2. CR-LDP Constraint-based Routing LDP

CR-LDP meets the needs of network operators for traffic engineering tools. It is essential to be able to reproduce, at least in part, in an MPLS network what operators used to use in ATM networks (cf. ) and Frame Relay (see [H 2 285] ). For this reason, LDP has been extended to include functions for constraining the routing of LSPs and associating QoS characteristics with them.

The most important change was to create a much stronger notion of LSP than that which existed diffusely in LDP. In CR-LDP, an LSP is a path voluntarily established from a point,...