1
Scope
2
References
3
Definitions
3.1
Terms defined elsewhere
3.2
Terms defined within this Recommendation
4
Abbreviations and acronyms
5
Conventions
6
Service architecture
6.1
General architecture
6.2
Functional entities involved in IP Centrex service
7
Signalling requirements
7.1
General description
7.2
Signalling requirements
8
Protocol profiles
9
Security considerations
Appendix I – IMS-based signalling flows for the IP Centrex service
I.1
Internal communication
I.2
Outgoing communication
I.3
Incoming communication
I.4
Originating identification presentation
I.5
Originating identification restriction
I.6
Terminating identification presentation
I.7
Terminating identification restriction
I.8
Communication transfer
I.9
Communication diversion
I.10
Communication pickup
I.11
Communication hold
Appendix II – Call server based signalling flows for the IP Centrex
service
Bibliography