Implementing Mpls Label Distribution Protocol - Cisco ASR 9000 Series Configuration Manual

Implementing MPLS Label Distribution Protocol

The Multiprotocol Label Switching (MPLS) is a standards-based solution driven by the Internet Engineering
Task Force (IETF) that was devised to convert the Internet and IP backbones from best-effort networks into
business-class transport mediums.
MPLS, with its label switching capabilities, eliminates the need for an IP route look-up and creates a virtual
circuit (VC) switching function, allowing enterprises the same performance on their IP-based network services
as with those delivered over traditional networks such as Frame Relay or ATM.
Label Distribution Protocol (LDP) performs label distribution in MPLS environments. LDP provides the
following capabilities:
• LDP performs hop-by-hop or dynamic path setup; it does not provide end-to-end switching services.
• LDP assigns labels to routes using the underlying Interior Gateway Protocols (IGP) routing protocols.
• LDP provides constraint-based routing using LDP extensions for traffic engineering.
Finally, LDP is deployed in the core of the network and is one of the key protocols used in MPLS-based
Layer 2 and Layer 3 virtual private networks (VPNs).
Feature History for Implementing MPLS LDP
Release
Release 3.7.2
Release 4.0.1
Release 4.2.1
• Prerequisites for Implementing Cisco MPLS LDP, page 6
• Information About Implementing Cisco MPLS LDP, page 6
• How to Implement MPLS LDP, page 20
OL-28381-02
Modification
This feature was introduced.
Support was added for these features:
• IP LDP Fast Reroute Loop Free Alternate
• Downstream on Demand
Support was added for LDP Implicit Null for IGP Routes.
Cisco ASR 9000 Series Aggregation Services Router MPLS Configuration Guide, Release 4.3.x
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