21.4.1 General

29.0023GPPMobile Application Part (MAP) specificationRelease 17TS

The message flow for successful inter MSC group call / broadcast call set-up is shown in figure 21.4/1.

1) I_IAM (Note 1)

2) MAP_PREPARE_GROUP_CALL_req/ind

3) MAP_PREPARE_GROUP_CALL_rsp/cnf

4) I_IAM (Note 1)

5) MAP_SEND_GROUP_CALL_END_SIGNAL_req/ind

6) I_ACM (Note 1)

7) I_ACM (Note 1)

8) MAP_FORWARD_GROUP_CALL_SIGNALLING_req/ind (Note 2)

9) MAP_PROCESS_GROUP_CALL_SIGNALLING_req/ind (Note 2)

10) MAP_SEND_GROUP_CALL_END_SIGNAL_rsp/cnf

11) I_REL (Note 3)

12) I_REL (Note 3)

NOTE 1: TUP or ISUP may be used in signalling between MSCs, depending on the network type between the MSCs. For further details on the TUP and ISUP procedures refer to the following ITU-T Recommendations and ETSI specification:

– Q.721‑725 ‑ Telephone User Part (TUP);

– ETS 300 356-1 ‑ Integrated Services Digital Network (ISDN); Signalling System No.7; ISDN User Part (ISUP) version 2 for the international interface; Part 1: Basic services.

NOTE 2: The MAP_FORWARD_GROUP_CALL_SIGNALLING and MAP_PROCESS_GROUP_CALL_SIGNALLING services are not applicable for voice broadcast calls.

NOTE 3: The call can be released from the PSTN/ISDN or the Relay MSC

Figure 21.4/1: Message flow for inter MSC group call / broadcast call