Configuring Quality Of Service; Quality Of Service (Qos) Overview; Cos To Queue Mapping Table Default Values - Dell PowerConnect 5316M User Manual

Configuring Quality of Service

This section provides information for defining and configuring Quality of Service (QoS)
parameters. To open the view, click Quality of Service in the tree view.

Quality of Service (QoS) Overview

Quality of Service (QoS) provides the ability to implement QoS and priority queuing within a
network.
An implementation example that requires QoS includes certain types of traffic such as Voice, Video
and real-time traffic, which can be assigned a high priority queue, while other traffic can be
assigned a lower priority queue. The result is an improved traffic flow for traffic with high demand.
QoS is defined by:
• Classification — Specifies which packet fields are matched to specific values. All packets
matching the user-defined specifications are classified together.
• Action — Defines traffic management where packets being forwarded are based on packet
information, and packet field values such as VLAN priority (VPT) and DSCP (DiffServ Code
Point).
VPT Tag Classification Information
VLAN Priority Tags are used to classify the packets by mapping packets to one of the egress queues.
VLAN Priority Tag to queue assignments are user-definable. The table below details the VPT to
queue default settings:
Table 9-86. CoS to Queue Mapping Table Default values
CoS Value
0
1
2
3
4
5
6
Forwarding Queue Values
q2 (Best Effort)
q1 (Lowest Priority)
q1 (Lowest Priority)
q2 ( Best Effort)
q3
q3
q4 (Highest Priority)
Configuring Quality of Service
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