Voice-over-IP (VoIP) communication based on the Session Initiation Protocol (SIP) has evolved as de-facto standard for voice communication. However, the popularity and low cost of SIP system deployments in the Internet make it an interesting attack target. The VoIP misuse detection project of the University of Duisburg-Essen applies NorNet Core systems to analyse such attacks in the real Internet. To understand attack patterns and getting information on security weaknesses is important in order to take appropriate countermeasures against such attacks. NorNet therefore helps to make VoIP application in the Internet more secure!
See http://www.tdr.wiwi.uni-due.de/en/projects/research-projects/voip-security/ for further details!