Priority mapping configuration, Priority mapping overview, Introduction to priority mapping – H3C Technologies H3C WX3000E Series Wireless Switches User Manual
Page 28: Introduction to priorities
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Priority mapping configuration
This chapter includes these sections:
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Priority mapping configuration tasks
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Displaying and maintaining priority mapping
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Priority mapping configuration examples
NOTE:
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The term "switch" or "device" in this chapter refers to the switching engine on a WX3000E
wired-wireless switch.
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The WX3000E series comprises WX3024E and WX3010E wired-wireless switches.
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The port numbers in this chapter are for illustration only.
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For information about packet precedences,
Appendix B Introduction to packet precedences
Priority mapping overview
Introduction to priority mapping
When a packet arrives, a device assigns a set of QoS priority parameters to the packet based on a
certain priority field carried in the packet or the port priority of the incoming port, depending on your
configuration. This process is called “priority mapping”. During this process, the device may modify the
priority of the packet depending on device status. The set of QoS priority parameters decides the
scheduling priority and forwarding priority of the packet.
Priority mapping is implemented with priority mapping tables and involves priorities such as 802.11e
priority, 802.1p priority, DSCP, EXP, IP precedence, local precedence, and drop precedence.
Introduction to priorities
Priorities fall into the following types: priorities carried in packets, and priorities locally assigned for
scheduling only.
The packet carried priorities include 802.1p priority, DSCP precedence, IP precedence, EXP, and so on.
These priorities have global significance and affect the forwarding priority of packets across the network.
For more information about these priorities, see the chapter “
The locally assigned priorities have only local significance. They are assigned by the device for
scheduling only. These priorities include the local precedence, drop precedence, and user precedence,
as follows.
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Local precedence is used for queuing. A local precedence value corresponds to an output queue.
A packet with higher local precedence is assigned to a higher priority output queue to be
preferentially scheduled.