G.12 MCPTT private emergency alert state

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

Table G.5-1provides the semantics of the MCPTT private emergency alert (MPEA) state values. This is an internal state of the MCPTT client and is managed by the MCPTT client. These states aid in the managing of the information elements of MCPTT emergency private calls and MCPTT emergency alerts and their cancellations. MCPTT private emergency alerts are targeted to an MCPTT user.

Table G.12-1: MCPTT private emergency alert state

MCPTT emergency alert state values

State-entering events


MPEA 1: no-alert

initial state

emergency alert cancelled

emergency alert request denied

emergency alerts targeted to an MCPTT user can be cancelled in several ways:

MCPTT emergency private call cancel request with <alert-ind> set to "false"

timeout of private call inactivity timer

end of call (if system policy)

MCPTT emergency state: may be set or clear, depending on MCPTT emergency call status

MPEA 2: emergency-alert-confirm-pending

emergency alert request sent

emergency alerts can be requested as an optional part of a MCPTT client’s request to initiate an MCPTT emergency private call, in which case the request has an <alert-ind> element set to "true".

MCPTT emergency state: is set

MPEA 3: emergency-alert -initiated

emergency alert response (success) received

MCPTT emergency state: is set

MPEA 4: emergency-alert-cancel-pending

emergency alert cancellation request sent by alert originator

MCPTT emergency state: is clear