SkyDe: a Skype-based Steganographic Method


  • Wojciech Mazurczyk Warsaw University of Technology
  • Maciej KaraÅ› Warsaw University of Technology
  • Krzysztof Szczypiorski Warsaw University of Technology


Information hiding, network steganography, Skype


This paper introduces SkyDe (Skype Hide), a new steganographic method that utilizes Skype encrypted packets with silence to provide the means for clandestine
communication. It is possible to reuse packets that do not carry voice signals for steganographic purposes because Skype does not use any silence suppression mechanism.
The method’s proof-of-concept implementation and first experimental results are presented. They prove that the method is feasible and offers steganographic bandwidth as high as 2.8 kbps.


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