Date Added: Jan 2013
Peer-to-peer VoIP calls are popular due to their low cost and convenience. When these calls are encrypted and anonymized the network becomes a secured one. Tracing of the anonymous VoIP call users are important and the traced information about them should be sent to the server to know how long the users are in communication. The key challenge in tracking encrypted VoIP calls across anonymous communication system is to identify the correlation between the VoIP flows of the caller and the callee. Since all the traffic of the peer-to-peer VoIP calls are encrypted, the best way to track anonymous VoIP calls across the internet is using the Active timing based correlation. It is done by embedding a unique watermark into the inter-packet timing domain.