35: QoS: VLAN 802.1Q PCP tagging
_______________________________________________________________________________________________________
_______________________________________________________________________________________________________
© Virtual Access 2018
GW1000 Series User Manual
Issue: 2.3
Page 363 of 463
Four queues are supported and are structured as follows:
•
Queue 1: PCP values 0 and 1 - Default
•
Queue 2: PCP values 2 and 3 - Normal
•
Queue 3: PCP values 4 and 5 - High
•
Queue 4: PCP values 6 and 7 - Express
Value 7 is the highest priority and 0 is the lowest. These queues prioritise 802.1Q tagged
frames as they are received on the port, these are hardware defined.
When 802.1Q frames are received on the port they are processed according to the above
queues on arrival (even if not defined in the configuration). Then if value
‘vlan_qos_map_ingress’ is configured you can modify the PCP priority for egress if the
frame was to be forwarded on another tagged interface.
When frames are received on an untagged VLAN interface configured with
‘vlan_qos_map_egress’ and are destined to tagged interface, 802.1Q tag will be created
with a default priority of 0 and then the priority will be set according to the PCP value
specified as the frames leave port.