Constraint-based Routing Label Distribution Protocol

From Wikipedia, the free encyclopedia

Constraint-based Routing Label Distribution Protocol (CR-LDP) is a control protocol used in some computer networks.

It is an extension of the Label Distribution Protocol, one of the protocols in the Multiprotocol Label Switching architecture. CR-LDP contains extensions for LDP to extend its capabilities such as setup paths beyond what is available for the routing protocol. For instance, a Label Switched Path can be setup based on explicit route constraints, quality of service constraints, and other constraints. Constraint-based routing (CR) is a mechanism used to meet traffic engineering requirements. These requirements are met by extending LDP for support of constraint-based routed label switched paths (CR-LSPs). Other uses for CR-LSPs include MPLS-based virtual private networks.