Alcatel-Lucent 7950 Quality Of Service Manual page 435

unknown-queue
Syntax
Context
Description
Parameters
cbs
Syntax
Context
Description
7950 XRS Quality of Service Guide
The multipoint keyword can be entered in the command line on a pre-existing multipoint queue
to edit queue-id parameters.
unknown-queue queue-id
no unknown-queue
config>qos>shared-queue>fc
This command configures the unknown unicast forwarding type queue mapping for fc fc-name. The
specified queue-id must exist within the policy as a multipoint queue before the mapping can be
made. Once the forwarding class mapping is executed, all unknown traffic on a SAP using this policy
is forwarded using the queue-id.
The unknown forwarding type usually tracks the multicast forwarding type definition. This command
overrides that default behavior.
The no form of this command sets the unknown forwarding type queue-id back to the default of track-
ing the multicast forwarding type queue mapping.
queue-id — The queue-id must be an existing, multipoint queue defined in the the config>qos>sap-
ingress context .
Values 25 — 32 .
cbs percent
no cbs
config>qos>shared-queue>queue
The Committed Burst Size (cbs) command specifies the relative amount of reserved buffers for a spe-
cific ingress network MDA forwarding class queue or egress network port forwarding class queue.
The value is entered as a percentage.
The CBS for a queue is used to determine whether it has exhausted its reserved buffers while enqueu-
ing packets. Once the queue has exceeded the amount of buffers considered in reserve for this queue,
it must contend with other queues for the available shared buffer space within the buffer pool. Access
to this shared pool space is controlled through Random Early Detection (RED) slope application.
Two RED slopes are maintained in each buffer pool. A high priority slope is used by in-profile pack-
ets. A low priority slope is used by out-of-profile packets. All Network-Control and Management
packets are considered in-profile. Assured packets are handled by their in-profile and out-of-profile
markings. All Best-Effort packets are considered out-of-profile. Premium queues should be config-
ured such that the CBS percent is sufficient to prevent shared buffering of packets. This is generally
taken care of by the CIR scheduling of Premium queues and the overall small amount of traffic on the
class. Premium queues in a properly designed system will drain before all others, limiting their buffer
utilization.
The RED slopes will detect congestion conditions and work to discard packets and slow down ran-
dom TCP session flows through the queue. The RED slope definitions can be defined, modified or
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