Design And Implementation Of Secure Multimedia Communication Protocol

Nowadays people pay more and more attention to the secure transmission of Internet multimedia information. While higher data confidentiality is proposed under circumstances of higher sensitivity cases like private data, business data or political and military data. Multimedia streaming transmission technology standards includes ISMA pattern based on internet, MPEG-2 TS based on radio and TV net. SRTP and MIKEY protocol are secure mechanism for ISMA pattern. Research on the secure transmission technology of MPEG-2 TS is seldom although it is the primary encapsulating standard in the field of multimedia. There is no secure protocol or key management protocol to support the secure transmission of MPEG-2 TS. In consideration of real time performance, the transmission of multimedia is mostly based on UDP which is unreliable connection, so it is necessary to provide an effective key synchronization scheme for the reasons of packets losing and out-of-order when cipher data is transmitted.MIKEY takes advantage of less negotiating information, short delay, less calculating amount, so it is suitable for transmission of multimedia. But MIKEY is a key management protocol design for SRTP, it can not be applied for MPEG-2 TS directly. In this thesis, we designed a secure transmission protocol based on MPEG-2,the related research findings are listed as follows.(1) On the basis of MIKEY, we designed an authenticated key establishment process. We replaced timestamp with challenge/response, mapped MPEG-2 TS parameters to right places. We illustrated the modification based on MIKEY.(2) We proposed two key synchronization schemes respectively based on the privilege of modifying packets to ensure that the server can decrypt cipher stream correctly.(3) The security analysis of protocol shows that it can resist replay attacks, man-in-the-middle attacks and denial-of-service attacks.(4) We proposed an expansion schemes which can be applied when the computing power of client is weak, we also give a comparion of calculated amount and security.(5) We implemented the protocol and also described the implementation of RSA-1.5 and modules. We tested the delay of protocol and key synchronization scheme, analyzed the performance according to the test results.Finally, some open issues in the field of secure multimedia communication and the future work are presented.