YouSkyde: Information Hiding for Skype Video Traffic
  In this paper a new information hiding method for Skype videoconference calls - YouSkyde - is introduced. A Skype traffic analysis revealed that introducing intentional losses into the Skype video traffic stream to provide the means for clandestine communication is the most favourable solution. A YouSkyde proof-of-concept implementation was carried out and its experimental evaluation is presented. The results obtained prove that the proposed method is feasible and offer a steganographic bandwidth as high as 0.93 kbps, while introducing negligible distortions into transmission quality and providing high undetectability. 
Wojciech Mazurczyk, Maciej Karas, Krzysztof Szczypiorski, Artur   Janicki
cs.CR cs.MM