System and method for finding segments of path for label switched path crossing multiple domains

摘要

An apparatus comprising a path computation element (PCE) associated with a domain in a network and configured to find a segment of a Multiprotocol Label Switching (MPLS) Traffic Engineering (TE) Label Switched Path (LSP) that crosses a plurality of domains in the network using a Constraint Shortest Path First (CSPF) algorithm or a reverse CSPF algorithm that computes a plurality of shortest paths in the domain of which the segment is selected, wherein the CSPF algorithm or the reverse CSPF algorithm is selected to reduce the number of shortest path computations in the domain based on the number of starting nodes and ending nodes that are considered for computing the shortest paths in the domain.