Patent attributes
Parallelism is exploited to accelerate the distributed computation of an MPLS Traffic Engineering LSP across multiple Autonomous Systems or areas using a virtual shortest path tree. After relaying a path computation request, a path computation element immediately begins local path segment computations even before a response to the request is received. When a response including virtual shortest path tree information is received, the tree is extended using the previously computed path segments. Also, a path computation element can verify the local feasibility of the requested path after receiving a request so that a requesting head-end or upstream path computation element can be quickly informed that a constraints-satisfying path is not available.
