Alcatel-Lucent 7450 Quality Of Service Manual page 247

high — This parameter is used in conjunction with the priority parameter. Setting the enqueuing
low — This parameter is used in conjunction with the priority parameter. Setting the enqueuing
dscp
Syntax dscp dscp-name [dscp-name...(up to 8 max)] [fc fc-name] [hsmda-counter-override
counter-id] [profile {in | out}]
no dscp dscp-name [dscp-name...(up to 8 max)]
Context config>qos>sap-egress
Description This command defines IP Differentiated Services Code Point (DSCP) names that must be matched to
perform the associated reclassification actions. The specified name must exist as a dscp-name. SR OS
software provides names for the well-known code points. A list of up to 8 dscp-names can be entered
on a single command. The lists of dscp-names within the configuration are managed by the system to
ensure that each list does not exceed 8 names. Entering more than 8 dscp-names with the same
parameters (fc, hsmda-counter-override, priority) will result in multiple lists being created.
Conversely, multiple lists with the same parameters (fc, hsmda-counter-override, priority) are merged
and the lists repacked to a maximum of 8 per list if dscp-names are removed or the parameters changed
so the multiple lists use the same parameters. Also, if a subset of a list is entered with different
parameters then a new list will be created for the subset. When the list is stored in the configuration,
the dscp-names are sorted by their DSCP value in ascending numerical order, consequently the order
in the configuration may not be exactly what the user entered.
If an egress packet on the SAP matches an IP DSCP value corresponding to a specified dscp-name, the
forwarding class, profile or HSMDA egress queue accounting behavior may be overridden. By default,
the forwarding class and profile of the packet is derived from ingress classification and profiling
functions. The default behavior for HSMDA queue accounting is to use the counters associated with
the queue to which the packet is mapped. Matching a DSCP based reclassification rule will override
all IP precedence based reclassification rule actions.
The IP DSCP bits used to match against dscp reclassification rules come from the Type of Service
(ToS) field within the IPv4 header or the Traffic Class field from the IPv6 header. If the packet does
not have an IP header, dscp based matching is not performed.
Quality of Service Guide
parameter to high for a packet increases the likelihood of enqueuing the packet when the
ingress queue is congested. Ingress enqueuing priority only affects ingress SAP queuing.
Once the packet is placed in a buffer on the ingress queue, the significance of the enqueuing
priority is lost.
Default
low priority
parameter to low for a packet decreases the likelihood of enqueuing the packet when the
ingress queue is congested. Ingress enqueuing priority only affects ingress SAP queuing, once
the packet is placed in a buffer on the ingress queue, the significance of the enqueuing priority
is lost.
Default Inherit (When priority is not defined, the rule preserves the
previous enqueuing priority of the packet.)
Service Egress and Ingress QoS Policies
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