User guide

QOS QoS implementation for DIFFSERV
iMG/RG Software Reference Manual (Quality of Service)
7-4
The Drop priority is used by the Algorithmic dropper component of the Schedule, which when configured
drops packets selectively during a congestion condition in Scheduler queues. The packets with a higher drop
priority have a higher probability of getting dropped than lower priority packets.
The Classifier initially sets the drop priority, and then the drop priority may optionally be modified by the Meter
device if the packet is out of profile. The Meter will then communicate the drop priority to the Scheduler
device.
Both the Classifier and Meter devices can set the drop priority. The Classifier device sets the drop priority con-
figured in the classification rule while the Meter device sets the drop priority depending upon the metering
result.
Note: If both the Classifier and the Meter are configured, then the Meter overwrites the drop priority value that
the Classifier has set.
7.1.3.2.1 Configuring the Classifier
This section explains the basic steps to follow in order to configure the Classifier. It does not include details
about the function of each command. See the section at the end of the currect section for a detailed descrip-
tion of each classifier command. To configure the Classifier, use the following CLI commands:
1. Create a profile using the command CLASSIFIER ADD PROFILE.
2. Add one or more rules to the profile using the command CLASSIFIER PROFILE ADD RULE
3. Configure the rule, using one the following commands:
CLASSIFIER PROFILE SET RULE DROPPRIO
CLASSIFIER PROFILE SET RULE DSCP
CLASSIFIER PROFILE SET RULE DSTADDR
CLASSIFIER PROFILE SET RULE DSTPORT
CLASSIFIER PROFILE SET RULE MARK DSCP
CLASSIFIER PROFILE SET RULE METERID
CLASSIFIER PROFILE SET RULE PRIORITY
CLASSIFIER PROFILE SET RULE PROTOCOL
CLASSIFIER PROFILE SET RULE SRCADDR
CLASSIFIER PROFILE SET RULE SRCPORT
CLASSIFIER PROFILE SET RULE TOS
Note: Note that the classifier can be assigned only on the ethernet transport named default
The rule value or values will vary, depending on which packet fields you want to test. For example, to configure
a rule to test the source IP address of incoming packets, use the command: