ZyXEL Communications MES3500-24 User Manual

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MES3500-24/24F User’s Guide
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Classifier
This chapter introduces and shows you how to configure the packet classifier on the Switch.
20.1  About the Classifier and QoS
Quality of Service (QoS) refers to both a network's ability to deliver data with minimum delay, and 
the networking methods used to control the use of bandwidth. Without QoS, all traffic data is 
equally likely to be dropped when the network is congested. This can cause a reduction in network 
performance and make the network inadequate for time-critical application such as video-on-
demand.
A classifier groups traffic into data flows according to specific criteria such as the source address, 
destination address, source port number, destination port number or incoming port number. For 
example, you can configure a classifier to select traffic from the same protocol port (such as Telnet) 
to form a flow.
Configure QoS on the Switch to group and prioritize application traffic and fine-tune network 
performance. Setting up QoS involves two separate steps:
1
Configure classifiers to sort traffic into different flows. 
2
Configure policy rules to define actions to be performed for a classified traffic flow (refer to 
 
to configure policy rules).
20.2  Configuring the Classifier 
Use the Classifier screen to define the classifiers. After you define the classifier, you can specify 
actions (or policy) to act upon the traffic that matches the rules. To configure policy rules, refer to