Summary

In general, IP multimedia subsystem (IMS) implementation is based on a set of standards developed by different standards development organizations (SDOs). In this regard, there is an intention to develop a Recommendation which lists the references to specifications defining requirements for IMS to be used for the non‑roaming architecture for 3GPP access as a basis for the communication between IMS and next generation networks (NGNs), in order to support end-to-end service interoperability.