H3C Technologies H3C WX3000E Series Wireless Switches - Manual (Page 30)

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Configuring priority mapping
Overview
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, and local 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, 802.11e priority, 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 "Appendix."
The locally assigned priorities have only local significance. They are assigned by the device for
scheduling only. These priorities include the local precedence.
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.
Priority mapping tables
The device provides various types of priority mapping tables, or rather, priority mappings. By looking up
a priority mapping table, the device decides which priority value is to assign to a packet for subsequent
packet processing.
The default priority mapping tables are available for priority mapping. They are adequate in most cases.
If a default priority mapping table cannot meet your requirements, you can modify the priority mapping
table as required.
The default priority mapping tables are as follows:
NOTE:
For the default dot11e-lp priority mapping table, an input value yields a target value that is equal to it.