Constraint-based path computation is a strategic component of traffic engineering in MPLS, GMPLS and Segment Routing networks.
Path computation has previously been performed either in a management system or at the head end of each LSP.
PCE applications compute label-switched paths for MPLS and GMPLS traffic engineering.
[2] PCE represents a vision of networks that separates route computations from the signaling of end-to-end connections and from actual packet forwarding.
[4] Since the early days, the PCE architecture has evolved considerably to encompass more sophisticated concepts and allow application to more complicated network scenarios.