Detection the covert channels based on MSN VoIP
Wang Jun · Journal of Tsinghua University(Science and Technology) · 2009
Covert communications are widely used in network communications and media streams,so detection of the information hidden in these data streams is a key issue in information security.Since microsoft service network(MSN) Messenger is one of the most widely used Internet communication protocols currently,this paper presents method to analyze the features of MSN VoIP(voice over IP) packets to identify convert information.A sliding window method is used to sample the VoIP stream to detect covert communications using steganography on the PCM(pulse code modulation) speech code using the LSB(least significant bit) algorithm.These methods effectively provide real-time online detection of covert communications.Tests demonstrate that these methods achieve better performance,with a high identification ratio for MSN VoIP streams and a high correctness ratio in covert communication detection.Hence,these methods can provide practical steganalyses.