IP Multimedia (IM) Subsystem Sh interface; Signalling flows and message contents
This 3GPP Technical Specification (TS) specifies:
1. The interactions between the HSS (Home Subscriber Server) and the SIP AS (Application Server) and between the HSS and the OSA SCS (Service Capability Server). This interface is referred to as the Sh reference point.
2. The interactions between the SIP AS and the SLF (Subscription Locator Function) and between the OSA SCS and the SLF. This interface is referred to as the Dh reference point.
The IP Multimedia (IM) Core Network Subsystem stage 2 is specified in 3GPP TS 23.228 [1] and the signalling flows for the IP multimedia call control based on SIP and SDP are specified in 3GPP TS 24.228 [2].
The IP Multimedia (IM) Session Handling with the IP Multimedia (IM) call model is specified in 3GPP TS 23.218 [4].
This document addresses the signalling flows and message contents for the protocol at the Sh and Dh interface.
This document also addresses how the functionality of Ph interface is accomplished.
The Presence Service Stage 2 description (architecture and functional solution) is specified in 3GPP TS 23.141 [18].