Cross-Layer Mobility Management based on Mobile IP and SIP in IMS

IP multimedia subsystem ( IMS ) is a new network architecture for providing multimedia service in the next generation wireless networks, 3GPP has chosen session initiated protocol ( SIP ) to be the signaling protocol in IMS. At present, IMS can only support nomadic mobility but not seamless mobility. So a new solution is required to support seamless mobility in IMS. In this paper, we proposed a new cross-layer mobility management solution based on the integration of Mobile IP and SIP. In our proposed solution, we introduce a cross-layer module between home agent and S-CSCF, which can realize information exchange between network layer and application layer. Through the cross-layer module, the binding update message received by home agent can be translated and forwarded to S-CSCF to trigger the registration procedure in IMS. So the signaling between mobile node and home network can be reduced dramatically. Finally, we analyzed our proposed three mobility management solutions theoretically and made simulations based on our analysis. The simulation results demonstrated that the cross-layer mobility management solution brings smaller handoff delay and lower signaling overhead to the network than the other two solutions. So we can conclude that cross-layer mobility management solution can provide better mobility management for real-time service in IMS and achieve good scalability.