In veins there are 4 Access Categories in CCH and 4 AC's in SCH. The static mapping between priority and AC is done in Mac1609_4::mapUserPriority() function.
How can we decide which priority to assign to a message(beacon-periodic/emergency-event/wsa-service) at application layer? Is there a standard that defines this priority assignment?. In the example that comes in veins, both beacon and WSM messages are assigned with a priority of 7.
I have seen some papers where they assign priority based on contents of the message. For a quick simulation, is it fine if we assign priorities like beacon (6), emergency (7) and wsa (5) or lower. Should Emergency messages given more priority than beacon messages? If we assign priorities like this, Are we actually using 4 AC queues here in this case?
The AC of a WaveShortMessage is determined by setting its userPriority value (see WaveShortMessage and BaseWaveApplLayer).