Towards Adaptive Covert Communication System

Abstract

Covert channels are secret communication paths, which existance is not expected in the original system design. Covert channels can be used as legimate tools of censorship resistance, anonimity and privacy preservation to address issues with "national" firewalls, citizen profiling and other "unethical" uses of information technology. Current steganographic methods that implement covert channels within network traffic, are highly dependent on particular media data or network protocol to hide data. In this paper we investigate the methods and an algorithm for implementing adaptive covert communication system that works on real-world Internet, capable of using multiple application-level protocols as its communication media and can be implemented as network application, therefore requires no system modifications of communicating nodes. The key difference from previous solutions is the use of adaptive redundant mechanism, which allows real-time underlying protocol switching and adaptation to the dynamic network configuration changes.