摘要 |
A technique protects against failure of a tail-end node of a Traffic Engineering (TE) Label Switched Path (LSP) in a computer network. According to the protection technique, a node along the TE-LSP that is immediately upstream to the protected tail-end node and that is configured to protect the tail-end node (i.e., the "point of local repair" or PLR) learns reachable address prefixes (i.e., "protected prefixes") of next-hop routers from the tail-end node (i.e., "next-next-hops," NNHOPs to the protected prefixes from the PLR). The PLR creates a backup tunnel to each NNHOP that excludes the tail-end node, and associates each backup tunnel with one or more protected prefixes accordingly. When the tail-end node fails, Fast Reroute is triggered, and the protected prefix traffic (from the TE-LSP) is rerouted by the PLR onto an appropriate backup tunnel to a corresponding NNHOP. Notably, the PLR performs a penultimate hop popping (PHP) operation prior to forwarding the traffic along the backup tunnel(s).
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