Seamless multimedia service continuity with 3GPP IMS approach

With the rapid development of mobile communication and packet-switched technologies, it is inevitable to discover the suitable solutions to integrate these networks and to provide users the consistency and continuity of services through diverse access networks. In this paper, we analyse the fundamental criteria for the suitable solutions based on 3GPP TR22.937 and WiMAX Forum requirements; the requirements are subcategorized into five criteria, which are common billing and customer care, common access control, policy and charging, service session continuity, seamless service access and unified user identity. Through these requirement criteria, several mobility support techniques are compared and evaluated. This paper further examines IP Multimedia Subsystem (IMS) approaches defined in 3GPP standards for supporting seamless service continuity from the aspects of these criteria. Consequently, the challenges and drawbacks of IMS from the aspects of architecture, protocol signalling and interoperability are later overviewed in this paper.