Dell 34XX Computer Accessories User Manual


 
Configuring Quality of Service 373
Configuring Quality of Service
This section provides information for defining and configuring Quality of Service (QoS)
parameters. To open the
Quality of Service
page
,
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 tag (VPT) and DSCP (DiffServ
Code Point).
VPT 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 9-107. CoS to Queue Mapping Table Default values
CoS Value Forwarding Queue Values
0 q1 (Lowest Priority)
1 q1 (Lowest Priority)
2 q1(Lowest Priority)
3 q1 (Lowest Priority)
4q2
5q2
6q3
7q3