Security mechanisms for SIP-based multimedia communication infrastructure

We have proposed a generic SIP-based application topology model called secure multimedia communication infrastructure (SMCI) and constructed a real multimedia communication application based on it. We now emphasize the security issues in the SMCI and give the entire secure framework in detail. We also analyze the processing load of our security mechanism in order to explain the practicability of our secure framework. Hop by hop and end to end security are introduced to defend the attacks of registration hijacking, impersonating a server, tampering with message bodies, tearing down sessions, denial of service and amplification. We also considered the privacy problem that will be the most important consideration in the future. Finally, a security analysis is presented to demonstrate that the proposed security mechanisms are robust and efficient to secure the SMCI.