Specifications

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Cisco MWR 2941 Mobile Wireless Edge Router Software Configuration Guide, Release 12.2(33)MRB
OL-21227-02
Appendix B Cisco MWR 2941 Router Command Reference
class (policy-map)
Usage Guidelines Policy Map Configuration Mode
Within a policy map, the class (policy-map) command can be used to specify the name of the class whose
policy you want to create or change. First, the policy map must be identified.
To identify the policy map (and enter the required policy-map configuration mode), use the policy-map
command before you use the class (policy-map) command. After you specify a policy map, you can
configure policy for new classes or modify the policy for any existing classes in that policy map.
Class Characteristics
The class name that you specify in the policy map ties the characteristics for that class—that is, its
policy—to the class map and its match criteria, as configured using the class-map command.
When you configure policy for a class and specify its bandwidth and attach the policy map to an
interface, class-based weighted fair queueing (CBWFQ) determines if the bandwidth requirement of the
class can be satisfied. If so, CBWFQ allocates a queue for the bandwidth requirement.
When a class is removed, available bandwidth for the interface is incremented by the amount previously
allocated to the class.
The maximum number of classes that you can configure for a router—and, therefore, within a policy
map—is 64.
Predefined Default Class
The class-default keyword is used to specify the predefined default class called class-default. The
class-default class is the class to which traffic is directed if that traffic does not match any of the match
criteria in the configured class maps.
Tail Drop or WRED
You can define a class policy to use either tail drop by using the queue-limit command or Weighted
Random Early Detection (WRED) by using the random-detect command. When using either tail drop
or WRED, note the following points:
• The queue-limit and random-detect commands cannot be used in the same class policy, but they
can be used in two class policies in the same policy map.
• You can configure the bandwidth command when either the queue-limit command or the
random-detect command is configured in a class policy. The bandwidth command specifies the
amount of bandwidth allocated for the class.
• For the predefined default class, you can configure the fair-queue (class-default) command. The
fair-queue command specifies the number of dynamic queues for the default class. The fair-queue
command can be used in the same class policy as either the queue-limit command or the
random-detect command. It cannot be used with the bandwidth command.
12.4(20)MR This command was integrated into Cisco IOS Release 12.4(20)MR. This
release does not support the fragment, insert-before, or service-fragment
parameters.
12.2(33)MRA This command was integrated into Cisco IOS Release 12.2(33)MRA. This
release does not support the fragment, insert-before, or service-fragment
parameters.
Release Modification