Hidden Information Based On Real-time Voice Communication Technology Research

With the development of the internet technology, the question of information security becomes the focus gradually. Information hiding is an important branch of the information security subject, it can securely transmit information by hiding the secret information into the public carriers.At the same time, the instant messaging technology is also developing rapidly. Instant messaging software, such as QQ,MSN,Gtalk and so on, become a necessity in people'life. Prior to this, the real-time voice communication has many features that it has a large amount of data and is used widely. So, real-time voice data becomes an ideal vehicle for information hiding.This paper has analyzed the voice protocol of Gtalk provided by Google with the real-time voice as information hiding carrier. And study detailed the information hiding technology based on instant messaging from two aspects that voice data and voice protocol. In the aspect of voice protocol, the paper proposes a new method of hiding information based on RTP time stamp for the real-time transmission protocol, and elaborates specific design idea and process and analyzes specifically hiding properties. In order to ensure the reliability of hidden information transmission, a synchronization mechanism is proposed for time stamp hidden program. In the aspect of voice data, according to encoding features, the paper proposes an adaptive method of hiding information based on code section for G.711 encoding, and elaborates specific design idea and process,and also analyzes specifically hiding properties. On the basis of ensuring the reliability of information transmission, the paper proposes a synchronization mechanism and shows the method of identifying RTP voice stream. In the last, the paper verifies the feasibility of the two hiding information methods with Gtalk voice stream as hiding carriers.