6.3.3 MCPTT floor control procedures at MCPTT call release

24.3803GPPMission Critical Push To Talk (MCPTT) media plane controlProtocol specificationRelease 18TS

When an MCPTT client leaves an MCPTT call and the MCPTT call remains ongoing with the other MCPTT clients, the floor control server follows a two-step procedure.

Step 1 The MCPTT server stops sending floor control messages and RTP media packets to the MCPTT client leaving the MCPTT call and, the MCPTT server discards floor control messages and RTP media packets received from the MCPTT client leaving the MCPTT call.

Step 2 When the application and signalling plane has determined that the MCPTT call with this floor participant has been released, the corresponding instance of the floor control server state machine for ‘basic floor control operation towards the floor participant’ is released.

When an MCPTT call is released, the floor control server follows a two-step procedure.

Step 1 The MCPTT server stops sending floor control messages and RTP media packets to all floor participants in the MCPTT call.

Step 2 When the application and signalling plane has determined that the MCPTT call has been released, the corresponding instance of the floor control server state machine for ‘general floor control operation’ are also terminated, along with any ‘basic floor control operation towards the floor participant’ state machines for the floor participants of this call.

The floor control server state machine for general floor control operation initiates the MCPTT call release depending on the release policy specified in 3GPP TS 24.379 [2].