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QoS configuration approaches
Two approaches are available for configuring QoS:
Non-policy approach
Policy approach
Some features support both approaches, but some support only one.
Non-policy approach
In non-policy approach, you configure QoS service parameters directly without using a
QoS policy. For example, you can use the line rate feature to set a rate limit on an
interface without using a QoS policy.
Policy approach
In policy approach, you configure QoS service parameters by using QoS policies. A QoS
policy defines the shaping, policing, or other QoS actions to take on different classes of
traffic. It is a set of class-behavior associations.
A class is a set of match criteria for identifying traffic. It uses the AND or OR operator:
If the operator is AND, a packet must match all the criteria to match the class.
If the operator is OR, a packet matches the class if it matches any of the criteria in
the class.
A traffic behavior defines a set of QoS actions to take on packets, such as priority
marking and redirect.
By associating a traffic behavior with a class in a QoS policy, you apply the specific set
of QoS actions to the class of traffic.
Configuring a QoS policy
Figure 4
shows how to configure a QoS policy.
