Queuing strategies for self overload control in SIP servers

The Session Initiation Protocol is an IP based application level signaling protocol. SIP is used for locating end users, establishing, modifying and closing multimedia sessions between end users. SIP uses various overload control techniques out of which self overload control using different queuing strategies is one. This paper identifies the problem arising due to retransmission of SIP requests in priority queuing model and introduces a smart priority queuing model to reduce the retransmissions by giving high priority to retransmitted requests and avoids transmitting unnecessary retransmissions downstream of SIP network.