A New Hybrid Method for VoIP Stream Steganography

In this article, a new stream steganography method for real time digital data network environment with the focus on VoIP is presented. This method consists of a combination of Least Significant Bits (LSB) algorithm and an algorithm called LACK, which is based on the delayed packets in VoIP streams, and forms a new algorithm called LASB (LACK-LSB combination). The combination allows both the reduction of detection probability of stegano data and the use of LSB high capacity as well as being more robust because of diversifying the source of data embedding. That is, by combing these two methods the probability of detection existing steganography data is reduced extensively. Moreover, in the case of detecting stegano data, the potential eavesdropper is not able to easily reconstruct it. To show the performance, both LACK and LSB algorithms are implemented and are compared with the new LASB algorithm in the VoIP environment in terms of capacity, eavesdropping and robustness under several attacks. The experimental results show that LASB is superior to both LACK and LSB in many aspects.