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VPLS/IPLS Full Mesh Failures. Assumption that full mesh of PWs is present. If assumption fails, black holes can occur. Failure modes: Data plane failures that misdirect or drop packets Loss of proper PW state at edges Auto-discovery/configuration failures
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VPLS/IPLS Full Mesh Failures • Assumption that full mesh of PWs is present. • If assumption fails, black holes can occur. • Failure modes: • Data plane failures that misdirect or drop packets • Loss of proper PW state at edges • Auto-discovery/configuration failures • But remember: PWs not real wires • Implemented via any-any network • Increase in error coverage is small: • Failures not caused by backhoes, router outages, but by bugs and errors. L2VPN WG
Bad Ideas for Detecting Failure • Local Information (detection only): • mismatch between operational PWs and discovered endpoints • PW operational status changes • Global Information (with resilience): • PWs as overlay network, run SPT • PWs as overlay network, run routing L2VPN WG
Not Quite So Bad Idea? • Global Information (detection only) • Each edge tells every other edge “here are the PW endpoints I can talk to” • Get global info, from each edge, set of other edges that can be seen. • Any edge not universally seen is removed from mesh. • Is this worth pursuing? L2VPN WG