Patent ID: 7558276

Claim:
A method for retrieving computed path segments across one or more domains of a computer network in accordance with a stateful path computation element (PCE) model, the method comprising: receiving a path computation request issued by a Path Computation Client (PCC) at a first network interface; computing one or more path segments in response to the path computation request; associating each path segment with a path key; storing the one or more path segments with each associated path key; returning, by the first network interface, or by a second network interface to the PCC, a path computation response, including the path key and a computed path containing compressed path descriptions of the computed path segment; receiving a path computation request from a border router, including the path key at the first network interface or at the second network interface or at a third network interface; extracting the path key; indexing into the stored path keys to match a particular path segment to the extracted path key; and returning the computed path segment stored in a matching entry to the border router via a path computation reply sent by the first or by the second or by the third or a fourth network interface.