3Com 5500-EI PWR - Qos Configuration

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Table of Contents
1 QoS Configuration········································································································ 1-1
Overview ···················································································································· 1-1
Introduction to QoS ······························································································ 1-1
Traditional Packet Forwarding Service ·································································· 1-1
New Applications and New Requirements······························································ 1-1
Major Traffic Control Techniques ·········································································· 1-2
QoS Supported By Switch 5500-EI Series···································································· 1-3
Introduction to QoS Functions ····················································································· 1-4
Traffic Classification····························································································· 1-4
Priority Trust Mode ······························································································· 1-5
Protocol Priority ··································································································· 1-9
Priority Marking···································································································· 1-9
Traffic Policing ····································································································· 1-9
Line Rate ··········································································································· 1-11
Traffic Redirecting······························································································ 1-11
VLAN Mapping ··································································································· 1-11
Queue Scheduling ······························································································ 1-11
Congestion Avoidance ························································································ 1-14
Flow-based Traffic Accounting ············································································ 1-15
Burst·················································································································· 1-15
Traffic mirroring ································································································· 1-16
QoS Configuration ···································································································· 1-16
Configuring Priority Trust Mode ·········································································· 1-16
Configuring the Mapping between 802.1p Priority and Local Precedence·············· 1-17
Setting the Priority of Protocol Packets ······························································· 1-18
Marking Packet Priority······················································································· 1-19
Configuring Traffic Policing················································································· 1-20
Configuring Line Rate························································································· 1-22
Configuring Traffic Redirecting ··········································································· 1-22
Configuring VLAN Mapping················································································· 1-24
Configuring Queue Scheduling············································································ 1-24
Configuring WRED ····························································································· 1-26
Configuring Traffic Accounting············································································ 1-27
Enabling the Burst Function················································································ 1-28
Configuring Traffic Mirroring ··············································································· 1-28
Displaying and Maintaining QoS················································································ 1-30
QoS Configuration Examples ···················································································· 1-30
Configuration Example of Traffic policing and Line Rate ······································ 1-30
Configuration Example of Priority Marking and Queue Scheduling························ 1-31
VLAN Mapping Configuration Example ································································ 1-33
Configuring Traffic Mirroring and Redirecting Traffic to a Port······························ 1-36