Class of Service Configuration 3

Mapping CoS Values to Egress Queues

This switch processes Class of Service (CoS) priority tagged traffic by using eight priority queues for each port, with service schedules based on strict or Weighted Round Robin (WRR). Up to eight separate traffic priorities are defined in IEEE 802.1p. The default priority levels are assigned according to recommendations in the IEEE 802.1p standard as shown in the following table.

Table 3-12 Mapping CoS Values to Egress Queues

Queue

0

1

2

3

4

5

6

7

 

 

 

 

 

 

 

 

 

Priority

2

0

1

3

4

5

6

7

 

 

 

 

 

 

 

 

 

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 way that benefits application traffic for your own network.

 

Table 3-13 CoS Priority Levels

Priority Level

Traffic Type

 

 

1

Background

 

 

2

(Spare)

 

 

0 (default)

Best Effort

 

 

3

Excellent Effort

 

 

4

Controlled Load

 

 

5

Video, less than 100 milliseconds latency and jitter

 

 

6

Voice, less than 10 milliseconds latency and jitter

 

 

7

Network Control

 

 

Command Attributes

•Priority – CoS value. (Range: 0-7, where 7 is the highest priority)

•Traffic Class21 – Output queue buffer. (Range: 0-7, where 7 is the highest CoS priority queue)

21. CLI shows Queue ID.

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