An analysis of IP Multimedia Subsystems (IMS)

This paper analyzes the complexity of IP multimedia subsystems (IMS) proposed by 3GPP/3GPP2. Using two different mobility models, the paper provides a methodology to determine the number of accesses to the IMS servers. The analysis considers mobility of users across registration areas, which generates IMS registration requests as well as signaling to IMS servers due to service requests initiated by users. This analysis is intended to guide network architects and designers in sizing IMS deployments and to help them improve the utilization of IMS systems.