Having stable and uninterrupted Internet connectivity is becoming increasingly important, particularly with regard to applications like cloud computing, service as a platform and many others. Connectivity problems could e.g. be caused by a hardware failure or a natural disaster. In order to improve the robustness of Internet connectivity, it is obvious to connect endpoints to multiple Internet service providers (ISP) simultaneously. This property is denoted as multi-homing. For example, Transport Layer protocols like the Stream Control Transmission Protocol (SCTP, RFC 4960) or Session Layer frameworks like Reliable Server Pooling (RSerPool, RFC 5351) make use of multi-homing to support availability-critical applications.
However, while in theory a failure of one ISP should be independent of other ISPs, it is not really known what happens in practise in today’s commercial networks. It is evident that there are hidden dependencies among ISPs. Also, what about connectivity problems due to intentional malicious behaviour, i.e. targeted attacks on such systems? How can multi-path transport – e.g. with Multi-Path TCP (MPTCP) or Concurrent Multipath Transfer for SCTP (CMT-SCTP) – efficiently and fairly make use of multi-homing? Research in realistic Internet setups is clearly necessary, in order to answer these open questions. For that purpose, the NorNet project is building up a multi-homed testbed distributed all over the country of Norway. This programmable testbed is to be used for measurements and experimental networking research. It is built and operated by the Simula Research Laboratory and financed by Forskningsrådet (the Research Council of Norway) through their INFRASTRUKTUR program (project number 208798/F50).
NorNet has two main components: NorNet Core and NorNet Edge. NorNet Core consists of more than tvelve programmable sites, each multi-homed to several network providers. NorNet Edge consists of several hundreds of smaller nodes that are connected to all mobile broadband providers in Norway. Together, these two components offer a unique platform for experimental networking research. NorNet is made available to the Norwegian and international networking research community.