Configuring the Switch
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3
Mapping CoS Values to Egress Queues
This switch processes Class of Service (CoS) priority tagged traffic by using four
priority queues for each port, with service schedules based on strict or Weigh ted
Round Robin (WRR). Up to eight separate traffic priorities are defined in IEEE
802.1p. The default priority levels are assigned according to recomme ndations in
the IEEE 802.1p standard as shown in the following table.
The priority levels recommended in the IEEE 802.1p standard for various network
applications are shown in the following table. However, you can map the priority
levels to the switch’s output queues in any wa y that benefits application traffic for
your own network.
Command Attributes
•Priority – CoS value. (Range: 0-7, where 7 is the highest priority)
•Traffic Class* – Output queue buffer. (Range: 0-3, where 3 is the highest CoS
priority queue)
* CLI shows Queue ID.
Table 3-10. Egress Queue Priority Mapping
Queue 0123
Priority 1,20,34,56,7
Table 3-11. Priority Level Descriptions
Priority Level Traffic Type
1 Background
2(Spare)
0 (default) Best Effort
3 Excellent Effort
4 Controlled Load
5 Video, less than 100 milliseco nds latency and jitter
6 Voice, less than 10 milliseconds l atency and jitter
7 Network Control
Q0
Serviced
byweighted
roundrobin
Q1
Q2
Q3
1,2
0,3
4,5
6,7