Technical Documentation

Option: Stripping MPLS Labels on ATM, Ethernet-Based, and SONET/SDH Interfaces

Because flow monitoring can be performed only on IPv4 packets, any packets containing MPLS labels must have the labels removed before monitoring can occur. To remove MPLS labels from packets as they enter an ATM2 IQ, Ethernet-based, or SONET/SDH interface, include the pop-all-labels statement at the [edit interfaces interface-name-fpc/pic/port (atm | fastether | gigether | sonet)-options mpls] hierarchy level. If you use static MPLS labels, we recommend you assign label values from 10000 through 99999 to avoid using the label ranges reserved by the JUNOS Software.

To remove a specified number of labels from selected packets with MPLS labels, include the required-depth statement at the [edit interfaces interface-name-fpc/pic/port (atm | fastether | gigether | sonet)-options mpls pop-all-labels] hierarchy level. A required-depth value of 1 removes labels from all packets containing only one MPLS label, a value of 2 removes labels from all packets containing only two MPLS labels, and a value of [1 2] removes labels from all packets containing either one or two MPLS labels. The required-depth value of [1 2] is the default setting. When you configure the required-depth statement, you must configure the same value for all ports on the same PIC.

The labels are removed and discarded as soon as they arrive at the interface. As a result, no MPLS filters can be applied to the stripped labels, no statistics are generated for the labels, and you cannot apply an IP filter to the incoming packets. No Tunnel Services PIC is required to perform MPLS label stripping.

[edit]interfaces {at-/fpc/pic/port {atm-options {mpls {pop-all-labels {required-depth 1;}}}}(fe | ge)-fpc/pic/port {(fastether | gigether)-options {mpls {pop-all-labels {required-depth [1 2];}}}}so-fpc/pic/port {sonet-options {mpls {pop-all-labels {required-depth 2;}}}}}

Published: 2010-04-15