Based On The Research And Realization Of The Covert Communication System For Multimedia Data Network Communication

With the rapid development of electronic information and the network applications, the information security in Internet has become increasingly prominent. The covert communication technology based on network multimedia transmission is arising technique that combining of network-based multimedia transmission technology and information hiding theory. It holds the great signification to secure the safe transmission of the confidential information, therefore, received more and more attention of the academics and research institutions. At the same time, with the deepening and development of network in e-commerce, political and military aspects, the covert communication technology based on network multimedia transmission, which is the developing direction of the information hiding technique, has become an important insurance on confidential information transportation. The main assignment of the thesis including:(1). Study the specific works of the VoIP in the network, and establish the voice communication platform based on H.323 signaling protocol.(2). Present a kind of information hiding system based on VoIP platform and embed the confidential information into the audio data with the improved LSB algorithm, in order to achieve the secure transmission of confidential information.(3). On this basis, all parts'performance of this system are verified, including the time delay and impact of the original audio quality caused by embedding process. Meanwhile, a kind of re-transmission mechanism is presented to protect the integrity of the confidential information which is threatened by packet-loss in network.Proved by these experiments, the information hiding system based on VoIP platform proposed in this paper is safe, real-time and covert. Through this analysis of the system, it is proved that this scheme of covert communication is simple, safe and, more importantly, effective. Therefore, this topic has important meaning, theoretically and practically, to the field of information security in networks, furthermore, has certain practical prospects.