Chapter 20: Quality of Service (QoS) Commands

create qos policy=17 description=”video flow” trafficclasslist=19 ingressport=1

Policy 32 Commands:

create classifier=42 description=”video flow” ipdadddr=149.44.44.44

create qos flowgroup=36 description=”video flow” priority=4 classifierlist=42

create qos trafficclass=21 description=”video flow” maxbandwidth=5 flowgrouplist=36

create qos policy=32 description=”video flow” trafficclasslist=21 ingressport=8

The parts of the policies are:

Classifiers - Specify the IP address of the node with a video application. The classifier for Policy 17 specifies the address as a source address since this classifier is part of a policy concerning packets sent by the application. The classifier for Policy 32 specifies the address as a destination address since this classifier is part of a policy concerning packets going to the application.

Flow Groups - Specify the new priority level of 4 for the packets. As with the previous example, the packets leave the switch with the same priority level they had when they entered. The new priority level is relevant only while the packets traverse the switch. To alter the packets so that they leave containing the new level, you would change option 5, Remark Priority, to Yes.

Traffic Classes - Specify a maximum bandwidth of 5 Mbps for the packet stream. Bandwidth assignment can only be made at the traffic class level.

Policies - Specify the traffic class and the port where the policy is to be assigned.

Example 3: Critical Database

Critical databases typically require a high bandwidth. They also typically require less priority than either voice or video.

The policies in this example assign 50 Mbps bandwidth, with no change to priority, to traffic going to and from a database. The database is located on a node with the IP address 149.44.44.44 on port 1 of the switch.

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Allied Telesis management software layer 2+ fast ethernet switches manual Policy 32 Commands, Example 3 Critical Database