Architecture of IP Multimedia Subsystem

IP multimedia subsystem (IMS) is standardized network architecture for telecom operators that want to provide mobile and fixed multimedia services. IMS-enabled networks provide access to these services from both IP networks and circuit-switched PSTN/PLMNs. This paper describes the IMS architecture and explains its benefits. It concentrates on the main IMS system components and briefly summarizes their key system functions. However, the IMS is a rapidly evolving standard and modifications to the IMS architecture are envisaged. This paper provides a base for future research and work in this domain