SMC Networks 16 10BASE-T, 100BASE-TX manual Selecting the Queue Mode, Traffic Classes

Class of Service Configuration 3

Web – Click Priority, Traffic Classes. Mark an interface and click Select to display the current mapping of CoS values to output queues. Assign priorities to the traffic classes (i.e., output queues) for the selected interface, then click Apply.

Figure 3-73. Traffic Classes

CLI – The following example shows how to change the CoS assignments to a one-to-one mapping.

Console(config)#interface ethernet					1/1	4-104
Console(config-if)#queue				cos-map 0	0	4-166
Console(config-if)#queue				cos-map 1	1
Console(config-if)#queue				cos-map 2	2
Console(config-if)#end
Console#show queue		cos-map ethernet 1/1				4-168
Information of Eth		1/1	3	4 5 6 7
CoS Value	: 0	1 2
Priority Queue: 0		1 2	1	2 2 3 3
Console#

*Mapping specific values for CoS priorities is implemented as an interface configuration command, but any changes will apply to the all interfaces on the switch.

Selecting the Queue Mode

You can set the switch to service the queues based on a strict rule that requires all traffic in a higher priority queue to be processed before lower priority queues are serviced, or use Weighted Round-Robin (WRR) queuing that specifies a relative weight of each queue. WRR uses a predefined relative weight for each queue that determines the percentage of service time the switch services each queue before moving on to the next queue. This prevents the head-of-line blocking that can occur with strict priority queuing.

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