K.2 Overall architecture

23.2283GPPIP Multimedia Subsystem (IMS)Release 18Stage 2TS

Figure K.1 illustrates an high-level architecture diagram showing the Inter-IMS Network to Network Interface (II-NNI) between two IM CN subsystem networks.

Figure K.1: Inter-IMS Network to Network Interface between two IM CN subsystem networks

The protocols over the two reference points Ici and Izi make up the Inter-IMS Network to Network Interface.

The Ici reference point allows IBCFs to communicate with each other in order to provide the communication and forwarding of SIP signalling messaging between IM CN subsystem networks. The Izi reference point allows TrGWs to forward media streams between IM CN subsystem networks.

NOTE: Whenever the Inter-IMS Network to Network Interface is used to interconnect two IM CN subsystem networks belonging to different security domains security procedures applies as described in TS 33.210 [20].

Annex L (normative):
Aspects for use of Common IMS in 3GPP2 systems