[VOIPSEC] Real-time Steganography with RTP

[Dan Wing]

http://www.uninformed.org/?v=8&a=3&t=txt

Real-time Steganography with RTP
September, 2007
I)ruid, C²ISSP
druid at caughq.org
http://druid.caughq.org


Abstract: Real-time Transfer Protocol (RTP) is used by nearly all
Voice-over-IP systems to provide the audio channel for calls.  As
such, it provides ample opportunity for the creation of a covert
communication channel due to its very nature.  While use of
steganographic techniques with various audio cover-medium has been
extensively researched, most applications of such have been limited to
audio cover-medium of a static nature such as WAV or MP3 file audio
data.  This paper details a common technique for the use of
steganography with audio data cover-medium, outlines the problem
issues that arise when attempting to use such techniques to establish
a full-duplex communications channel within audio data transmitted via
an unreliable streaming protocol, and documents solutions to these
problems.  An implementation of the ideas discussed entitled SteganRTP
is included in the reference materials.