vkg AT {acm.org,bell-labs.com,alcatel-lucent.com}

I am a Distinguished Member of Technical Staff in the Computer Systems and Security Research group in the Enabling Computing Technologies Domain at Bell Labs, Alcatel-Lucent.

Since 1998, I have been working on multimedia signaling protocols, especially Session Initiation Protocol (SIP). In recent years, I have started to work on systems-related security areas for SIP in particular and Voice-over-IP (VoIP) in general. More recently, I have also been studying peer-to-peer (p2p) networks and distributed hash tables, especially in the context of supporting VoIP as an application.

I am a TPC co-chair of the IEEE Internet Multimedia Systems and Applications Conference (IMSAA) conference that will be held in Bangalore, India in December 2009. In addition, I am the TPC co-chair of the 2010 IPTComm conference that will be held in early August 2010 at the Leibniz Supercomputing Center in Munich, Germany.

I am fairly active in the Internet Engineering Task Force (or IETF), especially in the SIP-related working groups. I also co-chair the Application Layer Traffic Optimization (or ALTO) working group where we are designing a protocol that will provide p2p applications with information to perform better-than-random initial peer selection. We hold regular working group meetings during the IETF conferences. The audio discussion, slides and minutes from these meetings are archived here.

The ALTO working group attracted fair amount of press when it was in the process of being formed. When we met as a BoF session in the Dublin IETF (Aug, 2008), Heise Online printed this. Their coverage of our Minneapolis meeting resulted in this. Things have quieted down more recently as the novelty of the working group has worn off.