Allied Telesis AT-GS950/48, User Manual

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AT-GS950/48 Web Interface User Guide
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Egress Queue vs
Packet Priority
Mapping
Each port has four egress queues, labeled Low, Medium, High, Highest.
Low is the lowest priority queue and Highest is the highest. A packet in a
high-priority egress queue is typically transmitted sooner than a packet in
a low-priority queue.Table 2 lists the default mappings between the eight
CoS priority levels and the four egress queues of a switch port.
You can change these mappings. For example, you might decide that
packets with a priority of 6 and 7 need to be handled by egress queue
Highest and packets with a priority of 2 and 3 should be handled in
Medium. The result is shown in Table 3.
Table 2. Default Mappings Priority Levels to Priority Queues
IEEE 802.1p
Priority Level
Port Priority
Queue
0 Low
1 Low
2 Low
3 Low
4 Low
5 Low
6 Low
7 Low
Table 3. Customized Mappings Priority Levels to Priority Queues
IEEE 802.1p
Priority Level
Port Priority
Queue
0 Low
1 Low
2 Medium
3 Medium
4 High
5 High
6 Highest
7 Highest