3Com S7902E, Руководство по настройке

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3-3
For an MPLS packet, the priority mapping procedure as shown in Figure 3-2 is adopted:
Figure 3-2 Priority mapping procedure for an MPLS packet
Receive a
packet
Look up the
exp-dp table
Mark the packet
with drop
precedence
Look up the
exp-dot1p table
Mark the packet
with new 802.1p
priority
Look up the
dot1p-lp table
Mark the packet
with local
precedence
Schedule the packet
according to its local
precedence and drop
precedence
The priority mapping procedure presented above applies in the absence of priority marking. If priority
marking is configured, the device performs priority marking before priority mapping, and then uses the
re-marked packet-carried priority for priority mapping or directly uses the re-marked scheduling priority
for traffic scheduling depending on your configuration. In this case, neither priority trust mode
configuration on the port nor port priority configuration takes effect.
Priority Mapping Configuration Tasks
You are recommended to plan QoS throughout the network before making QoS configuration.
Complete the following task to configure priority mapping:
Task Remarks
Configuring a Priority Mapping Table Optional
Configuring the Priority Trust Mode on a Port Optional
Configuring the Port Priority of a Port Optional