Terminating session handling
3GPP has specified how to combine CS call and IMS Sessions but has not yet addressed the interworking between e.g. a pure IMS voice/video session and a combination of a CS call and an IMS session.
The present document studies how to handle terminating real-time sessions and calls taking into account different domains (CS, IMS) and different UE capabilities (CSI, IMS VoIP, etc.).