10.4 MCPTT group selection
23.3793GPPFunctional architecture and information flows to support Mission Critical Push To Talk (MCPTT)Release 18Stage 2TS
10.4.1 General
When an MCPTT user wants to transmit on a MCPTT group, an affiliated MCPTT group shall be set as the selected MCPTT group to the MCPTT user. Only one MCPTT group can be set as the selected MCPTT group to an MCPTT user from one particular MCPTT UE at any given time. This subclause describes the detailed procedures for the MCPTT group selection.
10.4.2 Information flows for group selection
10.4.2.1 Group selection change request
Table 10.4.2.1-1 describes the information flow group selection change request from the MCPTT client to the MCPTT server.
Table 10.4.2.1-1: Group selection change request
|
Information element |
Status |
Description |
|
MCPTT ID |
M |
MCPTT user identity whose group selection information is to be changed |
|
MCPTT group ID |
M |
MCPTT group identity for which the selection is made for the MCPTT ID |
10.4.2.2 Group selection change response
Table 10.4.2.2-1 describes the information flow group selection change response from the MCPTT server to the MCPTT client.
Table 10.4.2.2-1: Group selection change response
|
Information element |
Status |
Description |
|
Result |
M |
Result indicates success or failure of group selection change |
10.4.2.3 Group selection change notification
Table 10.4.2.3-1 describes the information flow group selection change notification from the MCPTT server to the MCPTT client.
Table 10.4.2.3-1: Group selection change notification
|
Information element |
Status |
Description |
|
MCPTT ID |
M |
MCPTT user identity whose group selection information is to be changed |
|
MCPTT group ID |
M |
MCPTT group identity for which the selection is made for the MCPTT ID |
10.4.3 Authorized user remotely changes another MCPTT user’s selected MCPTT group – mandatory mode
Procedure for an authorized user to change other MCPTT users’ selected MCPTT group without requiring target user’s approval is described in figure 10.4.3-1.
Pre-conditions:
– The MCPTT client 1 has already been provisioned (statically or dynamically) with the target MCPTT user’s information and its group information, that the selected MCPTT group of target MCPTT user 2 is allowed to be changed;
Figure 10.4.3-1: Remotely change MCPTT group selection – mandatory mode
1. When an authorized user changes other MCPTT users’ selected MCPTT group, the MCPTT client 1 sends MCPTT group selection change request to the MCPTT server. The information (i.e. target MCPTT ID, MCPTT group ID) used to set the requested MCPTT group as the selected MCPTT group of the target MCPTT user shall be included.
2. The MCPTT server shall check if the MCPTT user 1 is authorized to change the target MCPTT user’s selected MCPTT group. The MCPTT server shall perform the affiliation relationship check based on the stored affiliation status.
3. If the MCPTT user 1 is authorized to change the target MCPTT user’s selected MCPTT group, and if the target MCPTT user is not already affiliated to the requested MCPTT group, the remotely change of affiliation procedures shall be performed (see subclause 10.8 in 3GPP TS 23.280 [16]).
4. The MCPTT server then shall send the MCPTT group selection change notification including the target user ID and the selected MCPTT group ID to the MCPTT client 2.
5. The group selection change response then returns to the MCPTT client 1.
6. Target MCPTT client 2 are notified about the change of its selected MCPTT group.