ETSI - TS 124 093
Digital cellular telecommunications system (Phase 2+) (GSM); Universal Mobile Telecommunications System (UMTS); Completion of Calls to Busy Subscriber (CCBS); Stage 3
|Publication Date:||1 July 2020|
The present dcoument gives the stage 3 description of the Completion of Calls to Busy Subscriber (CCBS) supplementary service. The present document specifies the procedures used at the radio interface (Reference point Um as defined in 3GPP TS 24.002) for normal operation, activation, deactivation, invocation and interrogation of the completion of calls to busy subscriber supplementary services. Provision and withdrawal of supplementary services is an administrative matter between the mobile subscriber and the service provider and cause no signalling on the radio interface.
In 3GPP TS 24.010 the general aspects of the specification of supplementary services at the layer 3 radio interface are given.
3GPP TS 24.080 specifies the formats and coding for the supplementary services.
Definitions and descriptions of supplementary services are given in 3GPP TS 22.004, 3GPP TS 22.08x and 3GPP TS 22.09x-series. Technical specification 3GPP TS 22.093 is related specifically to the Completion of Calls to Busy Subscriber supplementary service.
The technical realization of supplementary services is described in technical specifications 3GPP TS 23.011, 3GPP TS 23.08x and 3GPP TS 23.09x-series. 3GPP TS 23.093 is related specifically to Completion of Calls to Busy Subscriber supplementary service.
The procedures for Call Control, Mobility Management and Radio Resource management at the layer 3 radio interface are defined in 3GPP TS 24.007 and 3GPP TS 24.008.
The following supplementary services belong to the call completion supplementary services and are described in the present document:
- Completion of Calls to Busy Subscriber (CCBS) (see clause 4).