Quality Of Service Overview; Defining Qos Basic Mode - 3Com 3CRUS2475 User Manual

Quality of Service
Overview
Defining QoS Basic
Mode
Quality of Service (QoS) provides the ability to implement QoS and priority
queuing within a network. For example, certain types of traffic that
require minimal delay, such as Voice, Video, and real-time traffic 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
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values. All packets matching the user-defined specifications are
classified together.
Action — Defines traffic management where packets are forwarded
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are based on packet information, and packet field values such as
VLAN Priority Tag (VPT) and DiffServ Code Point (DSCP).
VPT Classification Information
VLAN Priority Tags (VPT) are used to classify packets by mapping packets
to one of the egress queues. VPT-to-queue assignments are
user-definable. Packets arriving untagged are assigned a default VPT
value, which is set on a per-port basis. The assigned VPT is used to map
the packet to the egress queue.
This section contains information for defining QoS basic settings and
includes the following topics:
Configuring Trust Settings
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Configure DSCP Rewrite
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Quality of Service Overview

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