MULTI-LEVEL STEGANOGRAPHY OVER THE TCP/IP

Abstract

To perform hidden communication through the network, network protocols and/or relationships between them have been utilized as a carrier to transmit secret data. For each network steganography method there is always a trade-off necessary between maximizing steganographic bandwidth (how much data we are able to send using this particular method) and still remaining undetected. In this work a new steganographic method is developed that aims to achieve undetectability and relatively increase steganographic bandwidth. This method depends completely on concept called Multi Level steganography (MLS). In MLS, at least two steganographic methods are utilized simultaneously in such a way that one method’s (the upper-level) network traffic serves as a carrier for the second method (the lower-level). Experimental results were obtained demonstrating that the average transmission time of network decreased by 14.8% due to using of MLS, and the time required to transfer steganogram file of size equal to 50 bytes through the system is 166.43 seconds, about (2 minutes and 46 seconds).