H3C S5100-SI

1-9
Figure 1-5 Assign precedence to received packets in different trust modes
z Trusting port priority
In this mode, the switch replaces the 802.1p precedence value of the received packet with
the port priority, looks up the 802.1p-precedence-to-other-precedence mapping table for
the set of precedence values corresponding to the port priority of the receiving port and
assigns the matching precedence value set to the packet.
z Trusting packet priority
After configuring the switch to trust packet priority on a port, you can specify the trusted
priority type, which can be 802.1p precedence or DSCP precedence.
Table 1-5 describes
how your switch handles a packet received on the port.
Table 1-5 Actions performed when packet priority is trusted
Trusted priority type Description
802.1p precedence
1) The switch looks up the 802.1p-precedence-to-other-prec
edence mapping table for the set of precedence values c
orresponding to the 802.1p precedence of the packet.
2) When configuring the switch to trust the 802.1p
precedence of packets, you can further configure the
switch to process each received packet in one of the
following modes:
z In the default mode, deliver the packet with its original
DSCP value unchanged.
z In the automap mode, deliver the packet with the target
DSCP value after mapping in place of its original DSCP
value.