Network QoS policies in access-uplink mode

Network QoS policies define ingress FC meters and map traffic to the meters for access-uplink ports. A network QoS policy always has two meters/policers defined that cannot be deleted, one for the unicast traffic and one for multipoint traffic. These meters exist within the definition of the policy. The meters are instantiated in hardware only when the policy is applied to an access-uplink port. The policy also defines the FC-to-priority bit marking, on egress.

A network QoS policy defines both the ingress and egress handling of QoS on the access-uplink ports. The following functions are defined:

• Ingress

  • defines dot1p value mapping to FCs and profiles with an option to use the DEI bit along with dot1p classification (DSCP is not available for use)

  • defines FC to meter mapping

• Egress

  • option to define the FC to dot1p value and IP DSCP value for marking

  • remarking of QoS bits can be enabled or disabled

The following are the required elements defined in a network QoS policy:

• unique network QoS policy ID

• egress FC to dot1p value mappings for each FC

• default ingress FC and in-profile/out-of-profile state

• at least one default unicast FC meter. See Meter/policer parameters for information about the parameters that can be configured for a meter.

• at least one multipoint FC meter

Optional network QoS policy elements include the following:

• additional unicast meters up to a total of 8

• additional multipoint meters up to 8

• dot1p value to FC and profile state mappings for all dot1p values received

• option to use the DEI bit along with dot1p classification for profile state mapping

Network policy ID 1 is reserved as the default network QoS policy which cannot be deleted or changed. The default network QoS policy is applied to all access-uplink ports that do not have another network QoS policy assigned. The network QoS policy applied at network egress (for example, on an access-uplink port) determines how or whether the profile state is marked in packets transmitted into the service core network.

If the profile state is marked in the service core packets, out-of-profile packets are preferentially dropped over in-profile packets at congestion points in the core network. For network egress, traffic remarking in the network QoS policy is always enabled. The following table lists the default mapping of FC-to-dot1p values.

For network ingress, the following table lists the default mapping of dot1p values to FC and profile state for the default network QoS policy. Color-aware policing is supported on ingress for access-uplink ports.