BGP%20Point-to-Multipoint%20LSP%20draft-satoru-mpls-bgp-multipoint-02

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BGP Point-to-Multipoint LSPdraft-satoru-mpls-bgp
-multipoint-02

• Satoru Matsushima (satoru_at_ft.solteria.net)
• Tetsuya Murakami (tmurakam_at_cisco.com)
• Kenichi Nagami (nagami_at_inetcore.com)

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Motivation

• Expand P2MP-LSP enabled area
• Cover non-TE area
• Cover non-MPLS area and inter-work w/ MPLS
  p2mp-lsp
• Inter-AS/Domain p2mp-lsp
• BGP is applicable for these motivations

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Requirements

• Discover/Notify P2MP capable branch and egress
  nodes
• Applicable for any P2MP signaling protocol
• Inter-Domain P2MP LSP
• P2MP LSP can be used over P2P/MP2P LSP
• Migration and co-existing scenarios
• Policy based P2MP tree decision
• Per LSP basis

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Overview of BGP for P2MP LSP
IngressLSR-a
BranchLSR-b
BranchLSR-c
EgressLSR-d
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BGP P2MP-LSP example
Sender
IngressLSR1
BranchLSR2
BranchLSR4
Egress LSR7
LSR3
Receiver3
Egress LSR5
Egress LSR6
P2P-LSP
Receiver1
Receiver2
P2MP Instance
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Proposal

• New BGP attribute
• P2MP_ID (ext community)
• Identify the P2MP_LSP
• P2MP_BRANCH_LIST (ext community)
• Indicate the branches which traverse P2MP_LSP
• Detecting and protecting loop
• P2MP_IMPORTED_BRANCH (ext community)
• Indicate the upstream branch of downstream LSR
  (JOIN)
• NLRI
• Distinguish ingress and each branches uniquely
  even if in same LSP
• Label distribution from downstream LSR

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Data plane of BGP P2MP

• P2MP instance
• The entity of replication and stitching P2P/MP2P
  LSP
• BGP makes policy of which is upstream/downstream
  for each P2MP LSP
• Other P2MP signaling can be used
• Data plane is separated as P2MP instance
• RSVP and LDP may use BGP as find p2mp capable
  node
• Inter-work w/ BGP P2MP-LSP

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Current status

• Deployment
• Current MPLS network co-existing w/ this solution
  is working
• Validating attribute and behavior
• Problem
• Defining a NLRI for P2MP AFI/SAFI is needed
• Currently, vpnv4 is used to distinguish p2mp LSP
• To keep bgp modularity and protecting miss
  behavior w/ MPLS-VPN

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Next step

• Good start point to develop BGP based P2MP
  discussion
• Interest for this work?
• Adopt as WG item?
• Please send your comment to the list