CONTENTS

1 Scope
2 References
3 Terms and definitions
4 Abbreviations and acronyms
5 SS-CI service description
5.1 Implementation options
5.2 Provision of capability and protection levels
5.3 Normal procedures
5.3.1 Activation/deactivation/registration/interrogation
5.3.2 Invocation and operation
5.3.3 Exceptional procedures
5.4 Interactions with other supplementary services
5.4.1 Call Transfer (SS-CT)
5.4.2 Call Forwarding Unconditional (SS-CFU)
5.4.3 Call Forwarding Busy (SS-CFB)
5.4.4 Call Forwarding on No Reply (SS-CFNR)/Call Deflection (SS-CD)
5.4.5 Call Hold
5.4.6 Call Park/Call Pickup
5.4.7 Call Waiting
5.4.8 Message Waiting Indication
5.4.9 Name Presentation
5.4.10 Completion of Calls to Busy Subscriber (SS-CCBS)
5.4.11 Completion of Calls on No Reply (SS-CCNR)
5.4.12 Call Offer (SS-CO)
5.4.13 Common information
5.4.14 Call Linkage
6 Messages and information elements
7 Signalling procedures
7.1 Actions at user A's endpoint
7.1.1 Procedure for initial invocation of SS-CI
7.1.2 Optional procedure for invocation of isolation
7.1.3 Optional procedure for invocation of forced release
7.1.4 Optional procedure for invocation of wait-on-busy
7.1.5 Optional procedure for (re-)invocation of SS-CI on a waiting call
7.1.6 Procedure for completion of SS-CI
7.2 Actions at user B's endpoint
7.2.1 Procedure for invocation of SS-CI
7.2.2 Optional procedures for invocation of isolation
7.2.3 Optional procedures for invocation of forced release
7.2.4 Optional procedures for wait-on-busy (WOB)
7.2.5 Procedures for completion of SS-CI
7.3 Actions at user C's endpoint
8 Interworking and interactions
8.1 Interworking with SCN
8.2 Protocol interaction between SS-CI and other supplementary services
8.2.1 Call Transfer (SS-CT)
8.2.2 Call Forwarding Unconditional (SS-CFU)
8.2.3 Call Forwarding Busy (SS-CFB)
8.2.4 Call Forwarding on No Reply (SS-CFNR)/Call Deflection (SS-CD)
8.2.5 Call Hold
8.2.6 Call Park/Call Pickup
8.2.7 Call Waiting
8.2.8 Message Waiting Indication
8.2.9 Name Presentation
8.2.10 Completion of Calls to Busy Subscriber (SS-CCBS)/on No Reply (SS-CCNR)
8.2.11 Call Offer (SS-CO)
8.2.12 Common Information
8.2.13 Call Linkage
9 Gatekeeper/Proxy actions
9.1 Gatekeeper passes on SS-CI operations to the endpoint
9.2 Gatekeeper/proxy acts on behalf of an endpoint
9.2.1 Gatekeeper/proxy acts on behalf of endpoint A
9.2.2 Gatekeeper/proxy acts on behalf of endpoint B
9.2.3 Gatekeeper/proxy acts on behalf of endpoint C
10 Dynamic description
10.1 Operational model
10.2 Signalling flows
10.2.1 Successful SS-CI - direct call signalling
10.2.2 Unsuccessful SS-CI
10.2.3 Successful SS-CI GK routed call signalling
10.3 Communication between an endpoint A signalling entity (EASE) and its Signalling entity user (for information purposes)
10.3.1 Table of primitives
10.3.2 Primitive definition
10.3.3 Parameter definition
10.4 Communication between an endpoint B signalling entity (EBSE) and its signalling entity user (for information purposes)
10.4.1 Table of primitives
10.4.2 Primitive definition
10.4.3 Parameter definition
10.5 Communication between an endpoint C signalling entity (ECSE) and its signalling entity user (for information purposes)
10.5.1 Table of primitives
10.5.2 Primitive definition
10.5.3 Parameter definition
10.6 Call states
10.6.1 Call states at endpoint A
10.6.2 Call states at endpoint B
10.6.3 Call states at endpoint C
10.7 Timers
10.7.1 Timers at endpoint A
10.7.2 Timers at endpoint B
11 Operations in support of Call Intrusion supplementary service
12 Specification and description language (SDL) diagrams for SS-CI
12.1 Behaviour of user A's endpoint
12.2 Behaviour of user B's endpoint
12.3 Behaviour of user C's endpoint