Implementing Mpls Static Labeling - Cisco CRS Configuration Manual

Implementing MPLS Static Labeling

The MPLS static feature enables you to statically assign local labels to an IPv4 prefix per VRF. Also, Label
Switched Paths (LSPs) can be provisioned for these static labels by specifying the next-hop information that
is required to forward the packets containing static label.
If there is any discrepancy between labels assigned statically and dynamically, the router issues a warning
message in the console log. By means of this warning message, the discrepancy can be identified and resolved.
Static labels are more advantageous than dynamic labels because static labels:
• Improve security because the risk of receiving unwanted labels from peers (running a compromised
MPLS dynamic labeling protocol) is reduced.
• Gives users full control over defined LSPs.
• Utilize system resources optimally because dynamic labeling is not processed.
To perform static binding of MPLS labels, you need to:
• Enable MPLS Encapsulation on an Interface, on page 102
• Define a Range for Static MPLS Labels, on page 103
• Allocate static label:
◦ Setup a Static LSP, on page 104
or
Allocate Static MPLS Label to an IP Prefix and Configure a LSP, on page 105
◦ Allocate Static MPLS Label for a Specific VRF, on page 107
• Verify MPLS Static Bindings, on page 108
• Identify and Clear Label Discrepancy, on page 109
Restrictions
• Static labeling on IPv6 packets is not supported.
• The router does not prevent label discrepancy at the time of configuring static labels. Any generated
discrepancy needs to be subsequently cleared.
C H A P T E R
Cisco IOS XR MPLS Configuration Guide for the Cisco CRS Router, Release 5.1.x
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