The IP multimedia domain in wireless networks: concepts, architecture, protocols and applications

The IP multimedia subsystem (IMS) is defined by the 3/sup rd/Generation Partnership Project (3GPP) as a new core network domain. IMS provides a service control platform that allows creation of new multimedia and multisession applications utilizing wireless and wireline transport capabilities. In this paper we cover the concepts and standards defining IMS and review the network architecture from a mobile perspective. We see how IMS interacts with the packet switched domain (e.g. wireless LAN, GPRS, and UMTS networks), the circuit switched domain (e.g. GSM networks), the Internet, and application services. We examine the key IMS capabilities and show how they can be combined to create new mobile IP services. Finally, we present the software architecture that allows development of unique applications (with multimedia/multisession functionality, single/multiuser, service to user), enabled by IMS.