3 Definitions, symbols and abbreviations

22.2793GPPCombined Circuit Switched (CS) and IP Multimedia Subsystem (IMS) sessionsStage 1TS

3.1 Definitions

For the purposes of the present document, the following terms and definitions apply:

Combinational Service: A combinational service is created by adding one or more IMS session(s) to a CS call (or vice versa). The CS call and IMS session are established between the same participants.

Combinational call: this is the name given to the service in which a circuit switched speech teleservice is enriched by adding an IMS session where both services (IMS session and CS call) are originated in one single UE and are terminated in another single UE.

Combinational Session: this is the name given to the service in which an ongoing IMS session between two users is enriched by adding a circuit switched based call. The individual service instances that form the combinational session are originated in a single UE and terminated in another single UE.

CSICS capable UE: UE that supports Combinational Service.

3.2 Abbreviations

For the purposes of the present document, the following abbreviations apply. Additional applicable abbreviations can be found in TR 21.905 [1].

CSICS Circuit Switched IMS Combinational Service