Allied Telesis AT-S62 - Manual (Page 292)

Chapter 17: Quality of Service (QoS) Commands
292 Section II: Advanced Operations
ˆ Traffic Classes - No action is taken by the traffic classes, other than to
specify the flow groups. Traffic class has a priority setting that can be
used to override the priority level of packets, just as in a flow group. If
you enter a priority value both in the flow group and the traffic class,
the value in the flow group overrides the value in the traffic class.
ˆ Policies - Specify the traffic class and the port to which the policy is to
be assigned. Policy 6 is applied to port 1 since this is where the
application is located. Policy 11 is applied to port 8 since this is where
traffic going to the application will be received on the switch.
Example 2: Video Application
Video applications typically require a larger bandwidth than voice
applications. Video applications can be set up to have a high priority and
buffering, depending on the application.
This example creates policies with low latency and jitter for video streams
(for example, net conference calls). The policies assign the packets a
priority level of 4. The policies also limit the bandwidth for the video
streams to 5 Mbps to illustrate how you can combine a change to the
priority level with bandwidth restriction to further define traffic control. The
node containing the application has the IP address 149.44.44.44. Policy
17 is assigned to port 1, where the application is located, and Policy 32 is
assigned to port 8 where packets destined to the application enter the
switch.
Policy 17 Commands:
create classifier=16 description=”video flow”
ipsadddr=149.44.44.44
create qos flowgroup=41 description=”video flow”
priority=4 classifierlist=16
create qos trafficclass=19 description=”video flow”
maxbandwidth=5 flowgrouplist=41
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