G.10 MCPTT emergency private priority state

24.3793GPPMission Critical Push To Talk (MCPTT) call controlProtocol specificationRelease 18TS

Tools: ARFCN - Frequency Conversion for 5G NR/LTE/UMTS/GSM

The MCPTT emergency private priority state is the MCPTT client’s perspective of the in-progress emergency private call state which is managed by the controlling MCPTT function. The MCPTT emergency private priority (MEPP) state is managed by the MCPTT client to enable the requesting of MCPTT emergency-level priority as early as possible in the origination of an MCPTT emergency private call. High-level characteristics of this state are captured in table G.10-1.

Table G.10-1: MCPTT emergency private priority state

MCPTT emergency private priority state values	State-entering events	Comments
MEPP 1: no-emergency	initial state prior to any call activity Emergency private call cancel request received on behalf of another user from the MCPTT server Emergency private call cancel response (success) in response to initiator’s request
MEPP 2: in-progress	Emergency private call response received (confirm) to initiator’s emergency private call request Emergency private call request received (on behalf of another user)	In this state, both participants in calls to each other will request emergency level priority whether or not they are in the MCPTT emergency state themselves.
MEPP 3: cancel-pending	Emergency private call cancel request sent by initiator	The controlling MCPTT server may not grant the cancel request for various reasons, e.g., the other user in the call is in an MCPTT emergency state.
MEPP 4: confirm-pending	Emergency private call request sent by initiator	The controlling MCPTT server may not grant the call request for various reasons, e.g., the MCPTT user is not configured as being authorised to originate an emergency private call so it can’t be assumed that the call (originator and target users) will enter the in-progress state.