A.2 Introduction

24.2473GPPMessaging service using the IP Multimedia (IM) Core Network (CN) subsystemRelease 17Stage 3TS

A.2.1 General

A.2.2 Key required to interpret signalling flows

The key to interpret signalling flows specified in 3GPP TS 24.228 [4] clause 4.1 applies with the additions specified below :

– #### represents the contents in the headers are not shown and does not impact the implementation of the flows.

In order to differentiate between messages for SIP and MSRP, the following notation is used:

Figure A.2.2-1: Signalling flow notation