New Steganography method TranSteg hides Data in VoIP(IP Telephony)
Researchers from Warsaw University of Technology, Institute of Telecommunications find a new Steganography method that helps to hide the Data in VoIP(IP Telephony). The method is named as "TranSteg((Transcoding Steganography)".
Voice over IP (VoIP), or IP telephony, is one of the services of the IP world that is changing the entire telecommunication’s landscape. It is a real-time service, which enables users to make phone calls through data networks that use an IP protocol.Steganography encompasses various information hiding techniques, whose aim is to embed a secret message(steganogram) into a carrier (image,audio,video). Steganographic methods are aimed at hiding of the very existence of the communication, therefore any third-party observers should remain unaware of the presence of the steganographic exchange.
In TranSteg it is the overt data that is compressed to make space for the steganogram. The main innovation of TranSteg is to, for a chosen voice stream, find a codec that will result in a similar voice quality but smaller voice payload size than the originally selected. Then, the voice stream is transcoded. At this step the original voice payload size is intentionally unaltered and the change of the codec is not indicated. Instead, after placing the transcoded voice payload, the remaining free space is filled with hidden data. TranSteg proof of concept implementation was designed and developed.
TranSteg detection is difficult to perform when performing inspection in a single network localisation.