-to-use, unified cloud environment, which hides the complexity of a multi-cloud. The second part of this presentation therefore provides an overview of the basic ideas and application use cases of MELODIC.
URL: https://www.simula.no/file/haikou2017-melodic-introductionpdf/download
MD5: 78406b60a0eb59d72adf177f427ed542
Dreibholz, Thomas: ``Combining NorNet Core with MELODIC´´ (PDF, 10777 KiB, 🇬🇧), Invited Talk at Hainan University, College of Information Science and Technology (CIST), Haikou, Hainan/People's Republic of China, December 29, 2017, [BibTeX, XML].

Keywords: Cloud Computing, MELODIC, Multi-Homing, NorNet Core, NorNet Testbed, OpenStack
Abstract: This talk gives a short overview over the possibilities of testing applications in the NorNet infrastructure. Furthermore, it presents a short overview of the ongoing work on integrating NorNet Core with the MELODIC multi-cloud infrastructure, including the NorNet Core setup at Hainan University and the Haikou College of Economics.
URL: https://www.simula.no/file/haikou2017-melodic-nornetcorepdf/download
MD5: 9ade823e423387685270004ad3561220
Dreibholz, Thomas: ``NEAT Tutorial at Hainan University: Getting Started with NEAT´´ (PDF, 3199 KiB, 🇬🇧), Invited Talk at Hainan University, College of Information Science and Technology (CIST), Haikou, Hainan/People's Republic of China, December 18, 2017, [BibTeX, XML].

Keywords: NEAT, NEAT Sockets API, Client, Server, Programming, Examples, NorNet Core
Abstract: The goal of NEAT (A New, Evolutive API and Transport-Layer Architecture for the Internet) is to allow network "services" offered to applications – such as reliability, low-delay communication or security – to be dynamically tailored based on application demands, current network conditions, hardware capabilities or local policies, and also to support the integration of new network functionality in an evolutionary fashion, without applications having to be rewritten. This talk gives a practical introduction to NEAT from a developer's perspective: after an introduction to NEAT, the APIs and in particular the NEAT Sockets API are explained. This is followed by pseudo-code examples and finally running-code examples. These running-code examples particularly also show how to use NEAT in NorNet Core
URL: https://www.simula.no/file/haikou2017-neat-tutorialpdf/download
MD5: 3a3d41b926ad3b6e7cad46b6f4372f7e
Dreibholz, Thomas: ``NorNet Core Beginner Tutorial at Hainan University´´ (PDF, 6963 KiB, 🇬🇧), Tutorial at Hainan University, College of Information Science and Technology (CIST), Haikou, Hainan/People's Republic of China, December 15, 2017, [BibTeX, XML].

Keywords: NorNet, NorNet Core, Testbed, Multi-Homing, Multi-Path Transport, Tutorial
Abstract: This tutorial – presented for students at the College of Information Science and Technology (CIST) at Hainan University – provides an introduction on how to get access to the NorNet Core testbed as well as how to run experiments in the testbed.
URL: https://www.simula.no/file/haikou2017-nornet-tutorialpdf-0/download
MD5: 4284520cbafcd9c10a67593dba9d1908
Dreibholz, Thomas: ``An Introduction to Multi-Path Transport at Hainan University´´ (PDF, 17946 KiB, 🇬🇧), Keynote Talk at Hainan University, College of Information Science and Technology (CIST), Haikou, Hainan/People's Republic of China, December 14, 2017, [BibTeX, XML].

Keywords: NorNet, NorNet Core, NorNet Edge, Testbed, Multi-Homing, Introduction, Status
Abstract: A large fraction of the communication in the Internet is handled by the Transmission Control Protocol (TCP). Since the first deployments of this protocol more than 30 years ago, the spectrum of applications as well as the structure of the network have developed at a fast pace. For example, today's network devices, like smartphones and laptops – i.e. particularly many devices in the area of mobile computing – frequently have an interesting property: the existence of multiple IP addresses (IPv4 and/or IPv6). The addresses may even change due to mobility. This property, denoted as multi-homing, can be utilised for multi-path transport, i.e. the simultaneous usage of multiple paths in the network to improve performance. Multi-path transport is a hot topic in the Internet Engineering Task Force (IETF), which is the standardisation organisation for the Internet. This talk provides an overview of the work in the areas of multi-homing and multi-path transport, with focus on the area of the protocols TCP and Stream Control Transmission Protocol (SCTP) with their experimental extensions Multi-Path TCP (MPTCP) and Concurrent Multi-Path Transfer for SCTP (CMT-SCTP). It particularly shows the sequence of research and selected results, beginning from a simple simulation model, via lab setups and small Internet scenarios, up to the large-scale, international testbed project NorNet. NorNet, and particularly its landline network part NorNet Core, is furthermore described in some detail. Based on NorNet, it is finally possible to validate simulation results in real-world, multi-homed networks, in order to provide valuable input to the ongoing IETF standardisation processes of MPTCP and CMT-SCTP. Particularly, it will also show how the NorNet testbed can be utilised for research at Hainan University.
URL: https://www.simula.no/file/haikou2017-multipath-presentationpdf-0/download
MD5: 8273d205aff530bb3ad845a98727310a
Dreibholz, Thomas: ``Testing Applications with the NorNet Infrastructure´´ (PDF, 11995 KiB, 🇬🇧), in Proceedings of the MELODIC Plenary Meeting, Warszawa, Masovia/Poland, September 21, 2017, [BibTeX, XML].

Keywords: Cloud Computing, MELODIC, Multi-Homing, NorNet Core, NorNet Testbed, OpenStack
Abstract: This talk gives a short overview over the possibilities of testing applications in the NorNet infrastructure. Furthermore, it presents a short overview of the ongoing work on integrating NorNet Core with the MELODIC multi-cloud infrastructure.
URL: https://www.simula.no/file/melodic-warsaw2017pdf/download
MD5: d7f500252a941682c5de800875a9e1c3
Weinrank, Felix; Grinnemo, Karl-Johan; Bozakov, Zdravko; Brunström, Anna; Dreibholz, Thomas; Hurtig, Per; Khademi, Naeem and Tüxen, Michael: ``A NEAT Way to Browse the Web´´ (PDF, 417 KiB, 🇬🇧), Demo Presentation, in Proceedings of the ACM, IRTF and ISOC Applied Networking Research Workshop (ANRW), pp. 33–34, DOI 10.1145/3106328.3106335, ISBN 978-1-4503-5108-9, Praha/Czech Republic, July 15, 2017, [BibTeX, XML].

Keywords: NEAT, Ossification, Transport Selection, Transport Service, SCTP, TCP
Abstract: There is a growing concern that the Internet transport layer has become ossified in the face of emerging novel applications, and that further evolution has become very difficult. The NEAT system is a novel and evolvable transport system that decouples applications from the underlying transport layer and network services. In so doing, it facilitates dynamic transport selection. This demo shows how the NEAT system is able to dynamically select the most appropriate transport solution for the Mozilla Firefox web browser.
URL: https://www.simula.no/file/anrw17-final13pdf/download
MD5: 88e5c2bc95ec7b070cf838734646bcfe
Dreibholz, Thomas: ``Multi-Path Transport at Hainan University – From Simulations to Real-World Internet Measurements in the NorNet Testbed´´ (PDF, 14797 KiB, 🇬🇧), Keynote Talk at Hainan University, College of Information Science and Technology (CIST), Haikou, Hainan/People's Republic of China, April 18, 2017, [BibTeX, XML].

Keywords: NorNet, NorNet Core, NorNet Edge, Testbed, Multi-Homing, Introduction, Status
Abstract: A large fraction of the communication in the Internet is handled by the Transmission Control Protocol (TCP). Since the first deployments of this protocol more than 30 years ago, the spectrum of applications as well as the structure of the network have developed at a fast pace. For example, today's network devices, like smartphones and laptops – i.e. particularly many devices in the area of mobile computing – frequently have an interesting property: the existence of multiple IP addresses (IPv4 and/or IPv6). The addresses may even change due to mobility. This property, denoted as multi-homing, can be utilised for multi-path transport, i.e. the simultaneous usage of multiple paths in the network to improve performance. Multi-path transport is a hot topic in the Internet Engineering Task Force (IETF), which is the standardisation organisation for the Internet. This talk provides an overview of the work in the areas of multi-homing and multi-path transport, with focus on the area of the protocols TCP and Stream Control Transmission Protocol (SCTP) with their experimental extensions Multi-Path TCP (MPTCP) and Concurrent Multi-Path Transfer for SCTP (CMT-SCTP). It particularly shows the sequence of research and selected results, beginning from a simple simulation model, via lab setups and small Internet scenarios, up to the large-scale, international testbed project NorNet. NorNet, and particularly its landline network part NorNet Core, is furthermore described in some detail. Based on NorNet, it is finally possible to validate simulation results in real-world, multi-homed networks, in order to provide valuable input to the ongoing IETF standardisation processes of MPTCP and CMT-SCTP. Particularly, it will also show how the NorNet testbed can be utilised for research at Hainan University.
URL: https://www.simula.no/file/haikou2017-multipath-presentationpdf/download
MD5: ece75d74aefc18d93d4ae7728ffadf5b
Dreibholz, Thomas: ``The Basics of Using the NorNet Core Testbed at Hainan University´´ (PDF, 4987 KiB, 🇬🇧), Tutorial at Hainan University, College of Information Science and Technology (CIST), Haikou, Hainan/People's Republic of China, April 18, 2017, [BibTeX, XML].

Keywords: NorNet, NorNet Core, Testbed, Multi-Homing, Multi-Path Transport, Tutorial
Abstract: This tutorial – presented for students at the College of Information Science and Technology (CIST) at Hainan University – provides an introduction on how to get access to the NorNet Core testbed as well as how to run experiments in the testbed.
URL: https://www.simula.no/file/haikou2017-nornet-tutorialpdf/download
MD5: dd54c96d743be34c823d3d26f2268a0d
Dreibholz, Thomas: ``A Practical Introduction to NEAT at Hainan University´´ (PDF, 866 KiB, 🇬🇧), Invited Talk at Hainan University, College of Information Science and Technology (CIST), Haikou, Hainan/People's Republic of China, April 17, 2017, [BibTeX, XML].

Keywords: NEAT, NEAT Sockets API, Client, Server, Programming, Examples, NorNet Core
Abstract: The goal of NEAT (A New, Evolutive API and Transport-Layer Architecture for the Internet) is to allow network "services" offered to applications – such as reliability, low-delay communication or security – to be dynamically tailored based on application demands, current network conditions, hardware capabilities or local policies, and also to support the integration of new network functionality in an evolutionary fashion, without applications having to be rewritten. This talk gives a practical introduction to NEAT from a developer's perspective: after an introduction to NEAT, the APIs and in particular the NEAT Sockets API are explained. This is followed by pseudo-code examples and finally running-code examples. These running-code examples particularly also show how to use NEAT in NorNet Core
URL: https://www.simula.no/file/haikou2017-neat-introductionpdf/download
MD5: 0da3ed198c7c49822d6626281f3dd270
Wang, Kun; Dreibholz, Thomas; Zhou, Xing; Fu, Fa; Tan, Yuyin; Cheng, Xi and Tan, Qining: ``On the Path Management of Multi-Path TCP in Internet Scenarios based on the NorNet Testbed´´ (PDF, 379 KiB, 🇬🇧), in Proceedings of the IEEE International Conference on Advanced Information Networking and Applications (AINA), pp. 1–8, DOI 10.1109/AINA.2017.29, ISBN 978-1-5090-6028-3, Taipei, Taiwan/People's Republic of China, March 27, 2017, [BibTeX, XML].

Keywords: Multi-Path Transport, Multi-Path TCP (MPTCP), Resilience, Path Management, Congestion Control, Configuration
Abstract: With the rapid development of Internet communications, there is a growing demand to support devices being connected to multiple Internet service providers simultaneously. For example, every modern smartphone already provides at least mobile broadband (UMTS, LTE) as well as Wi-Fi interfaces. This multi-homing property can be used for resilience, but there is also an increasing interest in making use of concurrent multi-path transport. That is, multiple network paths can be utilised simultaneously, in order to improve the payload throughput for applications like big data or cloud computing. In this paper, we examine the performance of multi-path transport in real-world Internet setups, based on Multi-Path TCP (MPTCP) in the NorNet testbed for multi-homed systems. However, systems in such challenging setups need proper configuration. Therefore, we particularly would like to highlight the performance impact of different path management and congestion control settings in such realistic scenarios.
URL: https://www.simula.no/file/kunwang-paper-webpdf/download
MD5: 28dbde48237a546a430f386474476c17
Zhou, Feng; Dreibholz, Thomas; Zhou, Xing; Fu, Fa; Tan, Yuyin and Gan, Quan: ``The Performance Impact of Buffer Sizes for Multi-Path TCP in Internet Setups´´ (PDF, 1006 KiB, 🇬🇧), in Proceedings of the IEEE International Conference on Advanced Information Networking and Applications (AINA), pp. 9–16, DOI 10.1109/AINA.2017.26, ISBN 978-1-5090-6028-3, Taipei, Taiwan/People's Republic of China, March 27, 2017, [BibTeX, XML].

Keywords: Multi-Path Transport, Multi-Path TCP (MPTCP), Buffer Size, Throughput, Robustness
Abstract: The Multi-Path Transmission Control Protocol (MPTCP) is the new concurrent multi-path transfer extension for the widely-deployed Transmission Control Protocol (TCP). Of course, having multiple and possibly highly dissimilar paths for transmission is a challenge for the management of the send and receive buffers, since optimal throughput is desired with a reasonable allocation of the limited memory resources in MPTCP endpoints. This is particularly important when many MPTCP connections have to be handled simultaneously. This paper measures out the required MPTCP buffer size in the real-world Internet testbed NorNet, comparing theoretical size and real size to analyse MPTCP performance. The experiment shows that multi-path transmission can effectively increase the application payload throughput, and greatly improve the robustness of the data transmission. As an important point of this paper, we can show that appropriate buffer size settings can increase the payload throughput, while not wasting resources. This paper has certain significance for further accurately determining the optimal buffer size settings for multi-path transmission in large-scale Internet setups.
URL: https://www.simula.no/file/fengzhou-mptcp-webpdf/download
MD5: a1ef777ccb72a3d160bd59fb377879ea
Dreibholz, Thomas: ``An Experiment Tutorial for the NorNet Core Testbed at the the Universidad de Castilla-La Mancha´´ (PDF, 5244 KiB, 🇬🇧), Tutorial at the Universidad de Castilla-La Mancha, Instituto de Investigación Informática de Albacete, Albacete, Castilla-La Mancha/Spain, February 16, 2017, [BibTeX, XML].

Keywords: NorNet, NorNet Core, Testbed, Multi-Homing, Multi-Path Transport, Tutorial
Abstract: This tutorial – presented for staff members and students at the Instituto de Investigación Informática de Albacete of the the Universidad de Castilla-La Mancha – provides an introduction on how to get access to the NorNet Core testbed as well as how to run experiments in the testbed.
URL: https://www.simula.no/file/uclm2017-nornet-tutorialpdf/download
MD5: fc137937a18e3b14ff370926de13c094
Dreibholz, Thomas: ``Multi-Path Transport – From Simulations to Real-World Internet Measurements´´ (PDF, 14631 KiB, 🇬🇧), Keynote Talk at the Universidad de Castilla-La Mancha, Instituto de Investigación Informática de Albacete, Albacete, Castilla-La Mancha/Spain, February 16, 2017, [BibTeX, XML].

Keywords: Multi-Path Transport, Multi-Path TCP (MPTCP), Concurrent Multi-Path Transfer for the Stream Control Transmission Protocol (CMT-SCTP), Simulations, Lab Measurements, Internet Measurements, NorNet Testbed, NorNet Core
Abstract: A large fraction of the communication in the Internet is handled by the Transmission Control Protocol (TCP). Since the first deployments of this protocol more than 30 years ago, the spectrum of applications as well as the structure of the network have developed at a fast pace. For example, today's network devices, like smartphones and laptops – i.e. particularly many devices in the area of mobile computing – frequently have an interesting property: the existence of multiple IP addresses (IPv4 and/or IPv6). The addresses may even change due to mobility. This property, denoted as multi-homing, can be utilised for multi-path transport, i.e. the simultaneous usage of multiple paths in the network to improve performance. Multi-path transport is a hot topic in the Internet Engineering Task Force (IETF), which is the standardisation organisation for the Internet. This talk provides an overview of the work in the areas of multi-homing and multi-path transport, with focus on the area of the protocols TCP and Stream Control Transmission Protocol (SCTP) with their experimental extensions Multi-Path TCP (MPTCP) and Concurrent Multi-Path Transfer for SCTP (CMT-SCTP). It particularly shows the sequence of research and selected results, beginning from a simple simulation model, via lab setups and small Internet scenarios, up to the large-scale, international testbed project NorNet. NorNet, and particularly its landline network part NorNet Core, is furthermore described in some detail. Based on NorNet, it is finally possible to validate simulation results in real-world, multi-homed networks, in order to provide valuable input to the ongoing IETF standardisation processes of MPTCP and CMT-SCTP.
URL: https://www.simula.no/file/uclm2017-multipath-presentationpdf-1/download
MD5: 288c43363ccf6276ba468ac04f76adfa
Dreibholz, Thomas: ``Multi-Path Transport with OMNeT++ and the INET Framework´´ (PDF, 4367 KiB, 🇬🇧), Invited Talk at the Universidad de Castilla-La Mancha, Instituto de Investigación Informática de Albacete, Albacete, Castilla-La Mancha/Spain, February 16, 2017, [BibTeX, XML].

Keywords: Multi-Path Transport, OMNeT++, INET Framework, Stream Control Transmission Protocol, SCTP, Concurrent Multipath Transfer, CMT, CMT-SCTP, NetPerfMeter, SimProcTC
Abstract: In order to evaluate the performance of multi-path transport protocols, a straightforward initial step is to perform simulations. OMNeT++, together with the INET Framework, provide a powerful Open Source platform for running network simulations. This talk provides an overview of simulating multi-path transport with OMNeT++ and the INET Framework. Particular focus is on the Concurrent Multipath Transfer extension for the Stream Control Transmission Protocol (SCTP). Furthermore, useful additions like the NetPerfMeter application model, the extended network auto-configurator as well as the Simulation Processing Tool-Chain (SimProcTC) are explained.
URL: https://www.simula.no/file/uclm2017-inet-presentationpdf/download
MD5: 3f419d15dbbf273d69067d6ab0b0aa07
Dreibholz, Thomas: ``An Experiment Tutorial for the NorNet Core Testbed at the University of Sydney´´ (PDF, 4829 KiB, 🇬🇧), Tutorial at University of Sydney, School of Information Technologies, Sydney, New South Wales/Australia, January 24, 2017, [BibTeX, XML].

Keywords: NorNet, NorNet Core, Testbed, Multi-Homing, Multi-Path Transport, Tutorial
Abstract: This tutorial – presented for Ph.D. students at the School of Information Technologies of the University of Sydney – provides an introduction on how to get access to the NorNet Core testbed as well as how to run experiments in the testbed.
URL: https://www.simula.no/file/sydney-tutorialpdf/download
MD5: d3154a5ac9aa2ec045c406d15ee51da7
Dreibholz, Thomas: ``NorNet at the University of Sydney – An Introduction to the NorNet Core Testbed´´ (PDF, 11848 KiB, 🇬🇧), Invited Talk at University of Sydney, School of Information Technologies, Sydney, New South Wales/Australia, January 24, 2017, [BibTeX, XML].

Keywords: NorNet, NorNet Core, Testbed, Multi-Homing, Introduction, Status
Abstract: Multi-homing denotes the simultaneous connection of endpoints (e.g. cloud servers, smartphones, etc.) to multiple Internet Service Providers (ISP). That is, the endpoints remain reachable even when some of the ISPs have problems (e.g. malfunction of hardware or break of cables). Besides the redundancy aspect, multi-homing can also make load sharing by multi-path transport possible, i.e. increasing the application throughput by utilising multiple paths simultaneously. Multi-path transport can e.g. be realised by Concurrent Multi-Path Transfer for SCTP (CMT-SCTP) and Multi-Path TCP (MPTCP), two protocols that are currently under standardisation in the IETF. The growing need for and deployment of multi-homed applications makes large-scale testing and evaluation in realistic Internet setups necessary. For instance, different paths can have very different characteristics with regard to bandwidth, packet loss rate, congestion, delay and jitter. Therefore, the NorNet project of the Simula Research Laboratory is building up an open platform for such experiments: the NorNet testbed. It provides programmable nodes with multiple ISP connections – wired as well as wireless – that are distributed all over Norway as well as some international locations. This talk will give an overview over NorNet's wired network part NorNet Core. Particularly, it will also show how the NorNet Core testbed can be utilised for research at the University of Sydney.
URL: https://www.simula.no/file/sydney2017-presentationpdf/download
MD5: e5f885e46a6b34b6fdcaf44fc77adde1

2016

Dreibholz, Thomas: ``NorNet – Building an Inter-Continental Internet Testbed based on Open Source Software´´ (PDF, 9587 KiB, 🇬🇧), in Proceedings of the LinuxCon Europe, Berlin/Germany, October 5, 2016, [BibTeX, XML].

Keywords: NorNet Testbed, Multi-Path Transport, Resilience, Virtualisation, Linux, Open Source
Abstract: NorNet is an open, international Internet testbed platform for research on multi-homed systems. Multi-homed systems have the property of being connected to multiple Internet Service Providers (ISP) simultaneously, in order to still provide connectivity in case of ISP/network failures. Basis of NorNet is Linux, together with other Open Source software. At the moment, the testbed infrastructure spreads over 21 sites on 4 continents. NorNet makes extensive use of advanced Linux features like virtualisation, file system features, routing rules, SCTP, MPTCP, and more. The global distribution creates further challenges. Goal of this talk is therefore to provide an overview of the problems that occurred when building the testbed, as well as solutions and lessons learned from solving these challenges. The idea is to present guidelines for utilising the advanced Linux features in own projects.
URL: https://www.simula.no/file/linuxcon2016-presentationpdf/download
MD5: 835722bb90f2cf4e0aab67be150396b5
Yedugundla, Kiran Venkata; Ferlin, Simone; Dreibholz, Thomas; Alay, Özgü; Kuhn, Nicolas; Hurtig, Per and Brunström, Anna: ``Is Multi-Path Transport Suitable for Latency Sensitive Traffic?´´ (PDF, 4525 KiB, 🇬🇧), in Computer Networks, vol. 105, pp. 1–21, Elsevier, DOI 10.1016/j.comnet.2016.05.008, ISSN 1389-1286, August 4, 2016, [BibTeX, XML].

Keywords: Internet, Latency, Multi-Path Communication, Transport Protocols, MPTCP, CMT-SCTP
Abstract: This paper assesses whether multi-path communication can help latency-sensitive applications to satisfy the requirements of their users. We consider Concurrent Multi-path Transfer for SCTP (CMT-SCTP) and Multi-Path TCP (MPTCP) and evaluate their proficiency in transporting video, gaming, and web traffic over combinations of WLAN and 3G interfaces. To ensure the validity of our evaluation, several experimental approaches were used including simulation, emulation and live experiments. When paths are symmetric in terms of capacity, delay and loss rate, we find that the experienced latency is significantly reduced, compared to using a single path. Using multiple asymmetric paths does not affect latency – applications do not experience any increase or decrease, but might benefit from other advantages of multi-path communication. In the light of our conclusions, multi-path transport is suitable for latency-sensitive traffic and mature enough to be widely deployed.
URL: https://www.simula.no/file/comnets2016-multipathsurveypdf/download
MD5: 568dbefc09c209fa4d5598258d7f0831
Dreibholz, Thomas: ``NorNet – The Internet Testbed for Multi-Homed Systems´´ (PDF, 11198 KiB, 🇬🇧), in Proceedings of the Multi-Service Networks Conference (MSN, Coseners), Abingdon, Oxfordshire/United Kingdom, July 8, 2016, [BibTeX, XML].

Keywords: NorNet, NorNet Core, NorNet Edge, Testbed, Multi-Homing, Introduction, Overview
Abstract: Multi-homing denotes the simultaneous connection of endpoints (e.g. cloud servers, smartphones, etc.) to multiple Internet Service Providers (ISP). That is, the endpoints remain reachable even when some of the ISPs have problems (e.g. malfunction of hardware or break of cables). Besides the redundancy aspect, multi-homing can also make load sharing by multi-path transport possible, i.e. increasing the application throughput by utilising multiple paths simultaneously. Multi-path transport can e.g. be realised by Concurrent Multi-Path Transfer for SCTP (CMT-SCTP) and Multi-Path TCP (MPTCP), two protocols that are currently under standardisation in the IETF. The growing need for and deployment of multi-homed applications makes large-scale testing and evaluation in realistic Internet setups necessary. For instance, different paths can have very different characteristics with regard to bandwidth, packet loss rate, congestion, delay and jitter. Therefore, the NorNet project of the Simula Research Laboratory is building up an open platform for such experiments: the NorNet testbed. It provides programmable nodes with multiple ISP connections – wired as well as wireless – that are distributed all over Norway as well as some international locations. This talk will give an overview over NorNet.
URL: https://www.simula.no/file/msn2016-presentationpdf/download
MD5: 693855de478247f1b9ac6be6e93c2af5
Dreibholz, Thomas: ``NorNet at the Haikou College of Economics – An Introduction to the NorNet Testbed´´ (PDF, 10163 KiB, 🇬🇧), Invited Talk at the Haikou College of Economics, Guilinyang, Hainan/People's Republic of China, June 6, 2016, [BibTeX, XML].

Keywords: NorNet, NorNet Core, NorNet Edge, Testbed, Multi-Homing, Introduction, Status
Abstract: Multi-homing denotes the simultaneous connection of endpoints (e.g. cloud servers, smartphones, etc.) to multiple Internet Service Providers (ISP). That is, the endpoints remain reachable even when some of the ISPs have problems (e.g. malfunction of hardware or break of cables). Besides the redundancy aspect, multi-homing can also make load sharing by multi-path transport possible, i.e. increasing the application throughput by utilising multiple paths simultaneously. Multi-path transport can e.g. be realised by Concurrent Multi-Path Transfer for SCTP (CMT-SCTP) and Multi-Path TCP (MPTCP), two protocols that are currently under standardisation in the IETF. The growing need for and deployment of multi-homed applications makes large-scale testing and evaluation in realistic Internet setups necessary. For instance, different paths can have very different characteristics with regard to bandwidth, packet loss rate, congestion, delay and jitter. Therefore, the NorNet project of the Simula Research Laboratory is building up an open platform for such experiments: the NorNet testbed. It provides programmable nodes with multiple ISP connections – wired as well as wireless – that are distributed all over Norway as well as some international locations. This talk will give an overview over NorNet. Particularly, it will also show how the NorNet testbed can be utilised for research at the Haikou College of Economics.
URL: https://www.simula.no/file/haikou2016-hkc-presentationpdf/download
MD5: 2df3a5eec4fffe610a7ac773c8c2056c
Dreibholz, Thomas: ``An Experiment Tutorial for the NorNet Core Testbed at Hainan University´´ (PDF, 5054 KiB, 🇬🇧), Tutorial at Hainan University, College of Information Science and Technology (CIST), Haikou, Hainan/People's Republic of China, May 29, 2016, [BibTeX, XML].

Keywords: NorNet, NorNet Core, Testbed, Multi-Homing, Multi-Path Transport, Tutorial
Abstract: This tutorial – presented for students at the College of Information Science and Technology (CIST) at Hainan University – provides an introduction on how to get access to the NorNet Core testbed as well as how to run experiments in the testbed.
URL: https://www.simula.no/file/haikou2016-hainanuniversity-tutorialpdf-0/download
MD5: 29995f8cc5514f8bcbb9725816ff2bde
Dreibholz, Thomas: ``NorNet at Hainan University – An Introduction to the NorNet Testbed´´ (PDF, 13828 KiB, 🇬🇧), Invited Talk at Hainan University, College of Information Science and Technology (CIST), Haikou, Hainan/People's Republic of China, May 29, 2016, [BibTeX, XML].

Keywords: NorNet, NorNet Core, NorNet Edge, Testbed, Multi-Homing, Introduction, Status
Abstract: Multi-homing denotes the simultaneous connection of endpoints (e.g. cloud servers, smartphones, etc.) to multiple Internet Service Providers (ISP). That is, the endpoints remain reachable even when some of the ISPs have problems (e.g. malfunction of hardware or break of cables). Besides the redundancy aspect, multi-homing can also make load sharing by multi-path transport possible, i.e. increasing the application throughput by utilising multiple paths simultaneously. Multi-path transport can e.g. be realised by Concurrent Multi-Path Transfer for SCTP (CMT-SCTP) and Multi-Path TCP (MPTCP), two protocols that are currently under standardisation in the IETF. The growing need for and deployment of multi-homed applications makes large-scale testing and evaluation in realistic Internet setups necessary. For instance, different paths can have very different characteristics with regard to bandwidth, packet loss rate, congestion, delay and jitter. Therefore, the NorNet project of the Simula Research Laboratory is building up an open platform for such experiments: the NorNet testbed. It provides programmable nodes with multiple ISP connections – wired as well as wireless – that are distributed all over Norway as well as some international locations. This talk will give an overview over NorNet. Particularly, it will also show how the NorNet testbed can be utilised for research at Hainan University.
URL: https://www.simula.no/file/haikou2016-hainanuniversity-presentationpdf/download
MD5: 4b42984be60a62d83f35537c32b4313f
Ferlin, Simone; Alay, Özgü; Hayes, David Andrew; Dreibholz, Thomas and Welzl, Michael: ``Revisiting Congestion Control for Multipath TCP with Shared Bottleneck Detection´´ (PDF, 1440 KiB, 🇬🇧), in Proceedings of the 35th IEEE International Conference on Computer Communications (INFOCOM), pp. 2419–2427, ISBN 978-1-4673-9953-1, San Francisco, California/U.S.A., April 14, 2016, [BibTeX, XML].

Keywords: Multi-Path TCP (MPTCP), Shared Bottleneck Detection, Congestion Control, Coupled Congestion Control
Abstract: Multipath TCP (MPTCP) enables the simultaneous usage of multiple links for bandwidth aggregation, better resource utilization and improved reliability. Its coupled congestion control intends to reap the increased bandwidth of multiple links, while avoiding to be more aggressive than regular TCP flows on every used link. We argue that this leads to a very conservative behavior when paths do not share a bottleneck. Therefore, in this paper, we first quantify the penalty of the coupled congestion control for the links that do not share a bottleneck. Then, in order to overcome this penalty, we design and implement a practical shared bottleneck detection (SBD) algorithm for MPTCP, namely MPTCP-SBD. Through extensive emulations, we show that MPTCP-SBD outperforms all currently deployed MPTCP coupled congestion controls by accurately detecting bottlenecks resulting in throughput gains of up to 30\% in the absence of shared bottlenecks while remaining fair to TCP in shared bottlenecks scenarios. We complement the emulation results with real-network experiments justifying it is safeness for deployment.
URL: https://www.simula.no/file/infocom2016-webpdf/download
MD5: f60e8b176a4f13b368211d222ddc1969
Dreibholz, Thomas: ``An Experiment Tutorial for the NorNet Core Testbed at HAW Hamburg´´ (PDF, 4134 KiB, 🇬🇧), Tutorial at Hochschule für Angewandte Wissenschaften Hamburg (HAW Hamburg), Hamburg/Germany, March 22, 2016, [BibTeX, XML].

Keywords: NorNet, NorNet Core, Testbed, Multi-Homing, Multi-Path Transport, Tutorial
Abstract: This tutorial – presented at the Hochschule für Angewandte Wissenschaften Hamburg (HAW Hamburg) – provides an introduction on how to get access to the NorNet Core testbed as well as how to run experiments in the testbed.
URL: https://www.simula.no/file/hawhamburg2016-tutorialpdf/download
MD5: 46cc11c5168a96e4b30c0737c82158f1
Dreibholz, Thomas: ``NorNet at HAW Hamburg – An Introduction to the NorNet Testbed´´ (PDF, 13981 KiB, 🇬🇧), Invited Talk at Hochschule für Angewandte Wissenschaften Hamburg (HAW Hamburg), Hamburg/Germany, March 22, 2016, [BibTeX, XML].

Keywords: NorNet, NorNet Core, NorNet Edge, Testbed, Multi-Homing, Introduction, Status
Abstract: Multi-homing denotes the simultaneous connection of endpoints (e.g. cloud servers, smartphones, etc.) to multiple Internet Service Providers (ISP). That is, the endpoints remain reachable even when some of the ISPs have problems (e.g. malfunction of hardware or break of cables). Besides the redundancy aspect, multi-homing can also make load sharing by multi-path transport possible, i.e. increasing the application throughput by utilising multiple paths simultaneously. Multi-path transport can e.g. be realised by Concurrent Multi-Path Transfer for SCTP (CMT-SCTP) and Multi-Path TCP (MPTCP), two protocols that are currently under standardisation in the IETF. The growing need for and deployment of multi-homed applications makes large-scale testing and evaluation in realistic Internet setups necessary. For instance, different paths can have very different characteristics with regard to bandwidth, packet loss rate, congestion, delay and jitter. Therefore, the NorNet project of the Simula Research Laboratory is building up an open platform for such experiments: the NorNet testbed. It provides programmable nodes with multiple ISP connections – wired as well as wireless – that are distributed all over Norway as well as some international locations. This talk will give an overview over NorNet. Particularly, it will also show how the NorNet testbed can be utilised for research at the Hochschule für Angewandte Wissenschaften Hamburg (HAW Hamburg)
URL: https://www.simula.no/file/hawhamburg2016-presentationpdf/download
MD5: 49c17f620cbfe46758e8f02f4e553081
Dreibholz, Thomas: ``An Experiment Tutorial for the NorNet Core Testbed at NICTA´´ (PDF, 4140 KiB, 🇬🇧), Tutorial at National Information Communications Technology Australia (NICTA), Sydney, New South Wales/Australia, January 22, 2016, [BibTeX, XML].

Keywords: NorNet, NorNet Core, Testbed, Multi-Homing, Multi-Path Transport, Tutorial
Abstract: This tutorial – presented at National Information Communications Technology Australia (NICTA) – provides an introduction on how to get access to the NorNet Core testbed as well as how to run experiments in the testbed.
URL: https://www.simula.no/file/nicta2016-tutorialpdf/download
MD5: a4017ee0d66b87416e5c0c8921d94957
Dreibholz, Thomas: ``NorNet at NICTA – An Introduction to the NorNet Testbed´´ (PDF, 13403 KiB, 🇬🇧), Invited Talk at National Information Communications Technology Australia (NICTA), Sydney, New South Wales/Australia, January 22, 2016, [BibTeX, XML].

Keywords: NorNet, NorNet Core, NorNet Edge, Testbed, Multi-Homing, Introduction, Status
Abstract: Multi-homing denotes the simultaneous connection of endpoints (e.g. cloud servers, smartphones, etc.) to multiple Internet Service Providers (ISP). That is, the endpoints remain reachable even when some of the ISPs have problems (e.g. malfunction of hardware or break of cables). Besides the redundancy aspect, multi-homing can also make load sharing by multi-path transport possible, i.e. increasing the application throughput by utilising multiple paths simultaneously. Multi-path transport can e.g. be realised by Concurrent Multi-Path Transfer for SCTP (CMT-SCTP) and Multi-Path TCP (MPTCP), two protocols that are currently under standardisation in the IETF. The growing need for and deployment of multi-homed applications makes large-scale testing and evaluation in realistic Internet setups necessary. For instance, different paths can have very different characteristics with regard to bandwidth, packet loss rate, congestion, delay and jitter. Therefore, the NorNet project of the Simula Research Laboratory is building up an open platform for such experiments: the NorNet testbed. It provides programmable nodes with multiple ISP connections – wired as well as wireless – that are distributed all over Norway as well as some international locations. This talk will give an overview over NorNet. Particularly, it will also show how the NorNet testbed can be utilised for research at National Information Communications Technology Australia (NICTA)
URL: https://www.simula.no/file/nicta2016-presentationpdf/download
MD5: 553d4072d3381f6d460a73f25ddfb77f

2015

Fu, Fa; Zhou, Xing; Dreibholz, Thomas; Wang, Keying; Zhou, Feng and Gan, Quan: ``Performance Comparison of Congestion Control Strategies for Multi-Path TCP in the NorNet Testbed´´ (PDF, 172 KiB, 🇬🇧), in Proceedings of the 4th IEEE/CIC International Conference on Communications in China (ICCC), pp. 607–612, DOI 10.1109/ICCChina.2015.7448667, ISBN 978-1-5090-0243-6, Shenzhen, Guangdong/People's Republic of China, November 3, 2015, [BibTeX, XML].

Keywords: Multi-Path Transport, Multi-Path TCP (MPTCP), Congestion Control, Performance Analysis
Abstract: Multi-path transport has become a hot topic in Internet protocol research with the evolution of emerging technologies, particularly with the market penetration of access terminals having multiple network interfaces (e.g. smartphones with LTE/UMTS and Wi-Fi interfaces). Multi-Path TCP (MPTCP) is an extension of TCP that allows a connection to create several subflows for utilizing multiple network paths. Using multiple end-to-end TCP connections as subflows, MPTCP distributes data to different subflows over multiple ISPs, so as to enhance network robustness and improve throughput. This paper first presents MPTCP’s architecture and multi-path congestion control algorithm concepts. Then, it examines three test scenarios in the NorNet testbed, particularly highlighting the performance difference between using uncoupled and coupled congestion controls in multi-homed, real-world Internet setups. The results show that MPTCP with coupled CCs gets more benefits than TCP and demonstrates the lower aggressiveness in comparison to MPTCP with uncoupled CCs.
URL: https://www.simula.no/file/fufa-mptcp-webpdf/download
MD5: caabd753ddce037e04e81dbffbd0ad82
Dreibholz, Thomas: ``The NorNet Experimentation Platform for Multi-Homed Systems´´ (PDF, 14369 KiB, 🇬🇧), in Proceedings of the NORDUnet Technical Workshop (NTW), København/Denmark, September 17, 2015, [BibTeX, XML].

Keywords: NorNet, NorNet Core, NorNet Edge, Testbed, Multi-Homing, Introduction, Status
Abstract: Multi-homing denotes the simultaneous connection of endpoints (e.g. cloud servers, smartphones, etc.) to multiple Internet Service Providers (ISP). That is, the endpoints remain reachable even when some of the ISPs have problems (e.g. malfunction of hardware or break of cables). Besides the redundancy aspect, multi-homing can also make load sharing by multi-path transport possible, i.e. increasing the application throughput by utilising multiple paths simultaneously. Multi-path transport can e.g. be realised by Concurrent Multi-Path Transfer for SCTP (CMT-SCTP) and Multi-Path TCP (MPTCP), two protocols that are currently under standardisation in the IETF. The growing need for and deployment of multi-homed applications makes large-scale testing and evaluation in realistic Internet setups necessary. For instance, different paths can have very different characteristics with regard to bandwidth, packet loss rate, congestion, delay and jitter. Therefore, the NorNet project of the Simula Research Laboratory is building up an open platform for such experiments: the NorNet testbed. It provides programmable nodes with multiple ISP connections – wired as well as wireless – that are distributed all over Norway as well as some international locations. This talk will give an overview over NorNet. Particularly, it will also show how the NorNet testbed can be utilised for research by the Nordic community.
URL: https://www.simula.no/file/ntw2015pdf/download
MD5: 2a3f1bda015fcf850cd2f5adb3571cad
Dreibholz, Thomas: ``NetPerfMeter: A Network Performance Metering Tool´´ (HTML, 20 KiB, 🇬🇧), in Multipath TCP Blog, September 7, 2015, [BibTeX, XML].

Keywords: Software, NetPerfMeter, Multi-Path Transfer, Multi-Path TCP (MPTCP)
Abstract: A common problem for evaluating multiple transport protocols in a multi-platform environment is to have a test tool that is capable to run in all these environments, and – of course – to support all necessary protocols. Using different evaluation tools is not a good solution, since each tool may introduce its own – and possibly incompatible – parametrisation scheme. In order to overcome this problem, originally for the use case of evaluating the Stream Control Transmission Protocol (SCTP) and compare it to the Transmission Control Protocol (TCP), NetPerfMeter has been designed and developed. This blog article provides an introduction to NetPerfMeter.
URL: http://blog.multipath-tcp.org/blog/html/2015/09/07/netperfmeter.html
MD5: 383ce2668d7de6ea2da8083be8eacfcd
Adhari, Hakim; Dreibholz, Thomas; Werner, Sebastian and Rathgeb, Erwin Paul: ``Eclipse: A New Dynamic Delay-based Congestion Control Algorithm for Background Traffic´´ (PDF, 1082 KiB, 🇬🇧), in Proceedings of the 18th International Conference on Network-Based Information Systems (NBiS), pp. 115–123, DOI 10.1109/NBiS.2015.21, ISBN 978-1-4799-9942-2, Taipei/Taiwan, September 2, 2015, [BibTeX, XML]. Awarded with the Best Paper Award.

Keywords: Background Traffic, Congestion Control, Delay-based Congestion Control, Less-than-Best-Effort Service
Abstract: Initially, the Internet transport protocol TCP has been designed to provide a ``best effort'' service: it is meant to share the network resources with other users and applications. However, there is nowadays also a growing demand for transmitting big amounts of data in the background, namely background transport that uses spare capacity, but with minimal effect on other traffic. For instance, systems can proactively download content that the user/system would need in the future (e.g. update packages, video files, etc.). Efforts have therefore been made in the IETF for the sake of such a service with Low Extra Delay Background Traffic (LEDBAT) congestion control. While LEDBAT works in some cases, there are however known situations where it causes serious performance problems, particularly in combination with the ubiquitous bufferbloat for example in current broadband networks. In this paper, we analyse the issues of LEDBAT and propose a new approach for background traffic. Inspired by an astronomical event, we have named this approach Eclipse. Unlike LEDBAT, Eclipse can dynamically adapt to the network characteristics not only to minimise the additional network delay but also to maximise the utilisation of spare network capacity. We will show the usefulness of Eclipse by simulations.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/Forschung/NBIS2015-Eclipse.pdf
MD5: d189576ba3280e5a18c578e807edbbee
Dreibholz, Thomas: ``The NorNet Core Testbed: A Status Update for the NNUW-3´´ (PDF, 12120 KiB, 🇬🇧), in Proceedings of the 3rd International NorNet Users Workshop (NNUW-3), Fornebu, Akershus/Norway, August 28, 2015, [BibTeX, XML].

Keywords: NorNet, NorNet Core, Testbed, Multi-Homing, Multi-Path Transport, Status
Abstract: This talk provides an update on the NorNet Core testbed development and research for the 3rd NorNet Users Workshop (NNUW-3) in August 2015.
URL: https://www.simula.no/file/nnuw3-dreibholzpdf/download
MD5: 6137dcfde02ba8d35ed6db1d17cf4b17
Dreibholz, Thomas: ``MPTCP Experiences in the NorNet Testbed: draft-dreibholz-mptcp-nornet-experience-01´´ (PDF, 12798 KiB, 🇬🇧), in Proceedings of the 93th IETF Meeting, Praha/Czech Republic, July 21, 2015, [BibTeX, XML].

Keywords: NorNet, Multi-Path TCP (MPTCP), Experiences
Abstract: This presentation gives an overview of the Multi-Path TCP (MPTCP) experiences from recent research in the NorNet testbed.
URL: https://www.simula.no/file/ietf93-presentationpdf/download
MD5: 65887764fb8f954949ee47abf20b06ec
Livadariu, Ioana Alexandrina; Ferlin, Simone; Alay, Özgü; Dreibholz, Thomas; Dhamdhere, Amogh and Elmokashfi, Ahmed Mustafa: ``Leveraging the IPv4/IPv6 Identity Duality by using Multi-Path Transport´´ (PDF, 327 KiB, 🇬🇧), in Proceedings of the 18th IEEE Global Internet Symposium (GI) at the 34th IEEE Conference on Computer Communications (INFOCOM), pp. 312–317, DOI 10.1109/INFCOMW.2015.7179403, ISBN 978-1-4673-7131-5, Hong Kong/People's Republic of China, April 27, 2015, [BibTeX, XML].

Keywords: Identity Duality, IPv4, IPv6, Internet Paths, Routing
Abstract: With the 20th anniversary of IPv6 nearing quickly, a growing number of Internet service providers (ISPs) now offer their customers both IPv6 and IPv4 connectivity. This makes multi-homing with IPv4 and IPv6 increasingly common even with just a single ISP connection. Furthermore, the growing popularity of multi-path transport, especially Multi-Path TCP (MPTCP) that is the extension of the well-known Transmission Control Protocol (TCP), leads to the question of whether this identity duality can be utilized for improving application performance in addition to providing resilience. In this paper, we first investigate the AS-level congruency of IPv4 and IPv6 paths in the Internet. We find that more than 60\% of the current IPv4 and IPv6 AS-paths are non-congruent at the AS-level, which motivates us to explore how MPTCP can utilize the IPv4/IPv6 identity duality to improve data transfer performance. Our results show that MPTCP, even with a single dual-stack Internet connection, can significantly improve the end-to-end performance when the underlying paths are non-congruent. The extent of the improvement can reach up to the aggregate of the IPv4 and IPv6 bandwidth.
URL: https://www.simula.no/file/gis2015pdf-0/download
MD5: 62683a568c45c655151216105a168310
Dreibholz, Thomas; Bjørgeengen, Jarle and Werme, Jonas: ``Monitoring and Maintaining the Infrastructure of the NorNet Testbed for Multi-Homed Systems´´ (PDF, 538 KiB, 🇬🇧), in 5th International Workshop on Protocols and Applications with Multi-Homing Support (PAMS), pp. 611–616, DOI 10.1109/WAINA.2015.76, ISBN 978-1-4799-1775-4, Gwangju/South Korea, March 25, 2015, [BibTeX, XML].

Keywords: NorNet, Internet Testbed, Monitoring, Multi-Homing, Path Characteristics, Resilience
Abstract: NorNet Core is the world's first, open, large-scale Internet testbed for multi-homed systems and applications. Particularly, it is currently used for research on topics like multi-path transport and resilience. Researchers can run experiments on distributed, programmable nodes that are distributed over various locations and providing access to multiple different Internet service providers (ISP) with different access technologies. Clearly, a key feature of this testbed is to work in the real-world Internet. That is, it is especially desired to expose experiments to real Internet behaviour like background traffic. However, for the researcher, it is necessary to actually know how paths – being used for an experiment – actually behave: Are the paths actually working? How are the round-trip times among sites over different ISPs, etc.. How did the behaviour change over time? To provide such information to the researchers, we have designed and developed a maintenance and monitoring infrastructure for the NorNet Core testbed. In this paper, we will first introduce this infrastructure. Furthermore, we will demonstrate its usefulness with some useful, real-world examples. Our infrastructure has now become part of the testbed, and it is therefore available for all users of NorNet Core as well.
URL: https://www.simula.no/file/pams2015-nornet-monitoring-webpdf/download
MD5: de8568f766023dba008bb7201f92b6a3
Dreibholz, Thomas; Zhou, Xing and Fu, Fa: ``Multi-Path TCP in Real-World Setups – An Evaluation in the NorNet Core Testbed´´ (PDF, 211 KiB, 🇬🇧), in 5th International Workshop on Protocols and Applications with Multi-Homing Support (PAMS), pp. 617–622, DOI 10.1109/WAINA.2015.74, ISBN 978-1-4799-1775-4, Gwangju/South Korea, March 25, 2015, [BibTeX, XML].

Keywords: NorNet, Multi-Path TCP (MPTCP), Multi-Homing, Multi-Path Transport, Evaluation
Abstract: Nowadays, cloud applications are becoming more and more popular. However, in order for such applications to work, they need a stable Internet connectivity. To avoid the Internet access becoming a single point of failure, redundancy by multi-homing – i.e. simultaneous access to multiple Internet service providers (ISP) – is becoming increasingly common as well. Multi-homing leads to the desire to utilise all network attachment points simultaneously, which is e.g. provided by the Multi-Path TCP (MPTCP) extension for TCP. MPTCP is still under development by researchers and standardisation in the IETF. Particularly, it is necessary to evaluate MPTCP under realistic Internet conditions. NorNet Core is the world's first, large-scale Internet testbed for multi-homed systems and applications. It is therefore a useful platform for evaluating MPTCP. In this paper, we therefore present our NorNet Core extension that adds MPTCP support to the testbed. Particularly, our extension is now available to all users of NorNet Core as well, which significantly reduces the effort of MPTCP researchers to evaluate MPTCP and its improvements. In a proof of concept, we furthermore show the strengths and weaknesses of state-of-the-art MPTCP in NorNet Core, in a configuration covering 29 ISP connections at 14 sites in 5 different countries.
URL: https://www.simula.no/file/pams2015-mptcp-webpdf/download
MD5: 1d87843d61fd55880aa7aa25fba51e19
Dreibholz, Thomas: ``The NorNet Testbed – A Large-Scale Experiment Platform for Real-World Experiments with Multi-Homed Systems´´ (PDF, 6771 KiB, 🇬🇧), Invited Talk at Swinburne University, Centre for Advanced Internet Architectures (CAIA), Melbourne, Victoria/Australia, January 29, 2015, [BibTeX, XML].

Keywords: NorNet, NorNet Core, NorNet Edge, Testbed, Multi-Homing, Introduction, Status
Abstract: Multi-homing denotes the simultaneous connection of endpoints (e.g. cloud servers, smartphones, etc.) to multiple Internet Service Providers (ISP). That is, the endpoints remain reachable even when some of the ISPs have problems (e.g. malfunction of hardware or break of cables). Besides the redundancy aspect, multi-homing can also make load sharing by multi-path transport possible, i.e. increasing the application throughput by utilising multiple paths simultaneously. Multi-path transport can e.g. be realised by Concurrent Multi-Path Transfer for SCTP (CMT-SCTP) and Multi-Path TCP (MPTCP), two protocols that are currently under standardisation in the IETF. The growing need for and deployment of multi-homed applications makes large-scale testing and evaluation in realistic Internet setups necessary. For instance, different paths can have very different characteristics with regard to bandwidth, packet loss rate, congestion, delay and jitter. Therefore, the NorNet project of the Simula Research Laboratory is building up an open platform for such experiments: the NorNet testbed. It provides programmable nodes with multiple ISP connections – wired as well as wireless – that are distributed all over Norway as well as some international locations. This talk will give an overview over NorNet. Particularly, it will also show how the NorNet testbed can be utilised for research at the Centre for Advanced Internet Architectures (CAIA) of Swinburne University
URL: https://www.simula.no/file/caia2015-presentation-webpdf/download
MD5: 2794c56370ccbe3a10e6d72ba7ec9c76
Dreibholz, Thomas: ``NorNet at NICTA – An Open, Large-Scale Testbed for Multi-Homed Systems´´ (PDF, 6545 KiB, 🇬🇧), Invited Talk at National Information Communications Technology Australia (NICTA), Sydney, New South Wales/Australia, January 15, 2015, [BibTeX, XML].

Keywords: NorNet, NorNet Core, NorNet Edge, Testbed, Multi-Homing, Introduction, Status
Abstract: Multi-homing denotes the simultaneous connection of endpoints (e.g. cloud servers, smartphones, etc.) to multiple Internet Service Providers (ISP). That is, the endpoints remain reachable even when some of the ISPs have problems (e.g. malfunction of hardware or break of cables). Besides the redundancy aspect, multi-homing can also make load sharing by multi-path transport possible, i.e. increasing the application throughput by utilising multiple paths simultaneously. Multi-path transport can e.g. be realised by Concurrent Multi-Path Transfer for SCTP (CMT-SCTP) and Multi-Path TCP (MPTCP), two protocols that are currently under standardisation in the IETF. The growing need for and deployment of multi-homed applications makes large-scale testing and evaluation in realistic Internet setups necessary. For instance, different paths can have very different characteristics with regard to bandwidth, packet loss rate, congestion, delay and jitter. Therefore, the NorNet project of the Simula Research Laboratory is building up an open platform for such experiments: the NorNet testbed. It provides programmable nodes with multiple ISP connections – wired as well as wireless – that are distributed all over Norway as well as some international locations. This talk will give an overview over NorNet with a focus on its usage for research on multi-path transport. Particularly, it will also show how the NorNet testbed can be utilised for research at NICTA.
URL: https://www.simula.no/file/nicta2015-presentation-webpdf/download
MD5: 377dc3c9d7d13031bab6c3dbb4e54309

2014

Ferlin, Simone; Dreibholz, Thomas and Alay, Özgü: ``Multi-Path Transport over Heterogeneous Wireless Networks: Does it really pay off?´´ (PDF, 986 KiB, 🇬🇧), in Proceedings of the IEEE Global Communications Conference (GLOBECOM), pp. 4807–4813, DOI 10.1109/GLOCOM.2014.7037567, ISBN 978-1-4799-3512-3, Austin, Texas/U.S.A., December 11, 2014, [BibTeX, XML].

Keywords: Multi-Path Transport, Multi-Path TCP, Heterogeneous Networks, Mobile Broadband, Performance
Abstract: Multi-path transfer protocols such as Concurrent Multi-Path Transfer for SCTP and Multi-Path TCP (MPTCP), are becoming increasingly popular due to widespread deployment of smartphones with multi-homing support. Although the idea of using multiple interfaces simultaneously to improve application throughput is tempting, does transmission over multiple interfaces always provide benefits especially in realistic setup? In this paper, we first show that multi-path transfer might actually have a negative impact in real-world scenarios with mobile broadband and wireless LAN networks. We then introduce our Dynamic Relative Path Scoring (DRePaS) algorithm that continuously evaluates the contribution of paths to the overall performance and dynamically influences the scheduling decisions to make best use of the paths for the overall system performance. We show that DRePaS outperforms the current MPTCP implementation in terms of throughput and application delay, especially when the links are heterogeneous.
URL: https://www.simula.no/file/simulasimula2884pdf/download
MD5: 5a0ad1ae3594f3818c63345173b9fc1e
Dreibholz, Thomas; Simonsen, Henrik Vest and Gran, Ernst Gunnar: ``A Demonstration of the NorNet Core Research Testbed for Multi-Homed Systems´´ (PDF, 60 KiB, 🇬🇧), Demo Presentation at the IEEE Global Communications Conference (GLOBECOM), Austin, Texas/U.S.A., December 9, 2014, [BibTeX, XML].

Keywords: Demonstration, NorNet Core, Testbed, Multi-Homing, Multi-Path Transport, Resilience
Abstract: This abstract describes a demonstration proposal for the NorNet Core testbed for multi-homed systems.
URL: https://www.simula.no/file/simulasimula2868pdf/download
MD5: e94511a7807546cd2c2acf7c6e438f9d
Golkar, Forough; Dreibholz, Thomas and Kvalbein, Amund: ``Measuring and Comparing Internet Path Stability in IPv4 and IPv6´´ (PDF, 436 KiB, 🇬🇧), in Proceedings of the 5th IEEE International Conference on the Network of the Future (NoF), pp. 1–5, DOI 10.1109/NOF.2014.7119767, ISBN 978-1-4799-7531-0, Paris/France, December 4, 2014, [BibTeX, XML]. Awarded with the Best Paper Award.

Keywords: NorNet Core, Internet, IPv4, IPv6, Path Stability, Resilience, Robustness
Abstract: In just about 4 years, IPv6 will celebrate its 20th anniversary. While the protocol itself is already quite old, its deployment has only recently picked up speed. Not so many Internet service providers offer direct IPv6 connectivity to their customers, yet. Clearly, when IPv6 is available to customers, they expect that IPv6 offers at least the same – or even better – stability of connections in comparison to IPv4. The main goal of this paper is to investigate whether this is true today. In our paper, we present up-to-date measurement results on the stability of IPv4 and IPv6 paths in the real Internet, based on machines that are distributed over a large geographical area, as part of the NorNet Core testbed infrastructure for multi-homed systems. The measurements not only cover high-speed research networks, but also consumer-grade ADSL connections – i.e. the ISP connection types of "normal" end-users – as well as a broad range of different ISPs. The measurements show that IPv6 paths are less stable than corresponding IPv4 paths. We also find that the use of load balancing is more prevalent in IPv6 than in IPv4.
URL: https://www.simula.no/file/simulasimula3048pdf/download
MD5: e94bfd5f13ed1ab81ac86b90fc1bbfe1
Dreibholz, Thomas: ``The NorNet Testbed at Tsinghua University – A Large-Scale Experiment Platform for Real-World Experiments with Multi-Homed Systems´´ (PDF, 12148 KiB, 🇬🇧), Invited Talk at Tsinghua University, Department of Computer Science, Beijing/People's Republic of China, October 30, 2014, [BibTeX, XML].

Keywords: NorNet, NorNet Core, NorNet Edge, Testbed, Multi-Homing, Introduction, Status
Abstract: Multi-homing denotes the simultaneous connection of endpoints (e.g. cloud servers, smartphones, etc.) to multiple Internet Service Providers (ISP). That is, the endpoints remain reachable even when some of the ISPs have problems (e.g. malfunction of hardware or break of cables). Besides the redundancy aspect, multi-homing can also make load sharing by multi-path transport possible, i.e. increasing the application throughput by utilising multiple paths simultaneously. Multi-path transport can e.g. be realised by Concurrent Multi-Path Transfer for SCTP (CMT-SCTP) and Multi-Path TCP (MPTCP), two protocols that are currently under standardisation in the IETF. The growing need for and deployment of multi-homed applications makes large-scale testing and evaluation in realistic Internet setups necessary. For instance, different paths can have very different characteristics with regard to bandwidth, packet loss rate, congestion, delay and jitter. Therefore, the NorNet project of the Simula Research Laboratory is building up an open platform for such experiments: the NorNet testbed. It provides programmable nodes with multiple ISP connections – wired as well as wireless – that are distributed all over Norway as well as some international locations. This talk will give an overview over NorNet. Particularly, it will also show how the NorNet testbed can be utilised for research at Tsinghua University.
URL: https://www.simula.no/file/haikou2014-tsinghuauniversity-presentationpdf/download
MD5: 27d10f08d47acba206ede3b0e4ba6286
Dreibholz, Thomas: ``An Experiment Tutorial for the NorNet Core Testbed at Hainan University´´ (PDF, 2148 KiB, 🇬🇧), Tutorial at Hainan University, College of Information Science and Technology (CIST), Haikou, Hainan/People's Republic of China, October 27, 2014, [BibTeX, XML].

Keywords: NorNet, NorNet Core, Testbed, Multi-Homing, Multi-Path Transport, Tutorial
Abstract: This tutorial – presented for students at the College of Information Science and Technology (CIST) at Hainan University – provides an introduction on how to get access to the NorNet Core testbed as well as how to run experiments in the testbed.
URL: https://www.simula.no/file/simulasimula3078pdf/download
MD5: d884e2a243b307e85ce712583812d798
Dreibholz, Thomas: ``The NorNet Testbed at Qiongzhou University – A Large-Scale Experiment Platform for Real-World Experiments with Multi-Homed Systems´´ (PDF, 7475 KiB, 🇬🇧), Invited Talk at Qiongzhou University, Sanya, Hainan/People's Republic of China, October 25, 2014, [BibTeX, XML].

Keywords: NorNet, NorNet Core, NorNet Edge, Testbed, Multi-Homing, Introduction, Status
Abstract: Multi-homing denotes the simultaneous connection of endpoints (e.g. cloud servers, smartphones, etc.) to multiple Internet Service Providers (ISP). That is, the endpoints remain reachable even when some of the ISPs have problems (e.g. malfunction of hardware or break of cables). Besides the redundancy aspect, multi-homing can also make load sharing by multi-path transport possible, i.e. increasing the application throughput by utilising multiple paths simultaneously. Multi-path transport can e.g. be realised by Concurrent Multi-Path Transfer for SCTP (CMT-SCTP) and Multi-Path TCP (MPTCP), two protocols that are currently under standardisation in the IETF. The growing need for and deployment of multi-homed applications makes large-scale testing and evaluation in realistic Internet setups necessary. For instance, different paths can have very different characteristics with regard to bandwidth, packet loss rate, congestion, delay and jitter. Therefore, the NorNet project of the Simula Research Laboratory is building up an open platform for such experiments: the NorNet testbed. It provides programmable nodes with multiple ISP connections – wired as well as wireless – that are distributed all over Norway as well as some international locations. This talk will give an overview over NorNet. Particularly, it will also show how the NorNet testbed can be utilised for research at Qiongzhou University.
URL: https://www.simula.no/file/haikou2014-qiongzhouuniversity-presentationpdf/download
MD5: 4431f323f43a1010eb2ba371e72f6b92
Dreibholz, Thomas: ``The NorNet Testbed at Hainan University – A Large-Scale Experiment Platform for Real-World Experiments with Multi-Homed Systems´´ (PDF, 11940 KiB, 🇬🇧), Invited Talk at Hainan University, College of Information Science and Technology (CIST), Haikou, Hainan/People's Republic of China, October 20, 2014, [BibTeX, XML].

Keywords: NorNet, NorNet Core, NorNet Edge, Testbed, Multi-Homing, Introduction, Status
Abstract: Multi-homing denotes the simultaneous connection of endpoints (e.g. cloud servers, smartphones, etc.) to multiple Internet Service Providers (ISP). That is, the endpoints remain reachable even when some of the ISPs have problems (e.g. malfunction of hardware or break of cables). Besides the redundancy aspect, multi-homing can also make load sharing by multi-path transport possible, i.e. increasing the application throughput by utilising multiple paths simultaneously. Multi-path transport can e.g. be realised by Concurrent Multi-Path Transfer for SCTP (CMT-SCTP) and Multi-Path TCP (MPTCP), two protocols that are currently under standardisation in the IETF. The growing need for and deployment of multi-homed applications makes large-scale testing and evaluation in realistic Internet setups necessary. For instance, different paths can have very different characteristics with regard to bandwidth, packet loss rate, congestion, delay and jitter. Therefore, the NorNet project of the Simula Research Laboratory is building up an open platform for such experiments: the NorNet testbed. It provides programmable nodes with multiple ISP connections – wired as well as wireless – that are distributed all over Norway as well as some international locations. This talk will give an overview over NorNet. Particularly, it will also show how the NorNet testbed can be utilised for research at Hainan University.
URL: https://www.simula.no/file/haikou2014-hainanuniversity-presentationpdf/download
MD5: 3f83db1821d33b72dc869ac7a86aa094
Dreibholz, Thomas: ``The NorNet Testbed – An Overview for the GENI Meeting´´ (PDF, 21055 KiB, 🇬🇧), Invited Talk for the GENI Meeting at the Kungliga Tekniska högskolan (KTH), Stockholm/Sweden, September 15, 2014, [BibTeX, XML].

Keywords: NorNet, NorNet Core, NorNet Edge, Testbed, Multi-Homing, Multi-Path Transport, Overview
Abstract: Multi-homing denotes the simultaneous connection of endpoints (e.g. cloud servers, smartphones, etc.) to multiple Internet Service Providers (ISP). That is, the endpoints remain reachable even when some of the ISPs have problems (e.g. malfunction of hardware or break of cables). Besides the redundancy aspect, multi-homing can also make load sharing by multi-path transport possible, i.e. increasing the application throughput by utilising multiple paths simultaneously. Multi-path transport can e.g. be realised by Concurrent Multi-Path Transfer for SCTP (CMT-SCTP) and Multi-Path TCP (MPTCP), two protocols that are currently under standardisation in the IETF. The growing need for and deployment of multi-homed applications makes large-scale testing and evaluation in realistic Internet setups necessary. For instance, different paths can have very different characteristics with regard to bandwidth, packet loss rate, congestion, delay and jitter. Therefore, the NorNet project of the Simula Research Laboratory is building up an open platform for such experiments: the NorNet testbed. It consists of two parts: the wired part NorNet Core as well as the wireless part NorNet Edge, both parts provide programmable nodes with multiple ISP connections. These nodes are distributed all over Norway as well as some international locations. This talk will give an overview over the NorNet testbed and how it can be utilised for research on multi-homed systems.
URL: https://www.simula.no/file/simulasimula3008pdf/download
MD5: 3a4da9d27f89a7e6fd722230116b4e55
Dreibholz, Thomas: ``An Experiment Tutorial for the NorNet Core Testbed´´ (PDF, 6033 KiB, 🇬🇧), in Proceedings of the 2nd International NorNet Users Workshop (NNUW-2), Fornebu, Akershus/Norway, August 29, 2014, [BibTeX, XML].

Keywords: NorNet, NorNet Core, Testbed, Multi-Homing, Multi-Path Transport, Tutorial
Abstract: This tutorial provides an introduction on how to get access to the NorNet Core testbed as well as how to run experiments in the testbed.
URL: https://www.simula.no/file/simulasimula2938pdf/download
MD5: 9711b4f32dd9a2c4946aa4aeceeac31c
Alay, Özgü; Ferlin, Simone and Dreibholz, Thomas: ``Multipath Transport over Heterogeneous Networks´´ (PDF, 2930 KiB, 🇬🇧), in Proceedings of the 2nd International NorNet Users Workshop (NNUW-2), Fornebu, Akershus/Norway, August 29, 2014, [BibTeX, XML].

URL: https://www.simula.no/file/simulasimula2970pdf/download
MD5: 3b1f2c76b82d27ee2eb7c4830a489783
Dreibholz, Thomas: ``The NorNet Core Testbed – Introduction and Status in August 2014´´ (PDF, 14850 KiB, 🇬🇧), in Proceedings of the 2nd International NorNet Users Workshop (NNUW-2), Fornebu, Akershus/Norway, August 28, 2014, [BibTeX, XML].

Keywords: NorNet, NorNet Core, Testbed, Multi-Homing, Multi-Path Transport, Introduction
Abstract: This talk provides an introduction to the NorNet Core testbed as well as a status overview on the development and deployment in August 2014.
URL: https://www.simula.no/file/simulasimula2936pdf/download
MD5: e2f018deb04a839bf93f842bb729d012
Aziz, Adnan; Hoffstadt, Dirk; Rathgeb, Erwin Paul and Dreibholz, Thomas: ``A Distributed Infrastructure to Analyse SIP Attacks in the Internet´´ (PDF, 728 KiB, 🇬🇧), in Proceedings of the IFIP Networking Conference, pp. 1–9, DOI 10.1109/IFIPNetworking.2014.6857088, ISBN 978-3-901882-58-6, Trondheim, Sør-Trøndelag/Norway, June 4, 2014, [BibTeX, XML].

Keywords: VoIP, SIP, SIP Trace Recorder, Misuse, Fraud, Security, Honeynet, Honeypot, Sensor, NorNet, Toll Fraud, Misuse Detection
Abstract: VoIP systems, based on the Session Initiation Protocol (SIP), are becoming more and more widespread in the Internet. However, this creates security issues and opens up new opportunities for misuse and fraud. The most widespread threat are multi-stage attacks to commit Toll Fraud. To devise effective countermeasures, it is crucial to know how attacks on these systems are performed in reality. In this paper, we introduce a novel distributed monitoring system with Sensor nodes located in Norway, Germany and China that allow to detect SIP-based attacks from the Internet. Based on experiences from experiments spanning several years, we propose a new setup which allows simple and straightforward addition of new remote observation points. We have deployed this setup in the NorNet testbed and highlight its advantages compared to a previous setup with physically distributed Sensors. We also present results from a 45 day field test with 13 observation points. These results confirm the advantages of a widely distributed monitoring setup and give some new insights into the behavior of the attackers.
URL: https://www.tdr.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/Forschung/A_Distributed_Infrastructure_to_Analyse_SIP_Attacks_in_the_Internet.pdf
MD5: 06d871da35e30c555878c0f619268135
Ferlin, Simone; Dreibholz, Thomas and Alay, Özgü: ``Tackling the Challenge of Bufferbloat in Multi-Path Transport over Heterogeneous Wireless Networks´´ (PDF, 820 KiB, 🇬🇧), in Proceedings of the IEEE/ACM International Symposium on Quality of Service (IWQoS), pp. 123–128, DOI 10.1109/IWQoS.2014.6914310, ISBN 978-1-4799-4852-9, Hong Kong/People's Republic of China, May 26, 2014, [BibTeX, XML].

Keywords: Multi-Path Transport, Performance, Bufferbloat, Mobile Broadband Networks, MPTCP, NorNet Edge
Abstract: Today, most of the smart phones are equipped with two network interfaces: Mobile Broadband (MBB) and Wireless Local Area Network (WLAN). Multi-path transport protocols provide increased throughput or reliability, by utilizing these interfaces simultaneously. However, multi-path transmission over networks with very different QoS characteristics is a challenge. In this paper, we studied Multi-Path TCP (MPTCP) in heterogeneous networks, specifically MBB networks and WLAN. We first investigate the effect of bufferbloat in MBB on MPTCP performance. Then, we propose a bufferbloat mitigation algorithm: Multi-Path Transport Bufferbloat Mitigation (MPT-BM). Using our algorithm, we conduct experiments in real operational networks. The experimental results show that MPT-BM outperforms the current MPTCP implementation by increasing the application goodput quality and decreasing MPTCP's buffer delay, jitter and buffer space requirements.
URL: https://www.simula.no/file/simulasimula2722pdf/download
MD5: 41fdb83e1fa929ad9523504ea7b43402
Adhari, Hakim; Werner, Sebastian; Dreibholz, Thomas and Rathgeb, Erwin Paul: ``LEDBAT-MP – On the Application of Lower-than-Best-Effort for Concurrent Multipath Transfer´´ (PDF, 1229 KiB, 🇬🇧), in Proceedings of the 4th International Workshop on Protocols and Applications with Multi-Homing Support (PAMS), DOI 10.1109/WAINA.2014.125, ISBN 978-1-4799-2652-7, Victoria, British Columbia/Canada, May 16, 2014, [BibTeX, XML].

Keywords: Multi-Path Transfer, Congestion Control, Background Traffic, CMT-SCTP, MPTCP
Abstract: The Internet is based on best effort communication, i.e. it tries to deliver packets but does not provide any guarantees. A transport protocol can make use of this best effort service to provide a suitable service to its applications. Also, its congestion control is responsible for a fair distribution of the resources within the Internet. However, background data transfer applications (like file sharing or update fetching) do not require "best effort", they in fact could use a "lower-than-best-effort" service to leave resources to more important applications if needed. For this purpose, the Low Extra Delay Background Transport (LEDBAT) algorithm has been standardized by the IETF. Nowadays, multi-homing is becoming increasingly common in modern networks and several approaches to exploit this feature (e.g. CMT-SCTP, MPTCP) have evolved that are able to combine resources of multiple paths. For background traffic oriented algorithms like LEDBAT, this feature could be of great use, too, i.e. by increasing the overall bandwidth while shifting the transmission away from paths which are used by other flows. This could be particularly useful for non-critical bulk transfers in data centres. In this paper, we introduce our approach LEDBAT for Multi-Path – denoted as LEDBAT-MP – and analyze its performance by simulations. With this paper, we want to highlight some generic design questions and start a discussion on how a solid universal background multi-path congestion control strategy should behave.
URL: https://www.simula.no/file/simulasimula2512pdf/download
MD5: dfdfcfef3b476f3d9aad8215ef058662
Ferlin, Simone; Dreibholz, Thomas; Alay, Özgü and Kvalbein, Amund: ``Measuring the QoS Characteristics of Operational 3G Mobile Broadband Networks´´ (PDF, 1524 KiB, 🇬🇧), in Proceedings of the 4th International Workshop on Protocols and Applications with Multi-Homing Support (PAMS), pp. 753–758, DOI 10.1109/WAINA.2014.123, ISBN 978-1-4799-2652-7, Victoria, British Columbia/Canada, May 16, 2014, [BibTeX, XML].

Keywords: Multi-Path Transport, Mobile Broadband Networks, Performance, Measurements, Quality of Service
Abstract: Today, many smart phones and tablets have multiple interfaces (i.e. WLAN and 3G). These multiple interfaces can be utilized simultaneously by a multi-path transport protocol to provide bandwidth aggregation or reliability. However, in order to design efficient multi-path scheduling and congestion control strategies, it is crucial to understand the behaviour and properties of the underlying paths first. WLAN links have already been studied extensively in the literature. Therefore, in this paper, we focus on Mobile Broadband (MBB) networks that are in use today. We utilized NorNet Edge nodes that are connected to up to five different 3G ISPs (UMTS and CDMA2000), hence, providing a realistic view on the QoS characteristics that are experienced by end-users of these MBB networks. We present QoS characteristics (e.g. bandwidth, delay and loss) and discuss our observations. Our results shed light on what a multi-path transport endpoint has to expect – and to efficiently cope with – when using today's MBB networks as transport paths.
URL: https://www.simula.no/file/simulasimula2516pdf/download
MD5: 829e385c146f959a11e21b9e0f816091
Dreibholz, Thomas: ``The NorNet Testbed for Multi-Homed Systems – Overview and Status´´ (PDF, 8480 KiB, 🇬🇧), Invited Talk at the University of British Columbia (UBC), Vancouver, British Columbia/Canada, May 12, 2014, [BibTeX, XML].

Keywords: NorNet, NorNet Core, NorNet Edge, Testbed, Multi-Homing, Introduction, Status
Abstract: Multi-homing denotes the simultaneous connection of endpoints (e.g. cloud servers, smartphones, etc.) to multiple Internet Service Providers (ISP). That is, the endpoints remain reachable even when some of the ISPs have problems (e.g. malfunction of hardware or break of cables). Besides the redundancy aspect, multi-homing can also make load sharing by multi-path transport possible, i.e. increasing the application throughput by utilising multiple paths simultaneously. Multi-path transport can e.g. be realised by Concurrent Multi-Path Transfer for SCTP (CMT-SCTP) and Multi-Path TCP (MPTCP), two protocols that are currently under standardisation in the IETF. The growing need for and deployment of multi-homed applications makes large-scale testing and evaluation in realistic Internet setups necessary. For instance, different paths can have very different characteristics with regard to bandwidth, packet loss rate, congestion, delay and jitter. Therefore, the NorNet project of the Simula Research Laboratory is building up an open platform for such experiments: the NorNet testbed. It provides programmable nodes with multiple ISP connections – wired as well as wireless – that are distributed all over Norway as well as some international locations. This talk will give an overview over NorNet with a focus on its usage for research on multi-path transport. Particularly, it will also show how the NorNet testbed can be utilised for research at the University of British Columbia (UBC).
URL: https://www.simula.no/file/simulasimula2740pdf/download
MD5: 07b62bbfd0da20550fcd31a3b3269b24
Dreibholz, Thomas: ``The NorNet Testbed for Multi-Homed Systems – Introduction and Status´´ (PDF, 8480 KiB, 🇬🇧), Invited Talk at Princeton University, Department of Computer Science, Princeton, New Jersey/U.S.A., May 8, 2014, [BibTeX, XML].

Keywords: NorNet, NorNet Core, NorNet Edge, Testbed, Multi-Homing, Introduction, Status
Abstract: Multi-homing denotes the simultaneous connection of endpoints to multiple Internet Service Providers (ISP). That is, such endpoints should remain reachable even when some of the ISPs have problems. Besides the redundancy aspect, multi-homing can also make load sharing by multi-path transport possible, i.e. increasing the application throughput by utilizing multiple paths simultaneously. The growing need for and deployment of multi-homed applications makes large-scale testing and evaluation in realistic Internet setups necessary. For instance, different paths can have very different characteristics with regard to bandwidth, packet loss rate, congestion, delay and jitter. Therefore, the Simula Research Laboratory is building up the NorNet testbed, which is an open platform for such experiments. NorNet consists of two parts, the wireless part NorNet Edge as well as the wired part NorNet Core, providing researchers the possibility to use programmable, multi-homed nodes at different locations in Norway as well as at some international sites. This talk gives an overview over the NorNet testbed, with a special focus on the usage of the PlanetLab/Linux Containers-based software that is used to run NorNet Core.
URL: https://www.simula.no/file/simulasimula2730pdf/download
MD5: b60311d5e6fb7858da54836e82aa3a67
Dreibholz, Thomas: ``The NorNet Testbed – Overview and Selected Results from Multi-Path Transport Research´´ (PDF, 6432 KiB, 🇬🇧), Invited Talk at the New York University (NYU), Polytechnic School of Engineering, Brooklyn, New York/U.S.A., May 5, 2014, [BibTeX, XML].

Keywords: NorNet, NorNet Core, NorNet Edge, Testbed, Multi-Homing, Overview, Research, Multi-Path TCP, MPTCP
Abstract: Multi-homing denotes the simultaneous connection of endpoints (e.g. cloud servers, smartphones, etc.) to multiple Internet Service Providers (ISP). That is, the endpoints remain reachable even when some of the ISPs have problems (e.g. malfunction of hardware or break of cables). Besides the redundancy aspect, multi-homing can also make load sharing by multi-path transport possible, i.e. increasing the application throughput by utilising multiple paths simultaneously. In order to evaluate and test mulit-homed systems, the Simula Research Laboratory is currently building up the NorNet testbed. It consists of distributed research nodes located all over the country of Norway as well as some international locations, providing researchers the possibility to run experiments in real-world, multi-homed Internet setups. In this talk, we first introduce the NorNet testbed as well as its deployment status. After that, we present some research results of the ongoing research at the Simula Research Laboratory on multi-path transport with Multi-Path TCP (MPTCP). Particularly, it will also show how the NorNet testbed can be utilized for research at the New York University (NYU) as well.
URL: https://www.simula.no/file/simulasimula2728pdf/download
MD5: 5d1741a4f975c75f90314627e8d516fd
Gran, Ernst Gunnar; Dreibholz, Thomas and Kvalbein, Amund: ``NorNet Core – A Multi-Homed Research Testbed´´ (PDF, 1458 KiB, 🇬🇧), in Computer Networks, Special Issue on Future Internet Testbeds, vol. 61, pp. 75–87, DOI 10.1016/j.bjp.2013.12.035, ISSN 1389-1286, March 14, 2014, [BibTeX, XML].

Keywords: NorNet Core, Testbed, Multi-Homing, Routing, Transport, Applications
Abstract: Over the last decade, the Internet has grown at a tremendous speed in both size and complexity. Nowadays, a large number of important services – for instance e-commerce, healthcare and many others – depend on the availability of the underlying network. Clearly, service interruptions due to network problems may have a severe impact. On the long way towards the Future Internet, the complexity will grow even further. Therefore, new ideas and concepts must be evaluated thoroughly, and particularly in realistic, real-world Internet scenarios, before they can be deployed for production networks. For this purpose, various testbeds – for instance PlanetLab, GpENI or G-Lab – have been established and are intensively used for research. However, all of these testbeds lack the support for so-called multi-homing. Multi-homing denotes the connection of a site to multiple Internet service providers, in order to achieve redundancy. Clearly, with the need for network availability, there is a steadily growing demand for multi-homing. The idea of the NorNet Core project is to establish a Future Internet research testbed with multi-homed sites, in order to allow researchers to perform experiments with multi-homed systems. Particular use cases for this testbed include realistic experiments in the areas of multi-path routing, load balancing, multi-path transport protocols, overlay networks and network resilience. In this paper, we introduce the NorNet Core testbed as well as its architecture.
URL: https://www.simula.no/file/simulasimula2236pdf/download
MD5: 2a2237f3e955ca8fb1b768b8a30ba7fe
Dreibholz, Thomas: ``On the Applicability of Reliable Server Pooling for Virtualised Network Function Resource Pooling´´ (PDF, 2476 KiB, 🇬🇧), in Proceedings of the 89th IETF Meeting, London/United Kingdom, March 4, 2014, [BibTeX, XML].

URL: https://www.simula.no/file/simulasimula2584pdf/download
MD5: b4cdac71c0a7fd2bf7888649956eeeae
Dreibholz, Thomas: ``The Status of MPTCP Deployment and Evaluation in the NorNet Testbed´´ (PDF, 1514 KiB, 🇬🇧), in Proceedings of the 89th IETF Meeting, London/United Kingdom, March 3, 2014, [BibTeX, XML].

URL: https://www.simula.no/file/simulasimula2582pdf/download
MD5: 79b1f59c28309d376f05b7ac3709ca9d
Dreibholz, Thomas: ``NorNet – An Open, Large-Scale Testbed for Multi-Homed Systems´´ (PDF, 4655 KiB, 🇬🇧), Invited Talk at Swinburne University, Centre for Advanced Internet Architectures (CAIA), Melbourne, Victoria/Australia, January 30, 2014, [BibTeX, XML].

Keywords: NorNet, NorNet Core, NorNet Edge, Testbed, Multi-Homing, Introduction, Status
Abstract: Multi-homing denotes the simultaneous connection of endpoints (e.g. cloud servers, smartphones, etc.) to multiple Internet Service Providers (ISP). That is, the endpoints remain reachable even when some of the ISPs have problems (e.g. malfunction of hardware or break of cables). Besides the redundancy aspect, multi-homing can also make load sharing by multi-path transport possible, i.e. increasing the application throughput by utilising multiple paths simultaneously. Multi-path transport can e.g. be realised by Concurrent Multi-Path Transfer for SCTP (CMT-SCTP) and Multi-Path TCP (MPTCP), two protocols that are currently under standardisation in the IETF. The growing need for and deployment of multi-homed applications makes large-scale testing and evaluation in realistic Internet setups necessary. For instance, different paths can have very different characteristics with regard to bandwidth, packet loss rate, congestion, delay and jitter. Therefore, the NorNet project of the Simula Research Laboratory is building up an open platform for such experiments: the NorNet testbed. It provides programmable nodes with multiple ISP connections – wired as well as wireless – that are distributed all over Norway as well as some international locations. This talk will give an overview over NorNet with a focus on its usage for research on multi-path transport. Particularly, it will also show how the NorNet testbed can be utilised for research at CAIA/Swinburne University.
URL: https://www.simula.no/file/caia2014-presentation-webpdf/download
MD5: 2c2282e72cc039210aa3b8ee97b389a6

2013

Dreibholz, Thomas: ``The NorNet Core Testbed – An Experiment Tutorial´´ (PDF, 4454 KiB, 🇬🇧), in Proceedings of the 1st International NorNet Users Workshop (NNUW-1), Fornebu, Akershus/Norway, September 19, 2013, [BibTeX, XML].

Abstract: This tutorial provides an introduction on how to get access to the NorNet Core testbed as well as how to run experiments in the testbed.
URL: https://www.simula.no/file/simulasimula2130pdf/download
MD5: f67a3e0e340f676c96c4486cf5308000
Dreibholz, Thomas: ``The NorNet Core Testbed – Introduction and Status´´ (PDF, 8399 KiB, 🇬🇧), in Proceedings of the 1st International NorNet Users Workshop (NNUW-1), Fornebu, Akershus/Norway, September 18, 2013, [BibTeX, XML].

Keywords: NorNet, NorNet Core, Testbed, Multi-Homing, Multi-Path Transport, Introduction
URL: https://www.simula.no/file/simulasimula2124pdf/download
MD5: 5c700705b018d485706b49a66b9d1a0c
Dreibholz, Thomas: ``The NorNet Project – A Research Testbed for Multi-Path Transport´´ (PDF, 23650 KiB, 🇬🇧), Invited Talk at Technische Universität Berlin, Department of Telecommunication Networks, Berlin/Germany, August 1, 2013, [BibTeX, XML].

URL: https://www.simula.no/file/simulasimula2056pdf/download
MD5: 2bdae2c9c4ee1ac2671d3730497f0e99
Dreibholz, Thomas: ``The NorNet Testbed: A Platform for Evaluating Multi-Path Transport in the Real-World Internet´´ (PDF, 13341 KiB, 🇬🇧), in Proceedings of the 87th IETF Meeting, Berlin/Germany, July 30, 2013, [BibTeX, XML].

URL: https://www.ietf.org/proceedings/87/slides/slides-87-mptcp-4.pdf
MD5: 60e2a88f7784a2ad5e95af77b4eac809
Dreibholz, Thomas and Ferlin, Simone: ``The NorNet Research Testbed´´ (PDF, 12015 KiB, 🇬🇧), Talk, in Proceedings of the CHANGE Bootcamp Workshop, Louvain-la-Neuve/Belgium, July 17, 2013, [BibTeX, XML].

URL: https://www.simula.no/file/simulasimula2046pdf/download
MD5: d6ee4ec1a6e0f3b30afbe4ac8e24aeac
Becke, Martin; Dreibholz, Thomas; Bayer, Andreas; Packeiser, Markus and Rathgeb, Erwin Paul: ``Alternative Transmission Strategies for Multipath Transport of Multimedia Streams over Wireless Networks´´ (PDF, 792 KiB, 🇬🇧), in Proceedings of the 12th IEEE International Conference on Telecommunications (ConTEL), pp. 147–153, ISBN 978-953-184-175-7, Zagreb, Središnja Hrvatska/Croatia, June 26, 2013, [BibTeX, XML].

Keywords: Multi-Path Transfer, Multimedia Transport, Scheduling Strategies, Real-Time, Wireless
Abstract: With the strongly growing popularity of mobile devices like smartphones and tablet computers, the number of end-systems with more than one network access – like UMTS/LTE and WLAN – is also increasing. This so-called multi-homing also leads to the desire of utilising multiple network paths simultaneously, in order to improve application payload throughput. Clearly, this so-called multi-path transfer feature is also very useful for the transport of multimedia contents, particularly when a single network access alone is not fast enough to fulfil the bandwidth requirements of the application. In many cases, multimedia transport is also sensitive for delays and packet losses. However, the focus of the current multi-path transfer approaches has been on bandwidth only. In order to tackle this challenge, our paper introduces two new send strategies to map payload data to different wireless paths. Finally, by using measurements, we show that a significant performance improvement for delay and loss-sensitive applications can be achieved in comparison to the existing approaches.
URL: https://www.simula.no/file/simulasimula2000pdf/download
MD5: b6125ad32798a84b2be4a349000fc1c3
Dreibholz, Thomas: ``An Overview of the NorNet Testbed for Multi-Homed Systems´´ (PDF, 21755 KiB, 🇬🇧), Invited Talk at Høgskolen i Oslo og Akershus (HiOA), Oslo/Norway, April 18, 2013, [BibTeX, XML].

URL: https://www.simula.no/file/simulasimula1984pdf/download
MD5: f3351ae0edda4c0e4f2efe0bdf8c4ada
Dreibholz, Thomas: ``The NorNet Project – An Introduction to NorNet for the Site Deployment at NTNU Trondheim´´ (PDF, 21705 KiB, 🇬🇧), Invited Talk at Norges teknisk-naturvitenskapelige universitet (NTNU), Trondheim, Sør-Trøndelag/Norway, April 12, 2013, [BibTeX, XML].

URL: https://www.simula.no/file/simulasimula1974pdf/download
MD5: b1c9b13724c18bee7f0d2db3fdee7243
Dreibholz, Thomas: ``The NorNet Project: A Research Platform for Robust and Secure Networks´´ (PDF, 7304 KiB, 🇬🇧), in Proceedings of the Essener Workshop zur Netzsicherheit (EWNS), Essen, Nordrhein-Westfalen/Germany, April 8, 2013, [BibTeX, XML].

Keywords: NorNet, Testbed, Multi-Homing, Setup, Research
Abstract: This talk gives an overview of the NorNet project, the new Internet testbed for multi-homed systems, and its research objectives.
URL: https://www.simula.no/file/simulasimula1968pdf/download
MD5: 3855ef4890e243dd180cc9f8abd745f6
Dreibholz, Thomas and Gran, Ernst Gunnar: ``Design and Implementation of the NorNet Core Research Testbed for Multi-Homed Systems´´ (PDF, 20082 KiB, 🇬🇧), in Proceedings of the 3nd International Workshop on Protocols and Applications with Multi-Homing Support (PAMS), pp. 1094–1100, DOI 10.1109/WAINA.2013.71, ISBN 978-0-7695-4952-1, Barcelona, Catalonia/Spain, March 27, 2013, [BibTeX, XML].

Keywords: NorNet, Testbed, Multi-Homing, Design, Implementation
Abstract: The Internet has made it possible to communicate and to use services over large geographical distances. While it has originally been built for less critical services like e-mail and file transfer, it is nowadays also increasingly often used for availability-critical services like e.g. e-commerce or healthcare. Clearly, the reachability of such services must be ensured by so-called multi-homing of endpoints. That is, endpoints are simultaneously connected to multiple Internet Service Providers (ISP) to provide redundancy. If one ISP has problems, it is intended that the connection to another one still works. However, such assumptions have never been verified in real, large-scale setups. The intention of the NorNet project is to build up a realistic Internet testbed for multi-homing. In this paper, we describe the design of NorNet with focus on the implementation of its fixed-line part: NorNet Core. This paper is intended to give researchers an overview of its mode of operation, its capabilities as well as its interesting feature realisations. The knowledge about these items is very useful to plan own experiments in the NorNet testbed.
URL: https://www.simula.no/file/threfereedinproceedingsreference2012-12-207643198512pdf/download
MD5: 6560234f120c9c1e0166928b1c13e400
Dreibholz, Thomas: ``An Introduction to NorNet for the Site Deployment at Høgskolen i Narvik´´ (PDF, 21440 KiB, 🇬🇧), Invited Talk at Høgskolen i Narvik (HiN), Narvik, Nordland/Norway, March 12, 2013, [BibTeX, XML].

URL: https://www.simula.no/file/simulasimula1950pdf/download
MD5: cd9f90c43fe2be66e12153d9bf38e460
Dreibholz, Thomas: ``An Overview of NorNet Core´´ (PDF, 19045 KiB, 🇬🇧), Invited Talk at the Geilo Siminar of the Simula Research Laboratory, Network Systems Group, Geilo, Buskerud/Norway, March 9, 2013, [BibTeX, XML].

URL: https://www.simula.no/file/simulasimula1948pdf/download
MD5: f18d7d4adda2c7dde085570f60b56d49

2012

Dreibholz, Thomas: ``An Introduction to NorNet Core for the Site Deployment at Universitetet i Stavanger´´ (PDF, 21576 KiB, 🇬🇧), Invited Talk at Universitetet i Stavanger (UiS), Stavanger, Rogaland/Norway, November 27, 2012, [BibTeX, XML].

Abstract: This invited talk at Universitetet i Stavanger gives an overview of the NorNet project, with particular focus on NorNet Core. It has been presented as part of the NorNet Core deployment visit.
URL: https://www.simula.no/file/simulasimula1626pdf/download
MD5: d53c0d9ac7012586e3f4accba4b61ab7
Dreibholz, Thomas: ``The NorNet Project – A Research Testbed for Multi-Homed Systems´´ (PDF, 37415 KiB, 🇬🇧), Invited Talk at Karlstads Universitet, Karlstad, Värmland/Sweden, November 2, 2012, [BibTeX, XML].

URL: https://www.simula.no/file/simulasimula1580pdf/download
MD5: 7763b43963c32f78d4c99873855556ec
Becke, Martin; Dreibholz, Thomas; Adhari, Hakim and Rathgeb, Erwin Paul: ``On the Fairness of Transport Protocols in a Multi-Path Environment´´ (PDF, 1970 KiB, 🇬🇧), in Proceedings of the IEEE International Conference on Communications (ICC), pp. 2666–2672, DOI 10.1109/ICC.2012.6363695, ISBN 978-1-4577-2052-9, Ottawa, Ontario/Canada, June 12, 2012, [BibTeX, XML].

Keywords: Multi-Homing, Multi-Path Transfer, Fairness, Congestion Control, Future Internet
Abstract: Today, a steadily growing number of devices contains multiple network interfaces. For example, nearly all smartphones are equipped with at least W-LAN as well as 3G/4G interfaces. In consequence, there is a rising demand for so-called multi-path transfer, which utilizes all of these interfaces simultaneously in order to maximize the payload throughput of applications. Currently, this so-called multi-path transfer is very actively discussed by the IETF, in form of the Multi-Path TCP (MPTCP) extension for TCP as well as the Concurrent Multi-path Transfer extension for SCTP (CMT-SCTP). Their larger-scale deployment in the Internet is expected for the near future. A key issue that prevents the standardization of these approaches is the fairness to concurrent TCP flows. A multi-path transfer should behave "TCP-friendly", i.e. cause no harm to the performance of the very widely deployed TCP-based applications. In this paper, we first extend the notion of "fairness" from single-path transport to multi-path transport. Furthermore, we introduce the relevant congestion control approaches in the IETF context for single-path as well as multi-path transfer. We simulatively analyze these approaches in a couple of interesting network configuration scenarios, in order to show their behavior with special regard to the fairness definitions. Particularly, we also point out items of further discussion which are the result of the current approaches.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/SCTP/Paper/ICC2012.pdf
MD5: 88ea6b1a3bfc82f23629900ac4a9f6b7
Becke, Martin; Dreibholz, Thomas; Adhari, Hakim and Rathgeb, Erwin Paul: ``A Future Internet Architecture supporting Multipath Communication Networks´´ (PDF, 743 KiB, 🇬🇧), in Proceedings of the 13th IEEE/IFIP Network Operations and Management Symposium (NOMS), pp. 639–642, DOI 10.1109/NOMS.2012.6211975, ISBN 978-1-4673-0268-5, Maui, Hawaii/U.S.A., April 19, 2012, [BibTeX, XML].

Keywords: Future Internet, Multipath Communications, Encapsulated Responsibility-Centric Architecture Model (ERiCA), Responsibilities, Decision Domains
Abstract: The classic layered OSI reference model has reached its limits for the Internet of today. In this paper, we propose a clean-slate conceptual design of a new architecture as a contribution to the ongoing discussion on the Future Internet. We address the shortcomings of the layered model by redesigning the classical model. Our approach differs from the concepts found in prior work, which focus on special parts of the problems (such as the application, the service or the event) by staggering back a couple of steps and trying to see the requirements from a different perspective. Our concept – which is denoted as Encapsulated Responsibility-Centric Architecture Model (ERiCA) – focuses on determining the responsibilities by using different planes in addition to a partitioning of the network into different decision domains. With this partitioning, we can reduce the complexity of providing a certain service.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/SCTP/Paper/NOMS2012.pdf
MD5: 0d471bef76ec8ae66b71f28e254deb82
Dreibholz, Thomas; Adhari, Hakim; Becke, Martin and Rathgeb, Erwin Paul: ``Simulation and Experimental Evaluation of Multipath Congestion Control Strategies´´ (PDF, 403 KiB, 🇬🇧), in Proceedings of the 2nd International Workshop on Protocols and Applications with Multi-Homing Support (PAMS), DOI 10.1109/WAINA.2012.186, ISBN 978-0-7695-4652-0, Fukuoka/Japan, March 29, 2012, [BibTeX, XML].

Keywords: Multipath Transfer, Congestion Control, Performance Analysis, Simulation, Measurement
Abstract: The need for service resilience is leading to a steadily growing number of multi-homed Internet sites. In consequence, this results in a growing demand for utilising multiple Internet accesses simultaneously, in order to improve application payload throughput during normal operation. Multi-path Transport Layer protocol extensions – like Multi-Path TCP (MPTCP) for TCP and Concurrent Multipath Transfer for SCTP (CMT-SCTP) – allow applications to make use of such network topologies. However, since TCP – which constitutes the basis of most Internet applications – and its congestion control procedures have been designed under the assumption of single-homed sites, fairness issues may arise by the usage of multipath transport. These issues are addressed by advanced congestion control approaches, which have already been examined by simulations. However, real-life network measurements are missing. In this paper, we perform an experimental proof-of-concept evaluation of several multipath congestion control strategies, which are currently under discussion within the IETF in the context of MPTCP as well as CMT-SCTP. Particularly, we validate effects that have been observed in simulations, in order to trigger further discussions on multipath congestion control. Also, our goal is to provide insight into the different approaches to support the ongoing IETF standardisation activities on multipath transport protocols.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/SCTP/Paper/PAMS2012.pdf
MD5: 9f0ed4e466615996b4e65ccb10ec3c7d
Adhari, Hakim; Becke, Martin and Dreibholz, Thomas: ``On the Fairness of Transport Protocols in a Multi-Path Environment´´ (PDF, 1004 KiB, 🇬🇧), in Proceedings of the 83rd IETF Meeting, Paris/France, March 27, 2012, [BibTeX, XML].

URL: https://www.ietf.org/proceedings/83/slides/slides-83-iccrg-3.pdf
MD5: 1345b92fb66655adf2b3c9c9827e2068
Dreibholz, Thomas: ``Evaluation and Optimisation of Multi-Path Transport using the Stream Control Transmission Protocol´´ (PDF, 36779 KiB, 🇬🇧), Habilitation Treatise, University of Duisburg-Essen, Faculty of Economics, Institute for Computer Science and Business Information Systems, URN urn:nbn:de:hbz:464-20120315-103208-1, March 13, 2012, [BibTeX, XML].

Keywords: Stream Control Transmission Protocol (SCTP), Multi-Path Transport, Dissimilar Paths, Fairness, Evaluation, Optimisation
Abstract: The Stream Control Transmission Protocol (SCTP) as defined in RFC 4960 is an advanced Transport Layer protocol that provides support for multi-homing. That is, SCTP endpoints may simultaneously use multiple Network Layer addresses, which allows to connect the endpoints to multiple networks for redundancy purposes. However, for the transfer of user data, only one of the possible paths is currently used at a time. All other paths remain as backup and are only used for retransmissions. Clearly, the existence of multiple paths has led to the idea of applying load sharing among the paths. An extension to SCTP – denoted as Concurrent Multipath Transfer (CMT) – realises this load sharing functionality. While this approach works well for similar paths, i.e. paths having similar characteristics regarding bandwidths, bit error rates and delays, the use of dissimilar paths does not work that neatly. In this thesis, the issues of dissimilar paths for CMT-based load sharing will be demonstrated first. The reasons for these issues will be identified and solutions proposed. These solutions will be evaluated in simulations, as well as partially also in a real-world Internet testbed setup, in order to show their effectiveness. In particular, it will be shown that a combination of multiple mechanisms is necessary to make CMT work as expected under a wide range of network and system parameters. Furthermore, the fairness of CMT-based transport – in concurrency to classic non-CMT flows – will be analysed. The usage of plain CMT leads to an overly aggressive bandwidth occupation on so-called shared bottlenecks. As a countermeasure, the idea of Resource Pooling will be utilised. For this purpose, two new and one adapted congestion control approach – all based on the Resource Pooling principle – will be introduced and examined in similar as well as dissimilar path setups, in order to show how to fairly deploy CMT transport in the Internet. The results of this work have also been contributed to the ongoing IETF standardisation process of SCTP and its extensions.
URL: https://duepublico2.uni-due.de/servlets/MCRFileNodeServlet/duepublico_derivate_00029737/Dre2012_final.pdf
MD5: add34f0b780cb35b7ee1f963ea85e59c
Dreibholz, Thomas: ``Konzepte für das Future Internet aus der Netzperspektive´´ (PDF, 5777 KiB, 🇩🇪), Habilitation Talk, University of Duisburg-Essen, Faculty of Economics, Institute for Computer Science and Business Information Systems, URN urn:nbn:de:hbz:464-20120404-135350-0, March 13, 2012, [BibTeX, XML].

Keywords: Future Internet, Habilitationsvortrag
Abstract: Vielen seiner Benutzer erscheint das Internet als neuartig und hochmodern. Seine Grundlagen jedoch sind keineswegs neu, sondern basieren auf mittlerweile fast 40 Jahre alten Ideen. Dienste werden mittels eines geschichteten, hierarchischen Protokollstacks realisiert, bei welchem eine Interaktion nicht-benachbarter Schichten nicht vorgesehen ist. Dieser starre Aufbau macht bereits das Anpassen der Internet-Architektur an die Anforderungen der heutigen Anwendungen – wie etwa File Sharing, Videotelefonie und mobile Endgeräte – kompliziert. Die großen Herausforderungen des zukünftigen Internets – welches als das Future Internet bezeichnet wird – mit Anwendungsszenarien wie Cloud Computing, Internet of Things, Sensornetzwerken und vielen weiteren – erfordern jedoch noch weitaus umfangreichere Anpassungen. Zudem ist eine große Flexibilität erforderlich, um auch weiteren – heute noch nicht absehbaren – Anforderungen gerecht zu werden. Im Rahmen dieses Habilitationsvortrages wird zunächst kurz auf die Probleme des aktuellen Internets eingegangen sowie die Herausforderungen des Future Internets vorgestellt. Im Anschluss daran wird eine Auswahl der für den Übergang zum Future Internet möglichen evolutionären sowie revolutionären Ansätze vorgestellt. Der Schwerpunkt liegt hierbei auf den noch relativ neuen – und in der Forschung momentan sehr aktiv diskutierten – revolutionären Ansätzen, welche mit der Idee des sogenannten Clean Slate einen vollständigen Neuansatz anstreben. Hierbei werden die Ansätze der Funktionalen Komposition, des Content-Centric Networking sowie der Virtualisierung von Netzwerken vorgestellt. Zum Schluss wird dann auf die Frage eingegangen, wie eine Nutzung der vorgestellten Ansätze in der Praxis möglich ist und welche der aktuell in Diskussion befindlichen Ansätze sich in Zukunft voraussichtlich durchsetzen werden.
URL: https://duepublico2.uni-due.de/servlets/MCRFileNodeServlet/duepublico_derivate_00029756/Habilitationsvortrag.pdf
MD5: bd09fd9172fccb9edd4ee88299038f47
Dreibholz, Thomas; Adhari, Hakim; Becke, Martin and Rathgeb, Erwin Paul: ``NetPerfMeter – A Versatile Tool for Multi-Protocol Network Performance Evaluations´´ (PDF, 334 KiB, 🇬🇧), OMNeT++ Code Contribution, University of Duisburg-Essen, Institute for Experimental Mathematics, February 8, 2012, [BibTeX, XML].

Keywords: Application Model, NetPerfMeter, Performance Evaluation, Multipath Transfer
Abstract: Transport Layer protocols supporting multipath transfer, i.e. to simultaneously utilise multiple Network Layer paths, are actively discussed in the IETF – particularly in the context of Multi-Path TCP (MPTCP) and Concurrent Multipath Transfer for SCTP (CMT-SCTP). Congestion control for such protocols is an important research topic. In this code contribution paper, we introduce our application model NetPerfMeter. NetPerfMeter has been developed for performance evaluations of different transport protocols, like for the Linux/FreeBSD performance metering application NetPerfMeter.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/SCTP/Paper/NetPerfMeterSim2012.pdf
MD5: dc5a70671636b3367df1a2878f6081fd
Dreibholz, Thomas; Becke, Martin; Adhari, Hakim; Rathgeb, Erwin Paul; Rüngeler, Irene; Seggelmann, Robin and Tüxen, Michael: ``Improvements to the SCTP Environment in the INET Framework´´ (PDF, 875 KiB, 🇬🇧), OMNeT++ Code Contribution, University of Duisburg-Essen, Institute for Experimental Mathematics, February 6, 2012, [BibTeX, XML].

Keywords: Stream Control Transmission Protocol (SCTP), SCTP Extensions, Simulation, Multi-Homing, Auto-Routing
Abstract: This code contribution paper provides an overview of the enhancements to the Stream Control Transmission Protocol (SCTP) environment of the INET Framework. Besides a highly improved SCTP core protocol, a couple of SCTP extensions – being either already standardized or currently under discussion in the IETF – have been realized. Furthermore, extended test applications and an auto-routing module with multi-homing support have been added. These enhancements make state-of-the-art SCTP simulation scenarios possible.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/SCTP/Paper/SCTPSim2012.pdf
MD5: ae78a4d0bda04dc875c7262cd285434c
Dreibholz, Thomas; Becke, Martin; Adhari, Hakim and Rathgeb, Erwin Paul: ``RspSim – A Simulation Model of the Reliable Server Pooling Framework´´ (PDF, 226 KiB, 🇬🇧), OMNeT++ Code Contribution, University of Duisburg-Essen, Institute for Experimental Mathematics, February 6, 2012, [BibTeX, XML].

Keywords: Reliable Server Pooling, Simulation, Evaluation, Model, Cloud Computing
Abstract: This code contribution paper provides an overview of the RSPSIM model, which is a simulation model for the Reliable Server Pooling (RSerPool) framework. RSerPool denotes an IETF standard for the management of server pools and sessions with these pools. Such mechanisms are also crucial in the context of cloud computing research.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/RspSim2012.pdf
MD5: d515de6b0f138484c8e7709af8293735

2011

Dreibholz, Thomas: ``Multipath-Transfer mit dem Stream Control Transmission Protocol´´ (PDF, 2096 KiB, 🇬🇧), Invited Talk at Technische Universität Darmstadt, Multimedia Communications Lab, Darmstadt, Hessen/Germany, November 16, 2011, [BibTeX, XML].

URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/SCTP/Paper/Darmstadt2011.pdf
MD5: 438d0b3f6caab7b168c16a24eba97306
Dreibholz, Thomas; Becke, Martin; Adhari, Hakim and Rathgeb, Erwin Paul: ``Evaluation of A New Multipath Congestion Control Scheme using the NetPerfMeter Tool-Chain´´ (PDF, 360 KiB, 🇬🇧), in Proceedings of the 19th IEEE International Conference on Software, Telecommunications and Computer Networks (SoftCOM), pp. 1–6, ISBN 978-953-290-027-9, Hvar, Dalmacija/Croatia, September 16, 2011, [BibTeX, XML].

Keywords: NetPerfMeter Tool-Chain, Concurrent Multipath Transfer, Congestion Control, Dissimilar Paths, Performance Analysis
Abstract: Multi-homed Internet sites become more and more widespread, due to the rising dispersal of inexpensive Internet access technologies combined with the growing deployment of resilience-critical applications. Concurrent Multipath Transfer (CMT) denotes the Transport Layer approach to utilise multiple network paths simultaneously, in order to improve application payload throughput. Currently, CMT is a quite hot topic in the IETF – in form of the Multipath TCP (MPTCP) and CMT-SCTP protocol extensions for TCP and SCTP. However, an important issue is still not fully solved: multipath congestion control. In order to support the IETF activities, we have set up a distributed Internet testbed for CMT evaluation. An important tool – which we have developed for multi-protocol Transport Layer performance analysis – is the Open Source NetPerfMeter tool-chain. It supports the parametrisation and processing of measurement runs as well as results collection, post-processing and plotting. However, its key feature is to support multiple Transport Layer protocols, which makes a quantitative comparison of different protocols – including state-of-the-art features like CMT – possible. In this paper, we first introduce NetPerfMeter and then show a proof-of-concept performance evaluation of CMT congestion controls which are currently discussed in the IETF standardisation process of CMT-SCTP.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/SCTP/Paper/SoftCOM2011.pdf
MD5: 23b808c6caa72f0cfb5213d8b6cf7b31
Dreibholz, Thomas; Becke, Martin; Adhari, Hakim and Rathgeb, Erwin Paul: ``On the Impact of Congestion Control for Concurrent Multipath Transfer on the Transport Layer´´ (PDF, 6498 KiB, 🇬🇧), in Proceedings of the 11th IEEE International Conference on Telecommunications (ConTEL), pp. 397–404, ISBN 978-953-184-152-8, Graz, Steiermark/Austria, June 16, 2011, [BibTeX, XML].

Keywords: Concurrent Multipath Transfer, Congestion Control, Resource Sharing, Dissimilar Paths, Performance Analysis
Abstract: Due to the resilience requirements of a steadily growing number of critical Internet services (like emergency call handling or e-commerce transactions), the deployment of multi-homed network sites becomes more and more common. Having multiple Internet access paths, it seems straightforward to utilise them simultaneously in order to improve payload throughput by so-called Concurrent Multipath Transfer (CMT). Currently, CMT extensions for the two important Internet Transport Layer protocols – Multipath-TCP (MPTCP) for TCP and CMT-SCTP for SCTP – are in the focus of IETF standardisation. A challenge – which is currently very actively discussed in the IETF context – is congestion control for these CMT protocols. Based on the idea of Resource Pooling (RP), two approaches are currently discussed in the IETF: our own approach CMT/RP for CMT-SCTP as well as the MPTCP congestion control for MPTCP. Both approaches only have been roughly tested yet – mostly in similar path setups, i.e. paths having almost the same QoS characteristics, using "their" protocol. Therefore, the goal of this paper is to compare the existing approaches. Particularly, we also analyse more challenging scenarios containing dissimilar paths, i.e. paths having differing characteristics. Our goal is to provide insight into the different approaches, to support the IETF standardisation activities on CMT.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/SCTP/Paper/ConTEL2011.pdf
MD5: aaf983738968d60f58a9abafc54d4344
Dreibholz, Thomas: ``Server-Redundanz und Lastverteilung einfach in eigene Anwendungen integrieren – mit Reliable Server Pooling und RSPLIB´´ (PDF, 1309 KiB, 🇩🇪), in Proceedings of the LinuxTag, Berlin/Germany, May 12, 2011, [BibTeX, XML].

Keywords: Reliable Server Pooling (RSerPool), Hochverfügbarkeit, Redundanz, Überblick, Implementierung, RSPLIB
Abstract: RSPLIB ist die Open-Source-Implementierung von Reliable Server Pooling (RSerPool), dem noch sehr neuen IETF-Standard für Server-Redundanz und Sitzungsverwaltung. Dieser Artikel soll insbesondere zeigen, wie RSerPool mit RSPLIB in eigenen Anwendungen für Hochverfügbarkeit und Lastverteilung eingesetzt werden kann. Im Rahmen des Vortrags soll zudem eine Beispielanwendung in der Praxis demonstriert werden.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/LinuxTag2011.pdf
MD5: 7a76c18c786514b2dea9ca272ecc7bbc
Dreibholz, Thomas; Rüngeler, Irene; Seggelmann, Robin; Tüxen, Michael; Rathgeb, Erwin Paul and Stewart, Randall R.: ``Stream Control Transmission Protocol: Past, Current, and Future Standardization Activities´´ (PDF, 287 KiB, 🇬🇧), in IEEE Communications Magazine, vol. 49, no. 4, pp. 82–88, DOI 10.1109/MCOM.2011.5741151, ISSN 0163-6804, April 5, 2011, [BibTeX, XML].

Abstract: The Stream Control Transmission Protocol (SCTP) is a general-purpose transport layer protocol providing a service similar to TCP – plus a set of advanced features to utilize the enhanced capabilities of modern IP networks and to support increased application requirements. Nowadays, there are SCTP implementations for all major operating systems. While SCTP was standardized as an RFC several years ago, there is still significant ongoing work within the IETF to discuss and standardize further features in the form of protocol extensions. In this article, we first introduce the SCTP base protocol and already standardized extensions. After that, we focus on the ongoing SCTP standardization progress in the IETF and give an overview of activities and challenges in the areas of security and concurrent multipath transport.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/SCTP/Paper/CommMag2011.pdf
MD5: 51c1a62c2f4dfeb2725b1e0fae3b3d10
Adhari, Hakim; Dreibholz, Thomas; Becke, Martin; Rathgeb, Erwin Paul and Tüxen, Michael: ``Evaluation of Concurrent Multipath Transfer over Dissimilar Paths´´ (PDF, 666 KiB, 🇬🇧), in Proceedings of the 1st International Workshop on Protocols and Applications with Multi-Homing Support (PAMS), pp. 708–714, DOI 10.1109/WAINA.2011.92, ISBN 978-0-7695-4338-3, Singapore, March 22, 2011, [BibTeX, XML].

Keywords: Concurrent Multipath Transfer, Dissimilar Paths, Buffer Handling, Performance Analysis, Experimental Validation
Abstract: The steadily growing deployment of resilience-critical Internet services is leading to an increasing number of Multi-Homed network sites. Asymmetric Digital Subscriber Lines (ADSL) are an inexpensive way to add a secondary Internet access connection. With the development of Multi-Path Transport Layer protocols – like Multipath TCP (MPTCP) and the Stream Control Transmission Protocol (SCTP) furnished by a Concurrent Multipath Transfer (CMT-SCTP) extension – there is also a strong interest in utilising all access connections simultaneously to improve the data throughput of the applications. However, combining network paths over ADSL with paths over other access technologies like fibre optic links implies highly dissimilar paths with significantly different bandwidths, delays and queuing behaviours. Efficient Multi-Path transport over such dissimilar paths is a challenging task for the new Transport Layer protocols under development. In this paper, we show the difficulties of Multi-Path transport in a real-world dissimilar path setup which consists of a high-speed fibre optic link and an ADSL connection. After that, we present an optimised buffer handling technique which solves the transport efficiency issues in this setup. Our optimisation is first analysed by simulations. Finally, we also show the usefulness of our approach by experimental evaluation in a real Multi-Homed Internet setup.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/SCTP/Paper/PAMS2011.pdf
MD5: a19f952606b97dc19de3870e7af038ca
Becke, Martin and Dreibholz, Thomas: ``Multi-Path Transport´´ (PDF, 1660 KiB, 🇬🇧), in Proceedings of the 1st DFG/NSF Doctoral Consortium, San Juan/Puerto Rico, Poster Presentation, March 13, 2011, [BibTeX, XML].

URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/SCTP/Paper/GENIWorkshop2011.pdf
MD5: 7ddf90624d681ac2fd4da0882e5780cc
Becke, Martin; Dreibholz, Thomas; Rathgeb, Erwin Paul and Formann, Johannes: ``Link Emulation on the Data Link Layer in a Linux-based Future Internet Testbed Environment´´ (PDF, 465 KiB, 🇬🇧), in Proceedings of the 10th International Conference on Networks (ICN), pp. 92–98, ISBN 978-1-61208-002-4, St. Maarten/Netherlands Antilles, January 25, 2011, [BibTeX, XML].

Keywords: Link Emulation, Data Link Layer, Future Internet Testbed, NetEm, Dummynet
Abstract: Protocol design and development is not a straight-forward process. Each approach must be validated for interactions and side-effects in the existing network environments. But the Internet itself is not a good test environment, since its components are not controllable and certain problem situations (like congestion or error conditions) are difficult to reproduce. Various testbeds have been built up to fill this gap. Most of these testbeds also support link emulation, i.e. using software to mimic the characteristic behaviour of certain kinds of network links (like bandwidth bottlenecks or error-prone radio transmissions). The most popular link emulation systems are the Linux-based NetEm and Dummynet, which are e.g. applied on the IP layer of Planet-Lab and various other testbeds. However, the restriction to the OSI Network Layer (here: IP) is insufficient to test new non-IP Future Internet protocols. In this paper, we first introduce Dummynet and NetEm. After that, we will present our approach of adapting Dummynet for Linux to support link emulation on the Data Link Layer. Finally, we evaluate the applicability and performance of Dummynet and NetEm for link emulation on the Data Link Layer, in a Planet-Lab-based testbed environment. Our goal is to outline the performance and limitations of both approaches in the context of Planet-Lab-based testbeds, in order to make them applicable for the evaluation of non-IP Future Internet protocols.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/SCTP/Paper/ICN2011.pdf
MD5: 7dc2f73a942b21aaf8993354ead8f9e2

2010

Dreibholz, Thomas; Zhou, Xing; Becke, Martin; Pulinthanath, Jobin; Rathgeb, Erwin Paul and Du, Wencai: ``On the Security of Reliable Server Pooling Systems´´ (PDF, 540 KiB, 🇬🇧), in International Journal on Intelligent Information and Database Systems (IJIIDS), vol. 4, no. 6, pp. 552–578, DOI 10.1504/IJIIDS.2010.036894, ISSN 1751-5858, December 2010, [BibTeX, XML].

Keywords: Reliable Server Pooling (RSerPool), Security, Attacks, Robustness, Performance Analysis, PlanetLab
Abstract: In order to cope with the requirements of availability-critical Internet services, Reliable Server Pooling (RSerPool) has been developed as the new IETF standard for a lightweight server redundancy and session failover framework. While the service and pool management performance of RSerPool had already been the topic of various research papers, its security has not yet been widely examined. But security for availability-critical systems is crucial, since service outages – regardless of whether being caused by system failures or intentional Denial of Service (DoS) attacks – are not acceptable for the users of such systems. In this article, we first introduce RSerPool as well as the underlying SCTP protocol. In an analysis of the attack threats, we will show the possibilities of an attacker to degrade the service provided by an RSerPool system. We will furthermore introduce possible countermeasures, in order to prevent attacks and improve the robustness of the systems. We will finally show the effectiveness of our proposed countermeasures using simulations. In order to validate our simulation results, we furthermore compare them to measurements from a real-world Internet setup using the PlanetLab.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/IJIIDS2010.pdf
MD5: 53f11ab53ddfed318568f99ab08ba5aa
Dreibholz, Thomas and Becke, Martin: ``The RSPLIB Project – From Research to Application´´ (PDF, 2105 KiB, 🇬🇧), Demo Presentation at the IEEE Global Communications Conference (GLOBECOM), Miami, Florida/U.S.A., December 8, 2010, [BibTeX, XML].

Keywords: Reliable Server Pooling (RSerPool), RSPLIB, Service Availability, Session Failover, Load Distribution, Demonstration
Abstract: The goal of the RSPLIB project has been to design and develop an Open Source implementation of Reliable Server Pooling (RSerPool), the new IETF framework for server pool and session management. While its original intention had been the research on RSerPool optimizations and protocol improvements, it has meanwhile become a production-ready platform which is already used by a couple of applications. In our proposed demo for the IEEE GLOBECOM 2010, we would like to introduce RSerPool and show how applications can benefit from using the features provided by RSPLIB.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/Globecom2010-Demo.pdf
MD5: 826a0e3f90f875bbae375509b6672d25
Dreibholz, Thomas; Becke, Martin; Rathgeb, Erwin Paul and Tüxen, Michael: ``On the Use of Concurrent Multipath Transfer over Asymmetric Paths´´ (PDF, 1036 KiB, 🇬🇧), in Proceedings of the IEEE Global Communications Conference (GLOBECOM), DOI 10.1109/GLOCOM.2010.5683579, ISBN 978-1-4244-5637-6, Miami, Florida/U.S.A., December 7, 2010, [BibTeX, XML].

Keywords: Concurrent Multipath Transfer, Resource Pooling, Asymmetric Paths, Buffer Handling, Performance Analysis
Abstract: With the deployment of more and more resilience-critical Internet applications, there is a rising demand for multi-homed network sites. This leads to the desire for simultaneously utilising all available access paths to improve application data throughput. This is commonly known as Concurrent Multipath Transfer (CMT), approaches for several Transport Layer protocols have been proposed. Combined with Resource Pooling (RP), CMT can also fairly coexist with concurrent non-CMT flows. Current approaches focus on symmetric paths (i.e. similar bandwidth, delay and error rate). However, asymmetric paths are much more likely – particularly for realistic Internet setups – and efficient CMT usage on such paths is therefore crucial. In this paper, we first show the challenges of plain as well as RP-aware CMT data transport over asymmetric paths. After that, we introduce mechanisms for efficient transport over such paths. Finally, we analyse the performance of our approaches by using simulations.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/SCTP/Paper/Globecom2010.pdf
MD5: 96629a6c95f6882e9fdd54acdee2de5d
Dreibholz, Thomas; Seggelmann, Robin; Tüxen, Michael and Rathgeb, Erwin Paul: ``Transmission Scheduling Optimizations for Concurrent Multipath Transfer´´ (PDF, 633 KiB, 🇬🇧), in Proceedings of the 8th International Workshop on Protocols for Future, Large-Scale and Diverse Network Transports (PFLDNeT), vol. 8, ISSN 2074-5168, Lancaster, Pennsylvania/U.S.A., November 29, 2010, [BibTeX, XML].

Keywords: Concurrent Multipath Transfer, Scheduling, Optimizations, Analysis
Abstract: SCTP is a general-purpose Transport Layer protocol with out-of-the-box support for multi-streaming as well as multi-homing. A protocol extension, which is denoted as CMT-SCTP, extends SCTP by supporting Concurrent Multipath Transfer (CMT). That is, multiple network paths are utilized simultaneously in order to improve the payload data throughput. However, dissimilar paths – i.e. paths having different delays or bandwidths – are challenging and also very likely in internet setups. In this paper, we show how CMT-SCTP data transport performance can be improved by combining multi-streaming with an advanced stream scheduling policy and SCTP API enhancements. The performance benefit of our approach in dissimilar path setups is proven by simulations.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/SCTP/Paper/PFLDNeT2010.pdf
MD5: 18c2a0c4862d943aa53ff719459d7203
Dreibholz, Thomas: ``Buffer Splitting for Efficient Transport over Asymmetric Paths´´ (PDF, 363 KiB, 🇬🇧), Talk at the SIG Multipath Meeting during the 10th Joint EuroFGI and ITG Workshop on Visions of Future Network Generations (EuroView), Würzburg, Bayern/Germany, August 4, 2010, [BibTeX, XML].

URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/SCTP/Paper/EuroView2010-SIGMultiPath-SCTP.pdf
MD5: af684a42671409244ea97fa6518935f9
Dreibholz, Thomas; Becke, Martin; Henke, Christian and Rathgeb, Erwin Paul: ``An Approach for Transferring an End-to-End Transport Service into a Functional Building Block Structure´´ (PDF, 149 KiB, 🇬🇧), in Proceedings of the 5th GI/ITG KuVS Workshop on the Future Internet, Stuttgart, Baden-Württemberg/Germany, June 9, 2010, [BibTeX, XML].

Keywords: Transport, Multi-Path, Functional Building Blocks, Cross-Layer Optimization, Future Internet
Abstract: Current network stacks based on the classic OSI layered reference model are restricted and inflexible, which makes the addition and deployment of new features difficult. Operating systems offer an interface for the Transport Layer functionalities to applications. The usage of this interface is very widespread, making it useful to maintain this interface. However, the layered structure should be replaced. In this paper, we propose our approach for breaking up the functionalities of the OSI Transport Layer into the concept so called functional building blocks. Each functional building block provides a particular service, which – in interaction with the other functional building blocks – is able to provide a service similar to the classic OSI Transport Layer. The concept allows for easy removal, replacement or addition of existing and new functional building blocks to adapt the service to state-of-the-art and future requirements, particularly including multi-path transport and QoS.
URL: https://web.archive.org/web/20171101093204/http://www.future-internet.org/files/2010/Folien/Abstract_Dreibholz2.pdf
MD5: e39b36008b54d24b3dfb391ac8b3eeb5
Zhou, Xing; Dreibholz, Thomas; Becke, Martin; Pulinthanath, Jobin; Rathgeb, Erwin Paul and Du, Wencai: ``The Software Modeling and Implementation of Reliable Server Pooling and RSPLIB´´ (PDF, 2764 KiB, 🇬🇧), in Proceedings of the 8th ACIS Conference on Software Engineering Research, Management and Applications (SERA), pp. 129–136, DOI 10.1109/SERA.2010.26, ISBN 978-0-7695-4075-7, Montréal, Québec/Canada, May 24, 2010, [BibTeX, XML].

Keywords: Reliable Server Pooling (RSerPool), RSPLIB, Service Availability, Software Modeling, Implementation
Abstract: With the growing complexity of software applications, there is an increasing demand for solutions to distribute workload into server pools. Grid Computing provides powerful – but also highly complex – mechanisms to realize such tasks. Also, there is a steadily growing number of downtime-critical applications, requiring redundant servers to ensure service availability in case of component failures. To cope with the demand for server redundancy and service availability, the IETF has recently standardized the lightweight Reliable Server Pooling (RSerPool) framework, which is a common architecture for server pool and session management. In this paper, we first introduce the concept of RSerPool and then present the modeling thoughts of RSPLIB and the underlying general groupware design. Based on RSPLIB, we will illustratively show how to easily develop applications on top of RSerPool. We will also offer an application evaluation example for a proof-of-concept setup to distribute ray-tracing computation workload into a compute pool.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/SERA2010.pdf
MD5: 889ce62f9c2de4ebe431b604d07a3f30
Dreibholz, Thomas; Becke, Martin; Pulinthanath, Jobin and Rathgeb, Erwin Paul: ``Applying TCP-Friendly Congestion Control to Concurrent Multipath Transfer´´ (PDF, 957 KiB, 🇬🇧), in Proceedings of the 24th IEEE International Conference on Advanced Information Networking and Applications (AINA), pp. 312–319, DOI 10.1109/AINA.2010.117, ISBN 978-0-7695-4018-4, Perth, Western Australia/Australia, April 21, 2010, [BibTeX, XML].

Keywords: Multi-Homing, Congestion Control, Resource Pooling, Fairness, Proof of Concept
Abstract: The steadily growing importance of Internet-based applications and their resilience requirements lead to a rising number of multi-homed sites. The idea of Concurrent Multipath Transfer (CMT) is to exploit the existence of multiple paths among endpoints to increase application data throughput. However, handling the congestion control of each path independently lacks of fairness against non-CMT flows. In this paper, we describe our approach of combining CMT with the idea of Resource Pooling (RP) in order to achieve a performance improvement over non-CMT transfer while still remaining fair to concurrent flows on congested links. Unlike existing approaches which adapt classic TCP to a multi-homed CMT protocol, our approach does not depend on specific characteristics of TCP. Instead, we base on already entrenched functional blocks of CMT transfer, on the example of the CMT-enabled SCTP (Stream Control Transmission Protocol). In a simulative proof-of-concept analysis, we show that our approach – while relatively simple – is already quite effective.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/SCTP/Paper/AINA2010.pdf
MD5: 11d400faa0a4c994d27fa6a6ebc5f9cc
Biella, Daniel; Huth, Dieter; Striewe, Michael; Kohnen, Michael; Dreibholz, Thomas and Becke, Martin: ``Erfahrungsbericht: Zur Organisation und Implementierung PC-gestützter Prüfungen an der Universität Duisburg-Essen´´ (PDF, 1375 KiB, 🇩🇪), in E-Teaching.org, March 25, 2010, [BibTeX, XML].

Keywords: L-PLUS, E-Assessment
Abstract: Dieser Artikel beschreibt die technischen, organisatorischen und inhaltlichen Herausforderungen, die bei der Organisation und Implementierung einer Plattform für PC-gestützte Prüfungen an der Universität Duisburg-Essen zu bewältigen waren. Anhand zweier Szenarien aus dem Wintersemester 2009/10 wird der Umstieg von papiergestützten Prüfungen auf PC-gestützte Prüfungen sowie die Möglichkeit der Prüfung komplexer Aufgabenstellungen beispielhaft erläutert.
URL: https://www.e-teaching.org/praxis/erfahrungsberichte/10-03-25_PC-Hall_Biella-Huth-Striewe-Kohnen-Dreibholz-Becke.pdf
MD5: 52856bad6dd8ce266a244a56ed9272e2
Reschka, Thomas; Dreibholz, Thomas; Becke, Martin; Pulinthanath, Jobin and Rathgeb, Erwin Paul: ``Enhancement of the TCP Module in the OMNeT++/INET Framework´´ (PDF, 582 KiB, 🇬🇧), in Proceedings of the 3rd ACM/ICST International Workshop on OMNeT++, ISBN 978-963-9799-87-5, Torremolinos, Málaga/Spain, March 19, 2010, [BibTeX, XML].

Keywords: OMNeT++, INET Framework, TCP, Selective Acknowledgement, Flow Control
Abstract: The INET framework for the simulation tool OMNeT++ provides a TCP module, which can be used for evaluating various Internet applications. However, the implementation of this TCP module has not been state of the art. Some important features of modern TCP implementations – particularly Selective Acknowledgements (SACK) and a complete Flow Control – have been missing. In this paper, we first introduce basic TCP mechanisms. After that, we introduce the extensions we have made to the TCP module of INET. Finally, we show some results of our performance evaluation.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/SCTP/Paper/OMNeT__Workshop2010-TCP.pdf
MD5: 53c126fdf4f77d433ef5f7601dea5b60
Dreibholz, Thomas; Becke, Martin; Pulinthanath, Jobin and Rathgeb, Erwin Paul: ``Implementation and Evaluation of Concurrent Multipath Transfer for SCTP in the INET Framework´´ (PDF, 587 KiB, 🇬🇧), in Proceedings of the 3rd ACM/ICST International Workshop on OMNeT++, DOI 10.4108/ICST.SIMUTOOLS2010.8673, ISBN 978-963-9799-87-5, Torremolinos, Málaga/Spain, March 19, 2010, [BibTeX, XML].

Keywords: INET Framework, SCTP, Concurrent Multipath Transfer, Model, Evaluation
Abstract: The steadily growing importance of resilience-critical Internet applications leads to a rising number of multi-homed sites and systems. But since the protocols of the classical Internet – particularly TCP – assume a single access path only, the number of programs supporting multiple network paths is still small. The Stream Control Transport Protocol (SCTP), which is an advanced general-purpose transport protocol and the possible successor of TCP, brings the support of multi-homing into the applications. For technical reasons, SCTP uses one network path for data transmission and utilizes the other paths for backup only. An extension to support the load balancing of user data onto multiple paths in order to increase the payload throughput is Concurrent Multipath Transfer for SCTP, denoted as CMT-SCTP. In this paper, we describe our CMT-SCTP extension for the SCTP model provided by the INET framework. By using proof-of-concept simulations, we furthermore demonstrate its usability and configuration parameters.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/SCTP/Paper/OMNeT__Workshop2010-SCTP.pdf
MD5: 910129c4f8742f16aa603347276bcf90

2009

Dreibholz, Thomas; Zhou, Xing; Rathgeb, Erwin Paul and Du, Wencai: ``A PlanetLab-Based Performance Analysis of RSerPool Security Mechanisms´´ (PDF, 721 KiB, 🇬🇧), in Proceedings of the 10th IEEE International Conference on Telecommunications (ConTEL), pp. 213–220, ISBN 978-953-184-131-3, Zagreb, Središnja Hrvatska/Croatia, June 8, 2009, [BibTeX, XML].

Keywords: Reliable Server Pooling (RSerPool), Security, Attacks, Denial of Service, Robustness, Performance Analysis
Abstract: Reliable Server Pooling (RSerPool) denotes the new IETF standard for a lightweight server redundancy and session failover framework for availability-critical applications. A number of research papers have already addressed the service and pool management performance of RSerPool in general. However, the important topic of security, including the system robustness against intentional attacks, has not yet been intensively addressed. In particular, none of the proposed Denial of Service (DoS) attack countermeasure mechanisms has been evaluated in a real-world Internet setup. For that reason, this paper provides an analysis of the robustness of RSerPool systems against DoS attacks. We will outline the DoS attack bandwidth which is necessary for a significant service degradation. Furthermore, we will present simple but effective DoS attack countermeasure mechanisms to significantly reduce the impact of attacks. Our analysis is based on a real-world Internet setup using the PlanetLab. We will furthermore compare the performance measurements against simulation results.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/ConTEL2009.pdf
MD5: 490dda7191b7b3dae11d61785131040d
Dreibholz, Thomas and Rathgeb, Erwin Paul: ``Overview and Evaluation of the Server Redundancy and Session Failover Mechanisms in the Reliable Server Pooling Framework´´ (PDF, 1157 KiB, 🇬🇧), in International Journal on Advances in Internet Technology (IJAIT), vol. 2, no. 1, pp. 1–14, ISSN 1942-2652, June 8, 2009, [BibTeX, XML].

Keywords: Reliable Server Pooling (RSerPool), Service Availability, Redundancy, Session Failover, Server Selection
Abstract: The number of availability-critical Internet applications is steadily increasing. To support the development and operation of such applications, the IETF has recently defined a new standard for a common server redundancy and session failover framework: Reliable Server Pooling (RSerPool). The basic ideas of the RSerPool framework are not entirely new, but their combination into a single, resource-efficient and unified architecture is. Service availability achieved by the redundancy of servers directly leads to the issues of load distribution and load balancing, which are both important for the performance of RSerPool systems. Therefore, it is crucial to evaluate the performance of such systems with respect to the load balancing strategy required by the service application. In this article – which is an extended version of our paper [1] – we first present an overview of the RSerPool architecture with a focus on the component failure detection and handling mechanisms. We will also shortly introduce the underlying SCTP protocol and its link redundancy features. After that, we will present a quantitative, application-independent performance analysis of the failure detection and session failover mechanisms provided by RSerPool, with respect to important adaptive and non-adaptive load balancing strategies.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/IJAIT2009.pdf
MD5: d3f66675bd31433a0b788a0cbac7121c
Zhou, Xing; Dreibholz, Thomas; Rathgeb, Erwin Paul and Du, Wencai: ``Takeover Suggestion – A Registrar Redundancy Handling Optimization for Reliable Server Pooling Systems´´ (PDF, 543 KiB, 🇬🇧), in Proceedings of the 10th IEEE/ACIS International Conference on Software Engineering, Artificial Intelligence, Networking and Parallel/Distributed Computing (SNPD), pp. 168–173, DOI 10.1109/SNPD.2009.17, ISBN 978-3-642-01202-0, Daegu/South Korea, May 27, 2009, [BibTeX, XML].

Keywords: Reliable Server Pooling (RSerPool), Redundancy, Handlespace Management, Takeover, Performance Analysis
Abstract: Reliable Server Pooling (RSerPool) is the IETF's new standard for a common server redundancy and session failover framework to support availability-critical applications. Server pools are maintained by redundant management components denoted as registrars. These registrars monitor the availability of servers in the pool and remove them in case of failure. Furthermore, they synchronize their view of the pool with other registrars to provide information redundancy. In this paper, we first illustrate the implications of registrar redundancy on the performance of RSerPool systems. After that, we present an optimization approach for the server pool management, which improves the management performance in case of registrar problems like hardware failures or Denial of Service attacks. The performance of our approach is evaluated in real life using PlanetLab measurements.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/SNPD2009.pdf
MD5: a9bb30606285c619fb63bfacbd78939a
Zhou, Xing; Dreibholz, Thomas; Fu, Fa; Du, Wencai and Rathgeb, Erwin Paul: ``Evaluation and Optimization of the Registrar Redundancy Handling in Reliable Server Pooling Systems´´ (PDF, 484 KiB, 🇬🇧), in Proceedings of the IEEE 23rd International Conference on Advanced Information Networking and Applications (AINA), pp. 256–262, DOI 10.1109/AINA.2009.25, ISBN 978-0-7695-3638-5, Bradford, West Yorkshire/United Kingdom, May 26, 2009, [BibTeX, XML].

Keywords: Reliable Server Pooling (RSerPool), Redundancy, Takeover, Handlespace Management, Performance Analysis
Abstract: The Reliable Server Pooling (RSerPool) architecture is the IETF's new standard for a lightweight server redundancy and session failover framework to support availability-critical applications. RSerPool combines the ideas from different research areas into a single, resource-efficient and unified architecture. Server pools are maintained by redundant management components, which are called registrars. Registrars monitor the availability of servers in the pool and remove them in case of failure. Furthermore, they synchronize their view of the pool with other registrars to provide information redundancy. In this paper, we first analyse the implications of registrar redundancy on the server pool performance. Furthermore, we present an optimization approach for the server pool management, which improves the system performance in case of registrar problems by hardware failures or Denial of Service attacks.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/AINA2009.pdf
MD5: 85883bf586a6c76481c7a3adbd0f20d6
Zhu, Wenyu; Dreibholz, Thomas; Rathgeb, Erwin Paul and Zhou, Xing: ``A Scalable QoS Device for Broadband Access to Multimedia Services´´ (PDF, 1081 KiB, 🇬🇧), in SERSC International Journal of Multimedia and Ubiquitous Engineering (IJMUE), vol. 4, no. 2, pp. 157–172, ISSN 1975-0080, April 30, 2009, [BibTeX, XML].

Keywords: Quality of Service (QoS), Broadband Internet, Flow Routing, Multimedia, Intelligent Packet Discard
Abstract: Nowadays, an increasing number of users gets high-speed broadband access to the Internet. These broadband connections make new multimedia applications possible. However, such applications also introduce new Quality of Service (QoS) requirements to the network. Particularly, they require an assured bandwidth even in the case of network overload. The network itself has to provide such bandwidth assurances. This article introduces our concept of a novel network QoS device being located in network edge nodes. It provides a solution for relaxed QoS guarantees to certain flows on a congested link by focussing packet discard on selected flows. However, unlike for IntServ solutions like RSVP, our approach only requires minimal signalling and therefore provides both efficiency and scalability. We furthermore provide a quantitative performance evaluation of our QoS device by using simulations.
URL: https://gvpress.com/journals/IJMUE/vol4_no2/14.pdf
MD5: 3a8837e5ef699ddff971bcdfbf98b84b
Dreibholz, Thomas and Mulik, Jaiwant: ``Reliable Server Pooling MIB Module Definition´´ (TXT, 84 KiB, 🇬🇧), RFC 5525, IETF, DOI 10.17487/RFC5525, ISSN 2070-1721, April 22, 2009, [BibTeX, XML].

Abstract: Reliable Server Pooling (RSerPool) is a framework to provide reliable server pooling. The RSerPool framework consists of two protocols: ASAP (Aggregate Server Access Protocol) and ENRP (Endpoint Handlespace Redundancy Protocol). This document defines an SMIv2-compliant (Structure of Management Information Version 2) Management Information Base (MIB) module providing access to managed objects in an RSerPool implementation. This memo defines an Experimental Protocol for the Internet community.
URL: https://www.ietf.org/rfc/rfc5525.txt
MD5: 0a97f3889ba2b726d4e738e9c4c77ee6
Dreibholz, Thomas; Zhou, Xing and Rathgeb, Erwin Paul: ``SimProcTC – The Design and Realization of a Powerful Tool-Chain for OMNeT++ Simulations´´ (PDF, 552 KiB, 🇬🇧), in Proceedings of the 2nd ACM/ICST International Workshop on OMNeT++, pp. 1–8, DOI 10.4108/ICST.SIMUTOOLS2009.5517, ISBN 978-963-9799-45-5, Rome/Italy, March 6, 2009, [BibTeX, XML].

Keywords: SimProcTC, Simulation, Parametrization, Run Distribution, Results Visualization
Abstract: In this paper, we introduce our Open Source simulation tool-chain for OMNeT++ simulations: SimProcTC. This model-independent tool-chain has been designed to perform the common and frequently recurring tasks of simulation work – which are the parametrization of runs, the distributed run processing and the results visualization – in an efficient and easy to use manner. It is already successfully deployed for several OMNeT++-based research projects.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/OMNeT__Workshop2009.pdf
MD5: 1ec4aec2824e6f4d11f1e1af9a8d3991
Zhou, Xing; Dreibholz, Thomas; Du, Wencai and Rathgeb, Erwin Paul: ``Evaluation of Attack Countermeasures to Improve the DoS Robustness of RSerPool Systems by Simulations and Measurements´´ (PDF, 471 KiB, 🇬🇧), in Proceedings of the 16. ITG/GI Fachtagung Kommunikation in Verteilten Systemen (KiVS), Informatik aktuell, pp. 217–228, Springer, DOI 10.1007/978-3-540-92666-5_18, ISBN 978-3-540-92665-8, Kassel, Hessen/Germany, March 5, 2009, [BibTeX, XML].

Keywords: Reliable Server Pooling (RSerPool), Security, Attacks, Denial of Service, Robustness, Performance Analysis
Abstract: The Reliable Server Pooling (RSerPool) architecture is the IETF's new standard for a lightweight server redundancy and session failover framework to support availability-critical applications. RSerPool combines the ideas from different research areas into a single, resource-efficient and unified architecture. While there have already been a number of research papers on its performance in general, the robustness against intentional attacks has not been intensively addressed yet. In particular, there have not been any analyses for real setups. Therefore, the goal of this paper is to provide a robustness analysis in order to outline the attack bandwidth which is necessary for a significant impact on RSerPool-based services. This analysis is based on lab measurements – using a real RSerPool system setup – as well as on measurements for comparison and validation. Furthermore, we present and evaluate countermeasure approaches to significantly reduce the impact of attacks.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/KiVS2009.pdf
MD5: 75e82d6388aaef304f99eba50e33f69f

2008

Zhu, Wenyu; Dreibholz, Thomas; Rathgeb, Erwin Paul and Zhou, Xing: ``A Scalable QoS Device for Broadband Access to Multimedia Services´´ (PDF, 509 KiB, 🇬🇧), in Proceedings of the IEEE International Conference on Future Generation Communication and Networking (FGCN), vol. 1, pp. 343–348, DOI 10.1109/FGCN.2008.124, ISBN 978-0-7695-3431-2, Sanya, Hainan/People's Republic of China, December 13, 2008, [BibTeX, XML].

Keywords: Quality of Service (QoS), Broadband Internet, Flow Routing, Multimedia, Intelligent Packet Discard
Abstract: This paper presents the performance evaluation of a novel network device being located in network edge nodes. It provides a solution for relaxed QoS guarantees to certain flows on a congested link by focussing packet discard on selected flows. However, unlike IntServ solutions – e.g. RSVP – our approach only requires minimal signalling and therefore provides both efficiency and scalability. In this paper, we first describe the ideas of our QoS device and then provide a simulative performance analysis for different multimedia flow scenarios.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/FlowRouting/Paper/FGCN2008.pdf
MD5: 4aeb2680d2d15cb85f53961ff16c707c
Dreibholz, Thomas and Rathgeb, Erwin Paul: ``Towards the Future Internet – An Overview of Challenges and Solutions in Research and Standardization´´ (PDF, 1643 KiB, 🇬🇧), in Proceedings of the 2nd GI/ITG KuVS Workshop on the Future Internet, Karlsruhe, Baden-Württemberg/Germany, November 11, 2008, [BibTeX, XML].

Keywords: Reliable Server Pooling (RSerPool), Stream Control Transmission Protocol (SCTP), IPv6, Future Internet
Abstract: The basic intention for the development of the Internet has been the simple and inexpensive interconnection of nodes to provide services like file download or e-mail. However, due to its huge growth and popularity, the classical protocols – which still constitute the basis of today's Internet – have reached their limits of scalability and functionality. Lots of research has been performed in order to overcome these restrictions. In our presentation, we would like to give a survey of the challenges on Network, Transport, Session and Application Layer, as well as an outline of solutions which will constitute – from the current perspective in 2008 and with regard to the standardization progress of the IETF – the basis of the Internet in the year 2020.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/FutureInternet2008.pdf
MD5: 087b79294d286a6ad2ac31b62a86f8a9
Schöttle, Pascal; Dreibholz, Thomas and Rathgeb, Erwin Paul: ``On the Application of Anomaly Detection in Reliable Server Pooling Systems for Improved Robustness against Denial of Service Attacks´´ (PDF, 563 KiB, 🇬🇧), in Proceedings of the 33rd IEEE Conference on Local Computer Networks (LCN), pp. 207–214, DOI 10.1109/LCN.2008.4664171, ISBN 978-1-4244-2413-9, Montréal, Québec/Canada, October 16, 2008, [BibTeX, XML].

Keywords: Reliable Server Pooling (RSerPool), Anomaly Detection, Attacks, Robustness, Denial of Service
Abstract: The Reliable Server Pooling (RSerPool) architecture is the IETF's upcoming standard of a light-weight server redundancy and session failover framework for availability-critical applications. RSerPool combines the ideas from different research areas into a single, resource-efficient and unified architecture. Although there have already been a number of research papers on the pool management, load distribution and failover handling performance of RSerPool, the robustness against intentional attacks has not been intensively addressed yet. Therefore, the first goal of this paper is to provide a robustness analysis in order to outline the attack bandwidth necessary for a significant impact on RSerPool-based services. After that, we present our anomaly detection approach that has been designed to protect RSerPool systems against attacks. We also show the effectiveness of this approach by simulations.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/LCN2008.pdf
MD5: 8a883302aadb660fba4af49c65573c12
Zhu, Wenyu; Dreibholz, Thomas and Rathgeb, Erwin Paul: ``Analysis and Evaluation of a Scalable QoS Device for Broadband Access to Multimedia Services´´ (PDF, 166 KiB, 🇬🇧), in Proceedings of the 33rd IEEE Conference on Local Computer Networks (LCN), pp. 504–505, DOI 10.1109/LCN.2008.4664212, ISBN 978-1-4244-2413-9, Montréal, Québec/Canada, October 15, 2008, [BibTeX, XML].

Keywords: Quality of Service (QoS), Broadband Internet, Flow Routing, Multimedia, Intelligent Packet Discard
Abstract: This paper presents the initial evaluation of a novel network device being located in edge nodes. It provides relaxed QoS guarantees to certain flows on a congested link by focussing packet discard on selected flows. In contrast to classical IntServ solutions, our approach requires minimal signalling and therefore provides both efficiency and scalability. In this paper, we first describe the ideas of our QoS device and then provide first results of our ongoing simulative performance evaluation and optimization.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/FlowRouting/Paper/LCN2008-FlowRouting.pdf
MD5: 4b24ce40f15989ca57ccb44bdbdf4d82
Lei, Peter; Ong, Lyndon; Tüxen, Michael and Dreibholz, Thomas: ``An Overview of Reliable Server Pooling Protocols´´ (TXT, 33 KiB, 🇬🇧), Informational RFC 5351, IETF, DOI 10.17487/RFC5351, ISSN 2070-1721, September 30, 2008, [BibTeX, XML].

Abstract: The Reliable Server Pooling effort (abbreviated "RSerPool") provides an application-independent set of services and protocols for building fault-tolerant and highly available client/server applications. This document provides an overview of the protocols and mechanisms in the Reliable Server Pooling suite. This memo provides information for the Internet community.
URL: https://www.ietf.org/rfc/rfc5351.txt
MD5: ef2740924a7fd7e776672161b88ab7fa
Dreibholz, Thomas and Tüxen, Michael: ``Reliable Server Pooling Policies´´ (TXT, 33 KiB, 🇬🇧), RFC 5356, IETF, DOI 10.17487/RFC5356, ISSN 2070-1721, September 30, 2008, [BibTeX, XML].

Abstract: This document describes server pool policies for Reliable Server Pooling (RSerPool) including considerations for implementing them at Endpoint Handlespace Redundancy Protocol (ENRP) servers and pool users. This memo defines an Experimental Protocol for the Internet community.
URL: https://www.ietf.org/rfc/rfc5356.txt
MD5: b3865e8c10685a43bd16cc90ecf4df29
Dreibholz, Thomas and Zhou, Xing: ``SCTP and RSerPool: Architectures and Protocols for the Future Internet´´ (PDF, 2256 KiB, 🇬🇧), Invited Talk at Hainan University, College of Information Science and Technology (CIST), Haikou, Hainan/People's Republic of China, September 26, 2008, [BibTeX, XML].

URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/Haikou2008-English.pdf
MD5: ff7675477fc736d4f43908249ea7861b
Dreibholz, Thomas; Rathgeb, Erwin Paul and Zhou, Xing: ``On Robustness and Countermeasures of Reliable Server Pooling Systems against Denial of Service Attacks´´ (PDF, 479 KiB, 🇬🇧), in Proceedings of the 7th International IFIP Networking Conference, Lecture Notes in Computer Science, vol. 4982, pp. 586–598, Springer, DOI 10.1007/978-3-540-79549-0_51, ISBN 978-3-540-79548-3, Singapore, May 7, 2008, [BibTeX, XML].

Keywords: Reliable Server Pooling, Attacks, Denial of Service, Robustness, Countermeasures
Abstract: The Reliable Server Pooling (RSerPool) architecture is the IETF's novel approach to standardize a light-weight protocol framework for server redundancy and session failover. It combines ideas from different research areas into a single, resource-efficient and unified architecture. While there have already been a number of contributions on the performance of RSerPool for its main tasks – pool management, load distribution and failover handling – the robustness of the protocol framework has not yet been evaluated against intentional attacks. The first goal of this paper is to provide a robustness analysis. In particular, we would like to outline the attack bandwidth necessary for a significant impact on the service. Furthermore, we present and evaluate our countermeasure approach to significantly reduce the impact of attacks.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/Networking2008.pdf
MD5: 185b4404904fcb988d4c237634f2c1aa
Dreibholz, Thomas and Rathgeb, Erwin Paul: ``An Evaluation of the Pool Maintenance Overhead in Reliable Server Pooling Systems´´ (PDF, 3289 KiB, 🇬🇧), in SERSC International Journal on Hybrid Information Technology (IJHIT), vol. 1, no. 2, pp. 17–32, ISSN 1738-9968, April 2008, [BibTeX, XML].

Keywords: Reliable Server Pooling (RSerPool), Server Pools, Handlespace Management, Stream Control Transmission Protocol (SCTP), Performance, Measurements
Abstract: Currently, the IETF RSerPool WG is standardizing a generic protocol framework for server redundancy and session failover: Reliable Server Pooling (RSerPool). An important property of RSerPool is its lightweight architecture: server pool and session management can be realized with small CPU power and memory requirements. That is, RSerPool-based services can also be managed and provided by embedded systems. Up to now, there has already been some research on the performance of the data structures managing server pools. But a generic, application-independent performance analysis – in particular also including measurements in real system setups – is still missing. The aim of this article is therefore – after giving an outline of the RSerPool framework, an introduction to the pool management procedures and a description of our pool management approach – to first provide a detailed performance evaluation of the pool management structures themselves. Afterwards, the performance of a prototype implementation is analysed in order to evaluate its applicability in a real network setup.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/IJHIT2008.pdf
MD5: 175a230c33b66aa474020607da51b8c4
Dreibholz, Thomas and Rathgeb, Erwin Paul: ``A Powerful Tool-Chain for Setup, Distributed Processing, Analysis and Debugging of OMNeT++ Simulations´´ (PDF, 558 KiB, 🇬🇧), in Proceedings of the 1st ACM/ICST International Workshop on OMNeT++, DOI 10.4108/ICST.SIMUTOOLS2008.2990, ISBN 978-963-9799-20-2, Marseille, Bouches-du-Rhône/France, March 7, 2008, [BibTeX, XML].

Keywords: SimProcTC, Simulation Model, Parametrization, Simulation Run Distribution, Plotting, Analysis
Abstract: In this paper, we introduce our Open Source tool-chain providing the parametrization, distributed execution, results post-processing and debugging for OMNeT++-based simulations. While the initial motivation of these tools has been the support of our simulation model of the Reliable Server Pooling (RSerPool) framework, it has been particularly designed with model-independence in mind. That is, it can be easily adapted to other simulation models and therefore may be useful for other users of OMNeT++-based simulation models as well.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/OMNeTWorkshop2008.pdf
MD5: 23f563d708ab1eb3f55d6dd21ef4eee4
Zhou, Xing; Dreibholz, Thomas and Rathgeb, Erwin Paul: ``A New Server Selection Strategy for Reliable Server Pooling in Widely Distributed Environments´´ (PDF, 444 KiB, 🇬🇧), in Proceedings of the 2nd IEEE International Conference on Digital Society (ICDS), pp. 171–177, DOI 10.1109/ICDS.2008.12, ISBN 978-0-7695-3087-1, Sainte Luce/Martinique, February 14, 2008, [BibTeX, XML].

Keywords: Reliable Server Pooling (RSerPool), Load Balancing, Least-Used Selection, Latency
Abstract: In order to provide a generic, application-independent and resource-efficient framework for server redundancy and session failover, the IETF RSerPool WG is currently standardizing the Reliable Server Pooling (RSerPool) framework. Server redundancy has to take load distribution and load balancing into consideration since these issues are crucial for the system performance. There has already been some research on the server selection strategies of RSerPool for different application scenarios. In particular, it has been shown that the adaptive Least Used selection usually provides the best performance. This strategy requires up-to-date load information of the services, which has to be propagated among distributed pool management components. But network delay (which is realistic for systems being widely distributed to achieve availability in case of regional servers failures) as well as caching of information may both lead to obsolete load information. Therefore, the purpose of this paper is to analyse and evaluate the performance of a new server selection rule to cope with update latencies. Especially, we will also analyse the impact of different workload parameters on the performance of the new server selection strategy.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/ICDS2008-LUD.pdf
MD5: 8e1fe5960264a82415c27b389278d35c
Dreibholz, Thomas and Rathgeb, Erwin Paul: ``Reliable Server Pooling – A Novel IETF Architecture for Availability-Sensitive Services´´ (PDF, 504 KiB, 🇬🇧), in Proceedings of the 2nd IEEE International Conference on Digital Society (ICDS), pp. 150–156, DOI 10.1109/ICDS.2008.11, ISBN 978-0-7695-3087-1, Sainte Luce/Martinique, February 14, 2008, [BibTeX, XML]. Awarded with the Best Paper Award.

Keywords: Reliable Server Pooling (RSerPool), Availability, Redundancy, Failover, Server Selection
Abstract: Reliable Server Pooling (RSerPool) is a light-weight protocol framework for server redundancy and session failover, currently still under standardization by the IETF RSerPool WG. While the basic ideas of RSerPool are not new, their combination into a single, resource-efficient and unified architecture is. Server redundancy directly leads to the issues of load distribution and load balancing, which are both important for the performance of RSerPool systems. Therefore, it is crucial to evaluate the performance of such systems with respect to the load balancing strategy required by the application. The goal of our paper is – after presenting a short overview of the RSerPool architecture and its application cases – to provide a quantitative, application-independent performance analysis of RSerPool's server failure handling capabilities with respect to important adaptive and non-adaptive load balancing strategies. We will also analyse the impact of RSerPool protocol parameters on the performance of the server failure handling functionalities and the network overhead.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/ICDS2008-Failover.pdf
MD5: 2b0abbad0f9f40af03022525c2a8c184

2007

Zhou, Xing; Dreibholz, Thomas and Rathgeb, Erwin Paul: ``A New Approach of Performance Improvement for Server Selection in Reliable Server Pooling Systems´´ (PDF, 10141 KiB, 🇬🇧), in Proceedings of the 15th IEEE International Conference on Advanced Computing and Communication (ADCOM), pp. 117–121, DOI 10.1109/ADCOM.2007.19, ISBN 0-7695-3059-1, Guwahati/India, December 19, 2007, [BibTeX, XML].

Keywords: Reliable Server Pooling (RSerPool), Redundancy, Load Balancing, Performance Evaluation
Abstract: Reliable Server Pooling (RSerPool) is a light-weight protocol framework for server redundancy and session failover, currently still under standardization by the IETF RSerPool WG. While the basic ideas of RSerPool are not completely new, their combination into a single, resource-efficient and unified architecture is. Server redundancy directly leads to the issues of load distribution and load balancing, which are both important for the performance of RSerPool systems. While there has already been some research on the server selection policies of RSerPool, an interesting question still remains open: Is it possible to further improve the load balancing performance of certain policies by simply letting servers reject inappropriately scheduled requests? In this case, the failover handling mechanisms of RSerPool could choose a possibly better server instead. The purpose of this paper is, after presenting an outline of the RSerPool framework, to analyse and evaluate the performance of our new approach. In particular, we will also analyse the impact of RSerPool protocol parameters on the performance of the server selection functionalities as well as on the overhead.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/ADCOM2007.pdf
MD5: 8e50985edbad8e96e04a1066c7ccd780
Zhou, Xing; Dreibholz, Thomas and Rathgeb, Erwin Paul: ``Evaluation of a Simple Load Balancing Improvement for Reliable Server Pooling with Heterogeneous Server Pools´´ (PDF, 456 KiB, 🇬🇧), in Proceedings of the IEEE International Conference on Future Generation Communication and Networking (FGCN), vol. 1, pp. 173–180, DOI 10.1109/FGCN.2007.119, ISBN 0-7695-3048-6, Jeju Island/South Korea, December 8, 2007, [BibTeX, XML].

Keywords: Reliable Server Pooling (RSerPool), Redundancy, Load Balancing, Heterogeneous Pools, Performance Evaluation
Abstract: The IETF is currently standardizing a light-weight protocol framework for server redundancy and session failover: Reliable Server Pooling (RSerPool). It is the novel combination of ideas from different research areas into a single, resource-efficient and unified architecture. Server redundancy directly leads to the issues of load distribution and load balancing. Both are important and have to be considered for the performance of RSerPool systems. While there has already been some research on the server selection policies of RSerPool, an interesting question is still open: Is it possible to further improve the load balancing performance of the standard policies without modifying the policies – which are well-known and widely supported – themselves? Our approach places its focus on the session layer rather than the policies and simply lets servers reject inappropriately scheduled requests. Applying failover handling mechanisms of RSerPool, in this case, could choose a more appropriate server instead. In [26], we have already shown that our approach is useful for homogeneous server pools. But is it also useful for heterogeneous pools? In this paper, we first present a short outline of the RSerPool framework. Afterwards, we analyse and evaluate the performance of our new approach for different server capacity distributions. Especially, we are also going to analyse the impact of RSerPool protocol and system parameters on the performance of the server selection functionalities as well as on the overhead.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/FGCN2007-LoadBalancing.pdf
MD5: 6967acc9a600841ae38313c55605d36c
Dreibholz, Thomas and Rathgeb, Erwin Paul: ``An Evaluation of the Pool Maintenance Overhead in Reliable Server Pooling Systems´´ (PDF, 482 KiB, 🇬🇧), in Proceedings of the IEEE International Conference on Future Generation Communication and Networking (FGCN), vol. 1, pp. 136–143, DOI 10.1109/FGCN.2007.62, ISBN 0-7695-3048-6, Jeju Island/South Korea, December 6, 2007, [BibTeX, XML].

Keywords: Reliable Server Pooling (RSerPool), Server Pools, Handlespace Management, SCTP, Performance
Abstract: Reliable Server Pooling (RSerPool) is a protocol framework for server redundancy and session failover, currently still under standardization by the IETF RSerPool WG. An important property of RSerPool is its lightweight architecture: server pool and session management can be realized with small CPU power and memory requirements. That is, RSerPool-based services can also be managed and provided by embedded systems. Currently, there has already been some research on the performance of the data structures managing server pools. But a generic, application-independent performance analysis – in particular also including measurements in real system setups – is still missing. Therefore, the aim of this paper is – after an outline of the RSerPool framework, an introduction to the pool management procedures and a description of our pool management approach – to first provide a detailed performance evaluation of the pool management structures themselves. Afterwards, the performance of a prototype implementation is analysed in order to evaluate its applicability under real network conditions.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/FGCN2007-HsMgt.pdf
MD5: 3f06ad92c93f4dcde961912cfe251b11
Dreibholz, Thomas: ``An Introduction to Reliable Server Pooling and the RSPLIB Implementation´´ (PDF, 7736 KiB, 🇬🇧), Invited Talk at Hainan University, College of Information Science and Technology (CIST), Haikou, Hainan/People's Republic of China, December 2, 2007, [BibTeX, XML].

URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/HaikouTalk2007.pdf
MD5: bc192125b5728d9da4b0996a75d19f5e
Zhou, Xing; Dreibholz, Thomas and Rathgeb, Erwin Paul: ``Improving the Load Balancing Performance of Reliable Server Pooling in Heterogeneous Capacity Environments´´ (PDF, 408 KiB, 🇬🇧), in Proceedings of the 3rd Asian Internet Engineering Conference (AINTEC), Lecture Notes in Computer Science, vol. 4866, pp. 125–140, Springer, DOI 10.1007/978-3-540-76809-8_12, ISBN 978-3-540-76808-1, November 28, 2007, [BibTeX, XML].

Keywords: Reliable Server Pooling (RSerPool), Redundancy, Load Balancing, Heterogeneous Pools, Performance Evaluation
Abstract: The IETF is currently standardizing a light-weight protocol framework for server redundancy and session failover: Reliable Server Pooling (RSerPool). It is the novel combination of ideas from different research areas into a single, resource-efficient and unified architecture. Server redundancy directly leads to the issues of load distribution and load balancing. Both are important and have to be considered for the performance of RSerPool systems. While there has already been some research on the server selection policies of RSerPool, an interesting question is still open: Is it possible to further improve the load balancing performance of the standard policies without modifying the policies – which are well-known and widely supported – themselves? Our approach places its focus on the session layer rather than the policies and simply lets servers reject inappropriately scheduled requests. But is this approach useful – in particular if the server capacities increase in terms of a heterogeneous capacity distribution? Applying failover handling mechanisms of RSerPool, in this case, could choose a more appropriate server instead. In this paper, we first present a short outline of the RSerPool framework. Afterwards, we analyse and evaluate the performance of our new approach for different server capacity distributions. Especially, we are also going to analyse the impact of RSerPool protocol and system parameters on the performance of the server selection functionalities as well as on the overhead.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/AINTEC2007.pdf
MD5: a3252db5751ad15acf01794460125589
Dreibholz, Thomas: ``Hochverfügbarkeit mit Reliable Server Pooling´´ (PDF, 7740 KiB, 🇩🇪), in Proceedings of the Linuxtage in Essen, Essen, Nordrhein-Westfalen/Germany, November 10, 2007, [BibTeX, XML].

Keywords: Reliable Server Pooling (RSerPool), Hochverfügbarkeit, Redundanz, Überblick, Implementierung, RSPLIB
Abstract: Mit der ständig wachsenden Verbreitung von Internetzugängen nimmt auch die Anzahl an verfügbarkeits-kritischen Diensten im Netz zu. Ausfälle von z.B. VoIP-Vermittlungsanlagen zur Weiterleitung von Notrufen oder e-Commerce-Anwendungen sind nicht akzeptabel. Zur Sicherstellung der Verfügbarkeit von Diensten bei Geräte- und Netzwerkausfällen müssen diese Komponenten redundant ausgelegt sein. Spezialisierte Redundanzlösungen – insbesondere z.B. für Web-Server – gibt es zwar viele, eine einheitliche, für viele Dienste nutzbare Lösung fehlte jedoch noch. Reliable Server Pooling, abgekürzt RSerPool, ist ein Rahmenwerk zur Bereitstellung hochverfügbarer Anwendungen durch redundante Server, es befindet sich zur Zeit in der Standardisierung durch die IETF RSerPool-Arbeitsgruppe. Im RSerPool-Konzept werden Server, welche den gleichen Dienst anbieten, zu einem Pool zusammengefaßt. Neben der Hauptaufgabe – der Verfügbarkeit von Diensten – ist insbesondere auch die Lastverteilung ein wichtiges Anwendungsgebiet von RSerPool. Im Rahmen eines Forschungsprojektes haben wir – die Arbeitsgruppe Technik der Rechnernetze am Institut für Experimentelle Mathematik der Universität Duisburg-Essen – im Jahre 2002 damit begonnen, einen plattformunabhängigen RSerPool-Prototypen als Open Source unter GPL-Lizenz zu entwickeln. Mittlerweile wird unser Projekt durch die Deutsche Forschungsgemeinschaft (DFG) gefördert. Unser System läuft zur Zeit unter Linux, FreeBSD, Darwin (MacOS X) und Solaris, wobei die Unterstützung für weitere Plattformen – insbesondere auch für Embedded-Systeme – geplant ist. Als einzige vollständige Implementierung des zukünftigen RSerPool-Standards sind wir Referenzimplementierung der IETF RSerPool-Arbeitsgruppe und wirken mit Tests und Forschungsarbeiten aktiv in der Standardisierung mit. In unserem Vortrag geben wir zunächst eine kurze Einführung zu RSerPool. Dabei wollen wir insbesondere auch die Merkmale verdeutlichen, die RSerPool von existierenden Lösungen – wie Linux Virtual Server (LVS) oder dem kommerziellen Cisco Distributed Director – unterscheiden. Außerdem wollen wir zeigen, welche speziellen Funktionalitäten RSerPool bietet um den Nutzen eines Serverpools sowohl für dessen Betreiber als auch für den Anwender zu optimieren: die Möglichkeit zur vollautomatischen Konfiguration von Komponenten und die Festlegung pool-spezifischer Serverauswahlregeln. Diese Funktionalitäten werden wir am Beispiel einer Anwendung von RSerPool für Real-Time Distributed Computing verdeutlichen. Im zweiten Teil unseres Vortrags werden wir auf unsere Open Source Implementierung rsplib eingehen. Neben dem Aufbau der einzelnen Komponenten werden wir insbesondere auch interessante Details der Implementierung vorstellen und beschreiben, wie wir auftretende Probleme erfolgreich lösen konnten. Insbesondere wollen wir dabei auch unsere gesammelten Erfahrungen beim Erstellen von auf unterschiedlichen Betriebssystemen (Linux, FreeBSD, MacOS X, Solaris) und Hardware (x86, x64, PPC) lauffähiger Software vorstellen. Im Anschluß daran zeigen wir, wie das RSerPool-API dazu genutzt werden kann, eigene Anwendungen hochverfügbar zu machen und die Möglichkeiten zur Lastverteilung im Pool verwendet werden können. Ein Schwerpunkt dieser Einführung wird dabei insbesondere die einfache und effiziente Realisierung des Failover-Mechanisms sein, d.h. des Verfahrens zur Wiederherstellung eines Sitzungszustandes auf einem neuen Server nach Ausfall des alten. Im Besonderen werden wir dabei zeigen, welche Fähigkeiten RSerPool und sein API mitbringen um dieses – teilweise recht komplexe Thema – in vielen Fällen übersichtlich und mit wenigen Zeilen Programmcode zu lösen: Hochverfügbarkeit für eigene Anwendungen muß nicht kompliziert sein! Zum Abschluß stellen wir noch unsere Beispielanwendung vor, ein System zum verteilten Berechnen von Fraktalgrafiken. Mit diesem System lassen sich die grundlegenden Eigenschaften von RSerPool – welche im Vortrag vorgestellt wurden – sehr anschaulich demonstrieren: die Verwaltung dynamischer Pools, Lastverteilung und Failover bei Serverausfall. Selbstverständlich werden wir unser Beispielsystem beim Vortrag auch in der Praxis demonstrieren, bei Vorhandensein eines Internetzugangs sogar mit einem Szenario aus weltweit verteilten Ressourcen.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/Linuxtage2007.pdf
MD5: 7882ef3b335f592778b19b6d3f3c0796
Dreibholz, Thomas; Zhou, Xing and Rathgeb, Erwin Paul: ``A Performance Evaluation of RSerPool Server Selection Policies in Varying Heterogeneous Capacity Scenarios´´ (PDF, 383 KiB, 🇬🇧), in Proceedings of the 33rd IEEE EuroMirco Conference on Software Engineering and Advanced Applications, pp. 157–164, DOI 10.1109/EUROMICRO.2007.9, ISBN 0-7695-2977-1, Lübeck, Schleswig-Holstein/Germany, August 29, 2007, [BibTeX, XML].

Keywords: RSerPool, Redundancy, Server Selection, Heterogeneous Pools, Performance Analysis
Abstract: Reliable Server Pooling (RSerPool) is a protocol framework for server redundancy and session failover, currently still under standardization by the IETF RSerPool WG. Server redundancy influences load distribution and load balancing, which both are important for the performance of RSerPool systems. Especially, a good load balancing strategy is crucial if the servers of a pool are heterogeneous. Some research on this subject has already been performed, but a detailed analysis on the question of how to make best use of additional capacity in dynamic pools is still open. Therefore, the aim of this paper is, after an outline of the RSerPool framework, to simulatively examine the performance of RSerPool server selection strategies in scenarios of pools with varying server heterogeneity. In particular, this paper examines and evaluates a simple but very effective new policy, achieving a significant performance improvement in such situations.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/EuroMicro2007.pdf
MD5: b95e9d21968c88bc50bd4d79ea7aac98
Dreibholz, Thomas and Rathgeb, Erwin Paul: ``Towards the Future Internet – A Survey of Challenges and Solutions in Research and Standardization´´ (PDF, 1669 KiB, 🇬🇧), in Proceedings of the 7th Joint EuroFGI and ITG Workshop on Visions of Future Network Generations (EuroView), Würzburg, Bayern/Germany, Poster Presentation, July 23, 2007, [BibTeX, XML].

Keywords: Reliable Server Pooling, SCTP, IPv6, Future Internet
Abstract: The basic intention for the development of the Internet has been the simple and inexpensive interconnection of nodes to provide services like file download or e-mail. However, due to its huge growth and popularity, the classical protocols – which still constitute the basis of today's Internet – have reached their limits of scalability and functionality. Lots of research has been performed in order to overcome these restrictions. On our poster, we would like to give a survey of the challenges on Network, Transport, Session and Application Layer, as well as an outline of solutions which will constitute – from the current perspective in 2007 and with regard to the standardization progress of the IETF – the basis of the Internet in 2022.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/EuroView2007.pdf
MD5: b8be1e85ccd586b858f2b5098a599968
Dreibholz, Thomas: ``Reliable Server Pooling – Evaluation, Optimization and Extension of a Novel IETF Architecture´´ (PDF, 9080 KiB, 🇬🇧), Ph.D. Dissertation, University of Duisburg-Essen, Faculty of Economics, Institute for Computer Science and Business Information Systems, URN urn:nbn:de:hbz:465-20070308-164527-0, March 7, 2007, [BibTeX, XML]. Awarded with the Science Award of the Sparkasse Essen.

Keywords: Reliable Server Pooling (RSerPool), Evaluation, Optimization, Extension
Abstract: The Reliable Server Pooling (RSerPool) architecture currently under standardization by the IETF RSerPool Working Group is an overlay network framework to provide server replication and session failover capabilities to applications using it. These functionalities as such are not new, but their combination into one generic, application-independent framework is. Initial goal of this thesis is to gain insight into the complex RSerPool mechanisms by performing experimental and simulative proof-of-concept tests. The further goals are to systematically validate the RSerPool architecture and its protocols, provide improvements and optimizations where necessary and propose extensions if useful. Based on these evaluations, recommendations to implementers and users of RSerPool should be provided, giving guidelines for the tuning of system parameters and the appropriate configuration of application scenarios. In particular, it is also a goal to transfer insights, optimizations and extensions of the RSerPool protocols from simulation to reality and also to bring the achievements from research into application by supporting and contributing relevant results to the IETF's ongoing RSerPool standardization process. To achieve the described goals, a prototype implementation as well as a simulation model are designed and realized at first. Using a generic application model and appropriate performance metrics, the performance of RSerPool systems in failure-free and server failure scenarios is systematically evaluated in order to identify critical parameter ranges and problematic protocol behaviour. Improvements developed as result of these performance analyses are evaluated and finally contributed into the standardization process of RSerPool.
URL: https://duepublico2.uni-due.de/servlets/MCRFileNodeServlet/duepublico_derivate_00016326/Dre2006_final.pdf
MD5: acdd102ebd0775ca5de523ec5710d800
Dreibholz, Thomas and Rathgeb, Erwin Paul: ``On Improving the Performance of Reliable Server Pooling Systems for Distance-Sensitive Distributed Applications´´ (PDF, 393 KiB, 🇬🇧), in Proceedings of the 15. ITG/GI Fachtagung Kommunikation in Verteilten Systemen (KiVS), Informatik aktuell, pp. 39–50, Springer, DOI 10.1007/978-3-540-69962-0_4, ISBN 978-3-540-69962-0, Bern/Switzerland, February 28, 2007, [BibTeX, XML].

Keywords: Reliable Server Pooling (RSerPool), Server Selection, Load Distribution
Abstract: Reliable Server Pooling (RSerPool) is a protocol framework for server redundancy and session failover, currently under standardization by the IETF RSerPool WG. While the basic ideas of RSerPool are not new, their combination into a single, unified architecture is. Server pooling becomes increasingly important, because there is a growing amount of availability-critical applications. For a service to survive localized disasters, it is useful to place the servers of a pool at different locations. However, the current version of RSerPool does not incorporate the aspect of component distances in its server selection decisions. In our paper, we present an approach to add distance-awareness to the RSerPool architecture, based on features of the SCTP transport protocol. This approach is examined and evaluated by simulations. But to also show its usefulness in real life, we furthermore validate our proposed extension by measurements in a PlanetLab-based Internet scenario.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/KiVS2007.pdf
MD5: 724469ef1a2389ca1d3b3c4e96de5c89

2006

Dreibholz, Thomas: ``RSPLIB – Eine Open Source Implementation von Reliable Server Pooling´´ (PDF, 7868 KiB, 🇩🇪), in Proceedings of the Linuxtage in Essen, Essen, Nordrhein-Westfalen/Germany, September 9, 2006, [BibTeX, XML].

Keywords: Reliable Server Pooling (RSerPool), Hochverfügbarkeit, Redundanz, Überblick, Implementierung, RSPLIB
Abstract: In unserem Vortrag geben wir zunächst eine kurze Einführung zu RSerPool. Dabei wollen wir insbesondere auch die Merkmale verdeutlichen, die RSerPool von existierenden Lösungen – wie Linux Virtual Server (LVS) oder dem kommerziellen Cisco Distributed Director – unterscheiden. Außerdem wollen wir vorstellen, welche speziellen Funktionalitäten RSerPool bietet um den Nutzen eines Serverpools sowohl für dessen Betreiber als auch für den Anwender zu optimieren: die Möglichkeit zur vollautomatischen Konfiguration von Komponenten und die Festlegung pool-spezifischer Serverauswahlregeln. Diese Funktionalitäten werden wir am Beispiel der Anwendung von RSerPool für Real-Time Distributed Computing verdeutlichen. Im zweiten Teil unseres Vortrages werden wir auf unsere Open Source Implementation rsplib eingehen. Neben dem Aufbau der einzelnen Komponenten werden wir insbesondere auch interessante Details der Implementation vorstellen und beschreiben, wie wir auftretende Probleme erfolgreich lösen konnten. Insbesondere wollen wir dabei auch unsere gesammelten Erfahrungen beim Erstellen von auf unterschiedlichen Betriebssystemen und Hardware lauffähiger Software vorstellen. Im Anschluß daran wenden wir uns kurz dem API der rsplib zu und zeigen, wie eigene Programme mit dessen Hilfe hochverfügbar gemacht werden können. Neben neuer, direkt auf RSerPool basierender Software, berücksichtigen wir dabei insbesondere auch die Anpassung bestehender Applikationen und stellen Möglichkeiten zur Migration vor. Zum besseren Verständnis werden sämtliche Beschreibungen von Code-Beispielen begleitet. Zum Abschluß stellen wir noch unsere Beispielanwendung vor, ein System zum verteilten Berechnen von Fraktalgrafiken. Mit diesem System lassen sich die grundlegenden Eigenschaften von RSerPool – welche im ersten Teil des Vortrages vorgestellt wurden – sehr anschaulich demonstrieren: die Verwaltung dynamischer Pools, Lastverteilung und Failover bei PE-Ausfall. Selbstverständlich werden wir unser Beispielsystem beim Vortrag auch praktisch demonstrieren.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/Linuxtage2006.pdf
MD5: c46a9dddc3e7d30f4ab0a8f5372d405b

2005

Dreibholz, Thomas and Rathgeb, Erwin Paul: ``The Performance of Reliable Server Pooling Systems in Different Server Capacity Scenarios´´ (PDF, 679 KiB, 🇬🇧), in Proceedings of the IEEE TENCON, DOI 10.1109/TENCON.2005.300939, ISBN 0-7803-9312-0, Melbourne, Victoria/Australia, November 22, 2005, [BibTeX, XML].

Keywords: Reliable Server Pooling (RSerPool), Server Pooling, Load Distribution, Performance Analysis, Parameter Sensitivity
Abstract: Reliable Server Pooling (RSerPool) is a protocol framework for server pool management and session failover, currently under standardization by the IETF RSerPool WG. While the basic ideas of RSerPool are not new, their combination into one architecture is. Some research into the performance of RSerPool for certain specific applications has been made, but a detailed, application-independent sensitivity analysis of the system parameters is still missing. The goal of this paper is to systematically investigate RSerPool's load distribution behaviour on changes of workload and system parameters, to determine basic guidelines on designing efficient RSerPool systems. In this paper, we focus particularly on scenarios of server pools consisting of servers with unequal capacities.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/Tencon2005.pdf
MD5: ca8319c2b0fa4a6edd7e8bbedd1c4e3e
Dreibholz, Thomas; IJsselmuiden, Avril J. and Adams, John L.: ``An Advanced QoS Protocol for Mass Content´´ (PDF, 113 KiB, 🇬🇧), in Proceedings of the IEEE Conference on Local Computer Networks (LCN) 30th Anniversary, pp. 517–518, DOI 10.1109/LCN.2005.25, ISBN 0-7695-2421-4, Sydney, New South Wales/Australia, November 17, 2005, [BibTeX, XML].

Keywords: Quality of Service (QoS), Signalling Protocols, Telecommunication Congestion Control, Telecommunication Traffic
Abstract: This paper presents a novel network device being located in network edge nodes. It provides a solution for QoS guarantees to certain flows on a congested link by focussing packet discard on selected flows. Unlike IntServ solutions like RSVP, our approach only requires minimal signalling and provides both efficiency and scalability. In this paper, we first describe the ideas of our QoS device and then provide first results from a fast-track simulation model implementing a lightweight version of our approach.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/FlowRouting/Paper/LCN2005-EdgeDevice.pdf
MD5: 081882106105904aa7f496def9022c4e
Dreibholz, Thomas and Rathgeb, Erwin Paul: ``On the Performance of Reliable Server Pooling Systems´´ (PDF, 673 KiB, 🇬🇧), in Proceedings of the IEEE Conference on Local Computer Networks (LCN) 30th Anniversary, pp. 200–208, DOI 10.1109/LCN.2005.98, ISBN 0-7695-2421-4, Sydney, New South Wales/Australia, November 16, 2005, [BibTeX, XML].

Keywords: Reliable Server Pooling (RSerPool), Server Pooling, Load Distribution, Performance Analysis, Parameter Sensitivity
Abstract: Reliable Server Pooling (RSerPool) is a protocol framework for server redundancy and session failover, currently under standardization by the IETF RSerPool WG. While the basic ideas of RSerPool are not new, their combination into one architecture is. Some research into the performance of RSerPool for certain specific applications has been made, but a detailed, application-independent sensitivity analysis of the system parameters is still missing. The goal of this paper, after an application-independent, generic quantification of RSerPool systems and definition of performance metrics for both service provider and user, is to systematically investigate RSerPool's behavior on changes of workload and system parameters to give basic guidelines on designing efficient RSerPool systems.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/LCN2005.pdf
MD5: a3b7091b716b5770343ca3e9bf205597
Silverton, Aron J.; Xie, Qiaobing; Tüxen, Michael and Dreibholz, Thomas: ``Reliable Server Pooling Sockets API Extensions´´ (TXT, 19 KiB, 🇬🇧), Internet Draft draft-ietf-rserpool-api-00, IETF, October 17, 2005, [BibTeX, XML].

Abstract: This document describes a sockets-like API for the Reliable Server Pooling (RSerPool) protocol suite. This API provides applications within an RSerPool enabled system with a reliable communications layer via a highly-available socket interface (rsp_socket).
URL: https://tools.ietf.org/id/draft-ietf-rserpool-api-00.txt
MD5: d9fb76046a89ae415ba233da5a220903
Dreibholz, Thomas and Rathgeb, Erwin Paul: ``RSerPool – Providing Highly Available Services using Unreliable Servers´´ (PDF, 429 KiB, 🇬🇧), in Proceedings of the 31st IEEE EuroMirco Conference on Software Engineering and Advanced Applications, pp. 396–403, DOI 10.1109/EUROMICRO.2005.50, ISBN 0-7695-2431-1, Porto/Portugal, September 2, 2005, [BibTeX, XML].

Keywords: Reliable Server Pooling (RSerPool), Server Pooling, Load Distribution, Performance Analysis
Abstract: The Reliable Server Pooling (RSerPool) protocol suite currently under standardization by the IETF is designed to build systems providing highly available services by mechanisms and protocols for establishing, configuring, accessing and monitoring pools of server resources. Using RSerPool, critical infrastructure services like SS7 telecommunication systems, e-commerce transaction processing or distributed computing can be provided highly available using pools of unreliable servers. In this paper, we first give an overview of the RSerPool framework. In the following, we quantitatively show performance impacts of varying RSerPool parameters to failover handling, server selection efficiency and overhead traffic under server failure conditions.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/EuroMicro2005.pdf
MD5: 79a941c68a985c70e1ff7ea52ab4d344
Dreibholz, Thomas: ``draft-ietf-rserpool-mib-01.txt – Management Information Base Definition for Reliable Server Pooling´´ (PDF, 2249 KiB, 🇬🇧), in Proceedings of the 63rd IETF Meeting, Paris/France, August 1, 2005, [BibTeX, XML].

URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/IETF63.pdf
MD5: d258fb6d483b6d6b69ed97578a489b59
Dreibholz, Thomas: ``Das rsplib–Projekt – Hochverfügbarkeit mit Reliable Server Pooling´´ (PDF, 1154 KiB, 🇩🇪), in Proceedings of the LinuxTag, Karlsruhe, Baden-Württemberg/Germany, June 24, 2005, [BibTeX, XML].

Keywords: Reliable Server Pooling (RSerPool)
Abstract: In unserem Paper geben wir zunächst eine Einführung zu Reliable Server Pooling (RSerPool), danach stellen wir unsere Implementation vor – das rsplib-Projekt. Im Anschluß daran zeigen wir, wie basierend auf unserer Implementation eigene, hochverfügbare Anwendungen mit RSerPool entwickelt werden können – begleitet durch Code-Beispiele. Zum Abschluß stellen wir noch eine unserer Beispielanwendungen vor.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/LinuxTag2005.pdf
MD5: 7e2afb7bb1cc82c458c4ac8217d3f8d0
Dreibholz, Thomas and Rathgeb, Erwin Paul: ``Implementing the Reliable Server Pooling Framework´´ (PDF, 467 KiB, 🇬🇧), in Proceedings of the 8th IEEE International Conference on Telecommunications (ConTEL), vol. 1, pp. 21–28, ISBN 953-184-081-4, Zagreb, Središnja Hrvatska/Croatia, June 15, 2005, [BibTeX, XML].

Keywords: Internet Applications, IPv6 Deployment and Applications, SS7, Server Pools
Abstract: The Reliable Server Pooling (RSerPool) protocol suite currently under standardization by the IETF is designed to build systems providing highly available services by mechanisms and protocols for establishing, configuring, accessing and monitoring pools of server resources. But RSerPool is not only able to manage pools of redundant servers and facilitate service failover between servers: it also includes sophisticated mechanisms for server selections within the pools. These mechanisms make RSerPool useful for the application in load balancing and distributed computing scenarios. As part of our RSerPool research and to verify results of our simulation model in real-life scenarios, we have created a complete implementation prototype of the RSerPool framework. In this paper, we will give a detailed description of the concepts, ideas and realizations of our prototype. Furthermore, we will show performance issues raised by the management of large servers pools, as it is necessary for load balancing or distributed computing scenarios. We will explain the algorithms and data structures we designed to solve these challenges and finally present a rough performance evaluation that verifies our concept.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/Contel2005.pdf
MD5: 31d96cdd656dec8bf3febad099c5cc70
Dreibholz, Thomas; Rathgeb, Erwin Paul and Tüxen, Michael: ``Load Distribution Performance of the Reliable Server Pooling Framework´´ (PDF, 219 KiB, 🇬🇧), in Proceedings of the 4th IEEE International Conference on Networking (ICN), Lecture Notes in Computer Science, vol. 3421, pp. 564–574, Springer, DOI 10.1007/978-3-540-31957-3_65, ISBN 3-540-25338-6, Saint Gilles Les Bains/Reunion Island, April 21, 2005, [BibTeX, XML].

Keywords: RSerPool, Server Pooling, Load Distribution, Performance Analysis
Abstract: The Reliable Server Pooling (RSerPool) protocol suite currently under standardization by the IETF is designed to build systems providing highly available services by providing mechanisms and protocols for establishing, configuring, accessing and monitoring pools of server resources. While availability is one main aspect of RSerPool, load distribution is another. Since most of the time a server pool system runs without component failures, optimal performance is an extremely important issue for the productivity and cost-efficiency of the system. In this paper, we therefore focus especially on the load distribution performance of RSerPool in scenarios without failures, presenting a quantitative performance comparison of the different load distribution strategies (called pool policies) defined in the RSerPool specifications. Based on the results, we propose some new pool policies providing significant performance enhancements compared to those currently defined in the standards documents.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/ICN2005.pdf
MD5: 8b341ae8ee042fbdd1f44392f1672b4e
Dreibholz, Thomas and Rathgeb, Erwin Paul: ``An Application Demonstration of the Reliable Server Pooling Framework´´ (PDF, 330 KiB, 🇬🇧), in Proceedings of the 24th IEEE International Conference on Computer Communications (INFOCOM), Miami, Florida/U.S.A., Demonstration and Poster Presentation, March 16, 2005, [BibTeX, XML].

URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/Infocom2005.pdf
MD5: c9f22eb5c5bb8490a769e5b0d5af6766

2004

Dreibholz, Thomas: ``draft-ietf-rserpool-policies-00.txt – Definition of Member Selection Policies´´ (PDF, 2729 KiB, 🇬🇧), in Proceedings of the 61st IETF Meeting, Washington, DC/U.S.A., November 8, 2004, [BibTeX, XML].

URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/IETF61.pdf
MD5: ef7ef8851a803cd89032050749078808
Dreibholz, Thomas: ``An Overview of the Reliable Server Pooling Architecture´´ (PDF, 66 KiB, 🇬🇧), in Proceedings of the 12th IEEE International Conference on Network Protocols (ICNP), Berlin/Germany, Poster Presentation, October 7, 2004, [BibTeX, XML].

Keywords: Reliable Server Pooling (RSerPool), Overview, Implementation, RSPLIB
Abstract: The convergence of classical PSTN and IP networks requires the transport of SS7 signalling over IP. Since SS7 has very strict availability requirements to the signalling components, redundancy is mandatory. The goal of the IETF RSerPool working group is to define a lightweight, flexible and realtime redundancy concept to fulfil the availability requirements of SS7: Reliable Server Pooling (RSerPool). RSerPool is currently under standardization, its functionality and improvement are subject of our research. Our poster presents our RSerPool proof-of-concept implementation and a research oriented, discrete event based simulation model. We provide some simulation results showing problems of the server selection procedures defined in the standards and how we solved them. These improvements are now going into standardization by the IETF. Furthermore, we present some of our important results on efficient algorithms and data structures for pool management. The poster concludes with an outlook on our currently progressing examinations of service reliablity in failure scenarios.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/ICNP2004.pdf
MD5: fa721e916781e49ca93719c3c7314dfe
Dreibholz, Thomas: ``Member Selection Policies for the Reliable Server Pooling Protocol Suite´´ (PDF, 3299 KiB, 🇬🇧), in Proceedings of the 60th IETF Meeting, San Diego, California/U.S.A., August 5, 2004, [BibTeX, XML].

URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/IETF60.pdf
MD5: df00a537e3bf39fca4e5e7ba2ba2e0b4
Dreibholz, Thomas; IJsselmuiden, Avril J. and Adams, John L.: ``Simulation of an Advanced QoS Protocol for Mass Content´´ (PDF, 248 KiB, 🇬🇧), in Proceedings of the 2nd International Conference on Performance Modelling and Evaluation of Heterogeneous Networks (HET-NETs), Ikley, West Yorkshire/United Kingdom, July 26, 2004, [BibTeX, XML].

Keywords: Quality of Service (QoS), Signalling Protocols, Telecommunication Congestion Control, Telecommunication Traffic
Abstract: This paper describes a new network device to be located in network edge nodes. The device can deal with congestion conditions that may arise when, for example, a home or SME customer requests too many simultaneous flows to be forwarded down a DSL link or other access technology. It provides a solution to guaranteeing certain flows that are forwarded along one or more congested links, by making others (typically the latest flow, or another flow selected because of policy reasons), the subject of focused packet discards. The functionality of the device is described, and results from a fast-track simulation model implementing a lightweight version of the device, developed in LISP, are presented here.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/FlowRouting/Paper/HET-NET2004-Paper.pdf
MD5: 1e3573935ab2e0b86e9d3288dbc7109d
Dreibholz, Thomas: ``Policy Management in the Reliable Server Pooling Architecture´´ (PDF, 4930 KiB, 🇬🇧), in Proceedings of the Multi-Service Networks Conference (MSN, Coseners), Abingdon, Oxfordshire/United Kingdom, July 8, 2004, [BibTeX, XML].

URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/MSN2004-Final-with-Examples.pdf
MD5: 0bfcc62620e0a0abd20ad6d18e2c4ce1

2003

Dreibholz, Thomas; Jungmaier, Andreas and Tüxen, Michael: ``A New Scheme for IP-based Internet Mobility´´ (PDF, 210 KiB, 🇬🇧), in Proceedings of the 28th IEEE Local Computer Networks Conference (LCN), pp. 99–108, DOI 10.1109/LCN.2003.1243117, ISBN 0-7695-2037-5, Königswinter, Nordrhein-Westfalen/Germany, October 22, 2003, [BibTeX, XML].

Keywords: Internet, Cellular Radio, Transport Protocols, Stream Control Transmission Protocol (SCTP), Reliable Server Pooling (RSerPool)
Abstract: In this contribution we present a new type of mobility management for IP-based networks that, contrary to conventional approaches, does not focus on the network layer, but on the transport and session layers. At the heart of this new mobility concept is the reliable transport protocol SCTP, with an enhancement for dynamic address reconfiguration. This is described in this paper. A session layer based on the reliable server pooling (RSerPool) protocol suite provides for sessionmonitoring and control. The suggested solution is transparent for applications,requires no changes in the network infrastructure, and is evaluated with a real-world implementation. Finally, we present first results from the application of this mobility concept to different mobility scenarios. These were obtained from working SCTP and RSerPool implementations that have been developed within our group.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/LCN2003.pdf
MD5: 7b3fdad55551f9a7c57d8f92340ab14a
Dreibholz, Thomas; Smith, Avril J. and Adams, John L.: ``Realizing a Scalable Edge Device to Meet QoS Requirements for Real-Time Content Delivered to IP Broadband Customers´´ (PDF, 112 KiB, 🇬🇧), in Proceedings of the 10th IEEE International Conference on Telecommunications (ICT), vol. 2, pp. 1133–1139, DOI 10.1109/ICTEL.2003.1191595, ISBN 0-7803-7661-7, Papeete/French Polynesia, February 26, 2003, [BibTeX, XML].

Keywords: Quality of Service (QoS), Bandwidth Guarantee, Admission Control, Congestion Control, Intelligent Packet Dropping, Edge Node, Security, Implementation Considerations
Abstract: With DSL technology becoming widespread, more and more customers have access to high-speed Internet backbones. Such links not only speed up classical best effort applications but also make new applications like video and audio on demand possible. Unlike best effort applications, these new applications have more requirements for network quality of service, especially an assured bandwidth. Under the assumption that the link to the customer is the main bottleneck, this paper presents a new simple, scalable edge node approach that has been developed in a cooperation between the University of Essen and British Telecom (BT). It provides a solution to guaranteeing certain flows, while making others the subject of focused packet discards. While the performance aspect of this new device is currently under research, this paper lays its focus on implementability and especially provides a security concept.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/FlowRouting/Paper/EdgeDevice-Paper.pdf
MD5: 7c37d41dd417062ba4fd17063d846939
Dreibholz, Thomas and Tüxen, Michael: ``High Availability using Reliable Server Pooling´´ (PDF, 79 KiB, 🇬🇧), in Proceedings of the Linux Conference Australia (LCA), Perth, Western Australia/Australia, January 24, 2003, [BibTeX, XML].

Keywords: Reliable Server Pooling (RSerPool), Server Pooling, RSPLIB
Abstract: Providing fault tolerancy is crucial for a growing number of IP-based applications. There exist a lot of proprietary solutions for this problem, but free alternatives are rare. Currently, the IETF RSerPool working group is standardizing a protocol suite for Reliable Server Pooling, which copes with the challenge of providing high availability by using redundant servers. Servers for the same service are grouped into a server pool. A server in a pool is called pool element (PE), a user of a pool is called pool user (PU). When a PE fails, its PUs simply select another one from the pool and initiates an application-specific failover procedure. This fail-over is supported by the RSerPool protocol suite. Each PE registers at a name server and is then continously supervised by that specific name server. All name servers of an operational scope provide a redundant system for name resolution from pool handles to transport addresses of pool elements to pool users. RSerPool uses SCTP to provide network fault tolerance and address scoping functionality. The RSPLIB is a prototype implementation of the RSerPool protocol suite, developed under the GNU Public License in cooperation between Siemens and the Computer Networking Technology Group of the University of Essen. It currently runs under Linux, FreeBSD and Darwin. Our paper covers aspects of designing and implementing highly available applications using RSerPool with our RSPLIB implementation. First, we will give an introduction to the RSerPool protocol suite and an overview of the RSPLIB components. Then, we describe the RSPLIB API, especially focussing on the implementation of pool element and pool user programs to provide high reliability. Furthermore, we show our current implementation status and future plans. This will be followed by a short look on the problems that can arise when the RSerPool architecture is used. Finally, we give an example how RSerPool can be used to realize highly available services. And last but not least, we show how distributed computing architectures can make use of the RSerPool architecture.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/RSerPool-Paper.pdf
MD5: eac12b5e0912b99b881727f2fc096970

2002

Dreibholz, Thomas: ``An Efficient Approach for State Sharing in Server Pools´´ (PDF, 111 KiB, 🇬🇧), in Proceedings of the 27th IEEE Local Computer Networks Conference (LCN), pp. 348–349, DOI 10.1109/LCN.2002.1181806, ISBN 0-7695-1591-6, Tampa, Florida/U.S.A., November 8, 2002, [BibTeX, XML].

Keywords: Reliable Server Pooling (RSerPool), Server Pooling, State Sharing, Client-Based State Sharing, State Cookies
Abstract: Many Internet services require high availability. Server pooling provides a high availability solution using redundant servers. If one server fails, the service is continued by another one. A challenge for server pooling is efficient state sharing: The new server requires the old one's state to continue service. This paper proposes a simple, efficient and scalable solution, usable for a large subset of applications.
URL: https://www.wiwi.uni-due.de/fileadmin/fileupload/I-TDR/ReliableServer/Publications/StateSharing-Paper-ShortVersion.pdf
MD5: f1f40c62426deb84eb7dbe5a0d1d75c9

2001

Dreibholz, Thomas: ``Management of Layered Variable Bitrate Multimedia Streams over DiffServ with Apriori Knowledge´´ (PDF, 60591 KiB, 🇬🇧), Masters Thesis, University of Bonn, Institute for Computer Science, URN urn:nbn:de:hbz:464-20120416-095753-8, February 20, 2001, [BibTeX, XML].

Keywords: Multimedia, Quality of Service, Layered Transmission, DiffServ, A Priori Knowledge
Abstract: The Internet is developing with a very high speed. Just a few years ago, its main applications were file transfer and e-mail access, all based on the best effort TCP/IP service over quite slow links. With the quickly growing deployment of high-speed Internet accesses, there is a growing demand for also using the Internet in application scenarios like real-time multimedia streaming, particularly for audio and video on demand services. However, such multimedia applications do not only require sufficient bandwidth. They have stricter quality of service demands, like e.g. an upper bound on the transfer delay to ensure interactivity for their users. In the context of this thesis, a system for the cost-efficient transfer of variable bitrate multimedia streams over Differentiated Services (DiffServ) is presented and evaluated. This system supports layered transmission, i.e. streams may be partitioned into sub-streams denoted as layers (e.g. a video layer and an audio layer). Distinct layers may have different priorities as well as quality of service requirements and may therefore use different DiffServ classes for data transmission. Also, the streams may be scalable, i.e. the quality of the transferred media may be decreased in order to reduce the bandwidth requirements when bandwidth becomes scarce. Particularly, the system makes use of the fact that media files in e.g. a video on demand library can be analyzed a priorily. The information that is computed during the offline analysis is used to realize a dynamic and cost-efficient transport of layer data over different DiffServ classes. Furthermore, the system applies an adaptive buffering to smooth the flows – in order to save bandwidth – while also taking care of the delay constraints.
URL: https://duepublico.uni-duisburg-essen.de/servlets/DerivateServlet/Derivate-29936/Dre2001.pdf
MD5: 479cc723184d88dbce6864ab93f9b6c0

2000

Dreibholz, Thomas; Selzer, Jan and Vey, Simon: ``Echtzeit-Audioübertragung mit QoS-Management in einem DiffServ-Szenario´´ (PDF, 4322 KiB, 🇩🇪), Projektseminararbeit, Universität Bonn, Institut für Informatik, August 14, 2000, [BibTeX, XML].

Keywords: Quality of Service (QoS), Real-Time, Audio, DiffServ, RTP Audio
URL: https://www.nntb.no/~dreibh/rn/DSV00.pdf
MD5: 9aed1f5be5c1badcd41efe3e414614c0

Simula Research Laboratory Center for Resilient Networks and Applications Homepage of Thomas Dreibholz