Mitigation of Flooding Based Denial of Service Attack against Session Initiation Protocol Based VoIP System

The Session Initiation Protocol (SIP) is the most popular signaling protocol used in Voice over Internet Protocol (VoIP). The flooding based DoS attack can be performed by sending only hundreds of SIP messages per second to a SIP server. In this paper, we have proposed a new mitigation scheme for SIP based VoIP system which can protect it from flooding based DoS attack. This scheme is based on the INVITE and BYE messages of the SIP protocol. A prototype system for the flooding based DoS attack on SIP server and a mitigation mechanism has been designed and implemented. The performance of the proposed system has been evaluated and found to be better than other existing mechanisms.