The ingress component of a network QoS policy defines the packet classification to internal forwarding class and profile state. The forwarding class and profile state define the Per Hop Behavior (PHB) or the QoS treatment through the router. The mapping defaults to that defined in the default network QoS policy until an explicit policy is defined for the network interface. Packets can also be redirected to an ingress FP queue group.
The egress component of a network QoS policy allows further egress classification to internal forwarding class and profile state. The egress of the network QoS policy also defines the marking based on the forwarding class and the profile state. Packets can also be redirected to an egress port queue group.
Network policy 1 is applied to all network interfaces by default. It cannot be modified or deleted. It defines the default DSCP-to-FC mapping and MPLS EXP-to-FC mapping for the ingress. For the egress, it defines eight forwarding classes and the packet marking criteria.
New (non-default) network policy parameters can be modified. A new network policy must include the definition of at least one queue and specify the default action. Incomplete network policies cannot be applied to network interfaces.
Changes made to a policy are applied immediately to all networks to which the policy is applied. For this reason, when a policy requires several changes, it is recommended to copy the policy to a work area policy-id. This work-in-progress copy can be modified until all the changes are made, then the original policy can be overwritten using the config qos copy command.