Users Guide

DSCP/CP bit range
(in hexadecimal)
DSCP Definition Traditional IP
Precedence
Internal Queue ID DSCP/CP decimal
range
000xxx BE (Best Effort) Best Effort 0 0–7
• Enable the trust DSCP feature.
POLICY-MAP-IN mode
trust diffserv
Honoring dot1p Values on Ingress Packets
In an input QoS policy, you can configure the system to honor dot1p values on ingress packets using the
Trust dot1p feature.
The following table specifies the queue to which the classified traffic is sent based on the dot1p value.
Table 74. Default dot1p to Queue Mapping
Packet dot1p on Ingress Packet Queue ID
0 1
1 0
2 2
3 3
4 4
5 5
6 6
7 7
The dot1p value is also honored for frames on the default VLAN. For more information, refer to Priority-
Tagged Frames on the Default VLAN.
• Enable the trust dot1p feature.
POLICY-MAP-IN mode
trust dot1p
Mapping dot1p Values to Service Queues
All traffic is by default mapped to the same queue, Queue 0.
If you honor dot1p on ingress, you can create service classes based the queueing strategy in Honoring
dot1p Values on Ingress Packets. You may apply this queuing strategy globally by entering the following
command from CONFIGURATION mode.
• All dot1p traffic is mapped to Queue 0 unless you enable service-class dynamic dot1p on an
interface or globally.
• Layer 2 or Layer 3 service policies supersede dot1p service classes.
• Create service classes.
INTERFACE mode
service-class dynamic dot1p
854
Quality of Service (QoS)