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L2VPN Provisioning & Signaling. draft-ietf-l2vpn-signaling-03.txt. Eric Rosen Wei Luo Bruce Davie Cisco Systems. Vasile Radoaca Westridge Networks. The story so far. Prior versions of this draft describe modular approach to provisioning, discovery and signaling for L2VPNs
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L2VPN Provisioning & Signaling draft-ietf-l2vpn-signaling-03.txt Eric Rosen Wei Luo Bruce Davie Cisco Systems Vasile Radoaca Westridge Networks
The story so far • Prior versions of this draft describe modular approach to provisioning, discovery and signaling for L2VPNs • VPWS, VPLS (hierarchical, distributed, and vanilla) • LDP- & L2TPv3-based signaling • BGP-based autodiscovery • Other autodiscovery methods possible
Changes from -02 version • Main change: added new section on Inter-AS issues • Builds on "PW Switching" draft* • This forced some small changes to PW signaling procedures for VPLS (3.2.3 and 3.5.1) • Also added some clarifying text in BGP-based autodiscovery sections (3.2.2.1 and 3.3.2.1) * draft-martini-pwe3-pw-switching-01.txt
Multi-AS tunnel LSP model AC 3 AC 1 PE-3 PE-1 • PE-PE LSP is built as per RFC 2547, option (c) • Addresses of PEs + labels carried in BGP • PW signaling from PE-PE AS 1 AS 2 ASBR-2 ASBR-1 PE-2 PE-4 AC 4 AC 6 Tunnel LSP Attachment circuit Attachment circuit pseudo-wire LDP Auto-discovery (MP-iBGP) Auto-discovery (MP-iBGP) Auto-discovery (MP-eBGP)
Pseudo-wire "switching" model AC 3 AC 1 ASBR-2 ASBR-1 PE-3 pwid 34 PE-1 pwid 78 pwid 111 • Autodiscovery analogous to L3VPN Model (b) - eBGP used between ASBRs • Limiting PW signaling to ASBRs gives control over policy and avoids mesh of PE-PE signaling AS 1 AS 2 PE-2 PE-4 AC 4 AC 6 Pseudowire Attachment circuit Pseudowire Attachment circuit Pseudowire LDP / L2TPv3 LDP / L2TPv3 LDP / L2TPv3 Auto-discovery (MP-iBGP) Auto-discovery (MP-iBGP) Auto-discovery (MP-eBGP) draft-martini-pwe3-pw-switching-01.txt
BGP Autodiscovery • VPLS: BGP advertisement for a particular VSI at a given PE will contain: • an NLRI of AFI = L2VPN1, SAFI = TBD2, encoded as RD:PE_addr • a BGP next hop equal to the loopback address of the PE • extended community attribute containing one or more RTs • VPWS: BGP advertisement for a pool of attachment circuits at a given PE will contain: • an NLRI of AFI = L2VPN1, SAFI = TBD2, encoded as RD:pool_num • a BGP next hop equal to the loopback address of the PE • extended community attribute containing one or more RTs 1. Same for all L2VPN schemes (e.g. vpls-bgp)2. Same value for both cases in this draft
Changes to VPLS signaling • -02 assumed that signaling was PE-PE, therefore need only identify the VPLS instance within the PE • AGI = VPN-ID, TAII = SAII = null • When signaling between ASBRs, need to identify the PE as well • AGI = VPN-ID, TAII = PE_addr, SAII = null • Note: PE_addr is just an identifier, need not be routable • For Dist. VPLS, SAII = n - this allows multiple PWs from N-PE to N-PE
Next steps • draft-ietf-l2vpn-vpls-ldp-xx.txt should change to reflect this change (or just reference this draft) • Synchronize with draft-ietf-l3vpn-bgpvn-auto-xx.txt • WG last call for this draft?