Realization and Defense of Redirection Attack on SIP

Session Initiation Protocol(SIP)is the most popular protocol for mult-media session control,it is an application-layer control protocol,used for establishing,modify,and terminate multimedia sessions(conferences)such as Internet tele-phony calls.SIP is a text-based protocol,and quite vulnerable to simulating and tampering by attacker.This paper discusses the realization of a new attack,redirection attack.Finally it proposes the security mechanism for protecting SIP from this attack.