Alcatel-Lucent 7950 Quality Of Service Manual page 270

Service Egress QoS Policy Forwarding Class Commands
A sap-egress policy differs from sap-ingress policies in the complexity of the QoS parameters that can be
defined. At ingress, policies determine queue mappings based on ingress DSCP, Dot1P and IP or MAC
match criteria. Multiple queues can be created per forwarding class and each queue can have different CIR
or PIR parameters.
At egress, the policies are much simpler, as the forwarding class and in or out of profile determination
happened way back at the original service ingress SAP. Egress SAP QoS policies allow the definition of
queues and the mapping of forwarding classes to those queues. Each queue needs to have a relative CIR for
determining its allocation of QoS resources during periods of congestion. A PIR can also be defined that
forces a hard limit on the packets transmitted through the queue. When the forwarding class is mapped to the
queue, a Dot1p value can optionally be specified. If specified and the SAP has a Dot1q encapsulation type,
the Dot1p value will be used for all packets that egress on that forwarding class. If the Dot1p value is not
specified, a Dot1p value of zero will be used. If the SAP is null encapsulated, or on a SONET/SDH
interface, the Dot1p value has no meaning.
A default-action parameter is required to specify the default queue used by all forwarding classes not
specifically mapped within the queue parameters. A sap-egress policy will be considered incomplete, if it
does not include definition of at least one queue and does not specify the default action. Incomplete sap-
egress policies cannot be applied to services.
The sap-egress policy with policy-id 1 is the default sap-egress QoS policy and is applied to service egress
SAPs when an explicit policy is not specified or removed. The system sap-egress policy can be modified but
not deleted. Using the no sap-egress command on policy-id 1 causes it to revert to its factory default
parameters.
The factory default settings for sap-egress policy-id 1 define a single queue with PIR set to the maximum
value and a CIR set to 25. The single queue is the default queue and all forwarding classes will map to it.
Packets being tagged according to the SAP encapsulation defined will have the Dot1p bits set to zero.
Any changes made to an existing policy, using any of the sub-commands, will be applied immediately to all
egress SAPs where this policy is applied. For this reason, when many changes are required on a policy, it is
highly recommended that the policy be copied to a work area policy-id. That work-in-progress policy can be
modified until complete and then written over the original policy-id. Use the config qos copy command to
maintain policies in this manner.
The no form of this command to deletes the sap-egress policy. A policy cannot be deleted until it is removed
from all service SAPs where it is applied. When a sap-egress policy is removed from a SAP, the SAP will
revert to the default sap-egress policy-id 1.
The system default sap-egress policy is a special case. The no command restores the factory defaults to
policy-id 1.
Parameters policy-id — The policy-id uniquely identifies the policy on the router.
Default
Values
policy-name — The policy-name uniquely identifies the policy.
Values
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none
1 — 65535
Valid names consist of any string up to 64 characters long. Policies must first be created
with a policy-id, after which a policy-name can be assigned and used as an alias to
reference the policy during configuration changes. Policy names may not begin with a
number (0-9) or the underscore "_" character (e.g. _myPolicy). "Default" or "default"
can not be used as policy names. Saved configurations and display output from the "info"
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