Performance Modelling and Evaluation of Handover Mechanism in IP Multimedia Subsystems

IP multimedia subsystems (IMS) is using session initiation protocol (SIP) as signalling protocol. SIP is becoming computing intensive and hence the ability of entry and exit proxies to process SIP messages has great impact on the overall performance of the IMS core network. This paper shows that the flow of SIP messages during handover process in the IMS core network complies with the well known central server model. The later is validated via discrete event simulation results. The performance prediction study reveals that S-CSCF is the bottleneck device of the IMS core network processing a large number of SIP messages.