A.2 Introduction

24.3373GPPIP Multimedia (IM) Core Network (CN) subsystem IP Multimedia Subsystem (IMS) inter-UE transferRelease 17Stage 3TS

A.2.1 General

The signalling flows provided in this annex follow the methodology developed in 3GPP TS 24.228 [6].

A.2.2 Key required to interpret signalling flows

The key to interpret signalling flows specified in 3GPP TS 24.228 [6] subclauses 4.1 and 4.2 applies with the additions specified below:

– tel:+1-237-555-1111 represents the public user indentity of SC UE A.

– tel:+1-237-555-2222 represents the public user indentity of UE B.

– sip:sccas1.home1.net represents the Internet host of SCC AS.

– sip:interUEtransfer@sccas1.home1.net represents the Inter UE Transfer SCC AS URI of the UA A.

Each signalling flow table contains descriptions for headers where the content of the header is new to that signalling flow, as is already performed in 3GPP TS 24.228 [6].

However, 3GPP TS 24.228 [6] includes extensive descriptions for the contents of various headers following each of the tables representing the contents of the signalling flows. Where the operation of the header is identical to that shown in 3GPP TS 24.228 [6], then such text is not reproduced in the present document.

Additional text may also be found on the contents of headers within 3GPP TS 24.228 [6] in addition to the material shown in the present document.

In order to differentiate between messages for SIP and media, the notation in figure A.2-1 is used.

Figure A.2-1: Signalling flow notation