422
 Trust port priority—The device assigns a priority to a packet by mapping the priority of the receiving
port.
You can select one priority trust mode as needed. Figure 396 shows the process of priority mapping on
a device.
Figure 396 Priority mapping process
Introduction to priority mapping tables
The device provides various types of priority mapping table, as listed below:
ï‚· CoS to DSCP: 802.1p-to-DSCP priority mapping table.
ï‚· CoS to Queue: 802.1p-to-local priority mapping table.
ï‚· DSCP to CoS: DSCP-to-802.1p priority mapping table, which is applicable to only IP packets.
ï‚· DSCP to DSCP: DSCP-to-DSCP priority mapping table, which is applicable to only IP packets.
ï‚· DSCP to Queue: DSCP-to-local priority mapping table, which is applicable to only IP packets.
Table 156 through Table 157 list the default priority mapping tables.
Table 156 The default CoS to DSCP/CoS to Queue mapping table
Input CoS value Local precedence (Queue) DSCP
0 2 0
1 0 8
2 1 16
3 3 24
4 4 32
5 5 40
6 6 48
7 7 56
Table 157 The default DSCP to CoS/DSCP to Queue mapping table
Input DSCP value Local precedence (Queue) CoS
0 to 7 0 0
8 to 15 1 1