4.1 Architecture

23.2783GPPCustomised Applications for Mobile network Enhanced Logic (CAMEL) Phase 4IM CN InterworkingRelease 17Stage 2TS

This clause describes the functional architecture needed to support CAMEL interactions with the S‑CSCF in the IP Multimedia Subsystem. The IM‑SSF is a SIP Application Server that interfaces SIP to CAP. The generic SIP Application Server behaviour of the IM‑SSF is specified in 3GPP TS 23.218 [5].

4.1.1 Functional Entities used for CAMEL at IP Multimedia Registration

Figure 4.1 shows the functional entities involved when an MS registers for IP Multimedia session requiring CAMEL support. General registration procedure is detailed in 3GPP TS 23.228 [6]. Upon notification of a UE’s registration, the IM‑SSF requests O‑IM‑CSI, D‑IM‑CSI, VT‑IM‑CSI data from the HSS over the Si interface.

Figure 4.1: Functional architecture for support of CAMEL when mobile registers for IP Multimedia session

4.1.2 Functional Entities used for CAMEL for MO and MT IP Multimedia session

Figure 4.2 shows the functional entities involved in a Mobile Originated IP Multimedia session requiring CAMEL support. The same functional architecture applies in a Mobile Terminated IP Multimedia session for CAMEL.

Figure 4.2: Functional architecture for support of CAMEL control of a MO IP Multimedia session