Research On Sip Security Authentication Mechanism Based On IMS

SIP is a signaling control protocol of the application layer proposed by the Internet Engineering Task Force (IETF), used to control the signaling in IP network. More and more telecommunications service providers begin to use SIP protocol as its flexibility and scalability. However, SIP protocol lack of effective security authentication mechanism, so it is necessary to carry out more in-depth study of its security mechanisms.This paper analyzes five security threats suffered by SIP, including registration hijacking attack, server impersonating attack, message tampering attack, session tearing down attack and denial of service attack, and then describes the existing SIP security mechanism, and analyzes principle and security flaws of HTTP digest authentication.On this basis, this paper makes use of one-time password authentication and digital signature technology to improve HTTP digest authentication. At last, this paper analyzes the improved security authentication program in terms of security and efficiency, and then tests this improved security mechanism. The result shows that the security mechanism can prevent SIP attack effectively.