关键词: SIP, SDP, HTTP摘要, 质询, 应答

Abstract: The construction of safe city, it is the key ofsecurity authentication forclien in video monitoring system. In order to make up for the lack of security of SIP, an authentication scheme has been designed based on HTTP digest. Firstly, the principle of SIP and HTTP protocol is analyzed, and it designs the whole structure of video monitoring system, and defines the function of each main component. Then, it designs the scheme of login-Ncancellation and achieving the property list of equipment. Finally, it designs the implementation scheme which include scertification process, chcallenge message header of AG, response message header of MC and parameter of Response. The design idea, in the paper, has a certain reference significance for improving the security of SIP protocol.

Key words: session initiation protocol, session description protocol, HTTP digest, chanllenge, response