Patent ID: 7586841
Filing Date: 2009-09-08
Classification: H04L

Abstract:
1. A method for protecting against failure of a tail-end node of a Traffic Engineering (TE) Label Switched Path (LSP) in a computer network, the method comprising: learning, at a point of local repair (PLR) along the TE-LSP, reachable address prefixes of next-hop routers from the tail-end node (NNHOPs); creating a backup tunnel from the PLR to each NNHOP that excludes the tail-end node; associating each backup tunnel with one or more learned address prefixes; and in response to failure of the tail-end node, i) performing a penultimate hop popping (PHP) operation on traffic received along the TE-LSP at the PLR, and ii) rerouting the received traffic at the PLR onto an appropriate backup tunnel to an NNHOP corresponding to a destination prefix of the traffic.