ZyXEL Communications VWG1312-B10A, User Manual

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Chapter 10 Quality of Service (QoS)
VMG1312-B10A User’s Guide
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10.6.1 Add/Edit a QoS Policer
Click Add new Policer in the Policer Setup screen or the Edit icon next to a policer to show the
following screen.
Figure 69
Policer Setup: Add/Edit
The following table describes the labels in this screen.
Table 47
Policer Setup: Add/Edit
LABEL DESCRIPTION
Active Select the check box to activate this policer.
Name Enter the descriptive name of this policer.
Meter Type This shows the traffic metering algorithm used in this policer.
The Simple Token Bucket algorithm uses tokens in a bucket to control when traffic can be
transmitted. Each token represents one byte. The algorithm allows bursts of up to b bytes
which is also the bucket size.
The Single Rate Three Color Marker (srTCM) is based on the token bucket filter and
identifies packets by comparing them to the Committed Information Rate (CIR), the
Committed Burst Size (CBS) and the Excess Burst Size (EBS).
The Two Rate Three Color Marker (trTCM) is based on the token bucket filter and
identifies packets by comparing them to the Committed Information Rate (CIR) and the
Peak Information Rate (PIR).
Committed
Rate Specify the committed rate. When the incoming traffic rate of the member QoS classes is
less than the committed rate, the device applies the conforming action to the traffic.
Committed
Burst Size Specify the committed burst size for packet bursts. This must be equal to or less than the
peak burst size (two rate three color) or excess burst size (single rate three color) if it is also
configured.
This is the maximum size of the (first) token bucket in a traffic metering algorithm.
Conforming
Action Specify what the Device does for packets within the committed rate and burst size (green-
marked packets).
• Pass: Send the packets without modification.
• DSCP Mark: Change the DSCP mark value of the packets. Enter the DSCP mark value to
use.
Non-
Conforming
Action Specify what the Device does for packets that exceed the excess burst size or peak rate and
burst size (red-marked packets).
• Drop: Discard the packets.
• DSCP Mark: Change the DSCP mark value of the packets. Enter the DSCP mark value to
use. The packets may be dropped if there is congestion on the network.