GSM 09.02 - Version 5.3.0 - Digital cellular telecommunications - ETSI

Page 132
GSM 09.02 version 5.3.0: August 1996
9.6 MAP_INVOKE_SS service
9.6.1 Definitions
This service is used between the MSC and the VLR to check the subscriber's subscription to a given
supplementary service in the VLR, in connection with in-call invocation of that supplementary service, i.e.
after the call set-up phase is finished. For supplementary service invocation during call set-up phase,
please refer to the call handling descriptions.
The service is a confirmed service and consists of four service primitives.
9.6.2 Service primitives
The service primitives are shown in table 9.6/1.
9.6.3 Parameter use
Invoke id
Parameter name Request Indication Response Confirm
Invoke id M M(=) M(=) M(=)
SS-Code M M(=)
Basic service C C(=)
User error C C(=)
Provider error O
See subclause 5.6.1 for the use of this parameter.
SS-Code
Table 9.6/1: MAP_INVOKE_SS parameters
This SS-Code can only refer to a single supplementary service, e.g. the Call Hold or Multi Party
supplementary services.
Basic service
This parameter indicates for which basic service the supplementary service invocation is required.
User error
This parameter is sent by the responder upon unsuccessful outcome of the service, and then takes one of
the following values:
- System Failure;
- Data Missing;
- Unexpected data value;
- Call Barred;
- Illegal SS operation;
- SS error status;
- SS not available.
Provider error
See subclause 5.6.1 for the use of this parameter.