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Y.1711 & LSP-PING draft-allan-y1711-and-lsp-ping-00.txt PWE3_WG@IETF 56 Dave Allan Nortel Networks draft-allan-y1711-and-lsp-ping-00.txt Motivations • Highlight the complementary nature of Y.1711 and LSP-PING • Draft is purely informational draft-allan-y1711-and-lsp-ping-00.txt Y.1711 • General attributes – Minimalist MPLS specific protocol designed for proactive fault detection (no diagnostic capability) – Egress defect detection paradigm • Minimal dependencies on “non-LSP” components • Maximize determinism – “I can detect that fault in three transactions” – Primarily an edge function • Gains functionality if core implements fault notification – Outcomes are “pass/fail”, “what to do” and “where to start looking” draft-allan-y1711-and-lsp-ping-00.txt Y.1711 Status • Nov 2002 Recommendation – Focus on P2P LSPs, no PHP – CV (heartbeat), FDI (forward), BDI (backward) defect notifications – Specifies defect states and consequent actions draft-allan-y1711-and-lsp-ping-00.txt Y.1711 PWE3 Implications • Egress detection paradigm combined with defect notification simplifies interworking (both overlay/network and peer/service) – AIS/RDI/LMI etc. • As this is for MPLS, hierarchy is supported – Can reduce “chattyness” required to detect PW/PSN faults • Defect notification facilitates alarm suppression – For both PSN and PW clients • Data plane defect notification mechanisms reduce control plane load – Don’t need to withdraw PW labels to say something is wrong. draft-allan-y1711-and-lsp-ping-00.txt Y.1711 New Work • FEC-CV for LDP/MP2P/BGP etc. – Adds “bloom filter” to CV to encode FEC info. as a bit string (128 bit) • Functions as an application independent “fingerprint” • Extensible via defining coding rules for new applications – Actual message handling is unchanged – Initial focus was misbranching detection • Any into any (LDP/BGP/RSVP/PWs etc.) – Current proposals relate to LDP availability • Plug & play as PW FEC can be bound to PE ingress point dynamically draft-allan-y1711-and-lsp-ping-00.txt LSP-PING • UDP/IP protocol • Ping/traceroute paradigm – Augmented with FEC information • Good for CLI/craftsperson invocation – Achieves this by having lots of non-LSP dependencies • Results of any one transaction are indeterminate • Good diagnostic capability – Traceroute and downstream mapping functions permit currently deployed networks to be “characterized” • But difficult to scale for proactive detection draft-allan-y1711-and-lsp-ping-00.txt Conclusion • Y.1711 and LSP-PING are complementary in philosophy and design… – Y.1711 is a first line detection tool – LSP-PING has most utility as a diagnostic tool • Both have a place in an overall operational framework. draft-allan-y1711-and-lsp-ping-00.txt For Further Reference • ITU-T Recommedation Y.1711 (2002) “OAM Mechanism for MPLS Networks” • draft-ietf-mpls-lsp-ping-02.txt • For FEC-CV specifically http://standards.nortelnetworks.com/y.1711_fec_cv_public.pdf OR http://standards.nortelnetworks.com/y.1711_fec_cv_public.ppt draft-allan-y1711-and-lsp-ping-00.txt