FAST REROUTE USING LOOP FREE ALTERNATE NEXT HOPS FOR MULTIPOINT LABEL SWITCHED PATHS

摘要

The techniques of this disclosure provide local protection for network traffic in multipoint label switched paths (LSPs) due to link or node failure using loop-free alternate (LFA) next hops. The techniques include establishing a vanilla or point-to-point (P2P) LSP with LFA next hops between routers of a multipoint LSP for use in the event of link or node failure in the multipoint LSP. Upon a failure, the multicast traffic is tunneled between the routers using the P2P LSP with LFA to an alternate next hop with an associated label stack. The techniques of this disclosure define the label stack as including a P2P LSP label as well as a multipoint LSP label. In this way, the P2P LSP with LFA may be used for fast reroute (FRR) of traffic in the multipoint LSP until a convergence process completes for a new multipoint branch of the multipoint LSP.