Qinq Mpls Experimental Marking; Set Mpls Experimental Imposition Command; Syntax Description; Set Mpls Experimental Imposition Command History - Cisco 10000 Series Configuration Manual

Chapter 7 Marking Traffic
The value of the EXP bits determines the per-hop behavior (PHB) for MPLS nodes and is also used as
transparency mechanisms when used with MPLS DiffServ tunneling modes such as pipe and uniform
modes. IP marking does not modify an MPLS packet carrying IP data. You must configure MPLS
marking on an input interface. MPLS marking takes effect only during label imposition. You can
combine marking and policing to change the DSCP and MPLS EXP values of an IP packet during MPLS
label imposition.
A provider edge (PE) router at the edge of the MPLS network can be configured to map the DSCP or IP
precedence field to the MPLS EXP field. The router uses the value of the EXP field as the basis for IP
QoS. As a result, MPLS routers can perform QoS features indirectly, based on the original IP precedence
field inside the MPLS-encapsulated IP packet. The IP packet does not need to be opened to examine the
IP precedence field. When a packet leaves the MPLS network, IP QoS is still based on the DSCP or IP
precedence value in the IP header.

QinQ MPLS Experimental Marking

For CoS-to-EXP mapping in QinQ configurations, the parallel express forwarding (PXF) engine looks
at the CoS bits in the outer dot1q header to determine how to mark the EXP bits.
For EXP-to-CoS mapping in QinQ configurations, the PXF marks both the inner and outer CoS bits.

set mpls experimental imposition Command

To set the value of the Multiprotocol Label Switching (MPLS) experimental (EXP) field on all imposed
label entries, use the set mpls experimental imposition command in policy-map class configuration
mode. To disable the setting, use the no form of the command. By default, no MPLS EXP value is set.
set mpls experimental imposition mpls-exp-value
no set mpls experimental imposition mpls-exp-value

Syntax Description

mpls-exp-value

set mpls experimental imposition Command History

Cisco IOS Release
Release 12.0(22)S
Release 12.3(7)XI1
Release 12.2(28)SB
OL-7433-09
Specifies the value used to set the MPLS EXP bits. Valid values are from 0
to 7.
Description
The set mpls experimental command was introduced on the PRE1.
The set mpls experimental imposition command was introduced on the
PRE2.
This command was integrated in Cisco IOS Release 12.2(28)SB for the
PRE2.
Cisco 10000 Series Router Quality of Service Configuration Guide
MPLS Experimental Marking
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