Nortel 4524GT Configuration page 33

The valid precedence range can change if certain features are enabled.
QoS shares resources with other switch applications such as MAC Security
and Port Mirroring. Allocations for non-QoS applications are dynamic. The
following list describes how the precedence range is affected by enabling
these features:
•
•
A policy can reference an individual classifier or a classifier block.
A policy is a network traffic-controlling mechanism that monitors the
characteristics of the traffic (for example, its source, destination, and
protocol), and performs a controlling action on the traffic when certain
user-defined characteristics are matched. A policy action is the effect a
policy has on network traffic that matches the traffic profile of the policy.
The policies tie together:
•
•
•
•
The policies, by connecting these user-defined configurations, control the
traffic on the switch.
Ports can be assigned to interface groups that are linked to policies.
Port-based policies eliminate the need to create an interface group for a
single port, and are used to directly apply a policy to a single port.
Although a single policy can reference only one interface group, you can
configure several policies that reference the same interface group. The
policies determine the traffic treatment of the flows.
Policies can be enabled and disabled. Policies do not have to be deleted to be
disabled. To modify a policy, it must first be deleted and a new policy created.
Statistics can also be tracked for QoS. The Nortel Ethernet Routing Switch
4500 Series supports statistics for each policy and for each policy, classifier,
or interface statistics tracking.
Copyright © 2007, Nortel Networks
.
When MAC Security is enabled, it uses the highest available
precedence value.
When Port Mirroring is enabled using one of the following modes:
Asrc, Adst, AsrcBdst, AsrcBdstOrBsrcAdst, AsrcOrAdst,
XrxYtxOrYrxXtx, XrxYtx, and the highest available precedence will
be used by Port-Mirroring.
Actions
Meters
Classifier elements or classifiers or classifier blocks
Interface groups
Nortel Ethernet Routing Switch 4500 Series
Configuration — Quality of Service
NN47205-504 (322816-B)
5.1 23 November 2007
ATTENTION
03.01 Standard
Specifying policies 33