LDP%20extension%20for%20Inter-Area%20LSP%20draft-ietf-mpls-ldp-interarea-01

1
LDP extension for Inter-Area LSPdraft-ietf-mpls-l
dp-interarea-01

• Bruno Decraene France Telecom / Orange
  Jean-Louis Le Roux France Telecom / Orange
• Ina Minei Juniper Networks
• IETF 70 03/12/2007

2
Outline
1

• Summary of problem statement solution
• Overview of changes since latest presentation
• Next steps

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3
3
Problem Statement

• MPLS networks are expanding
• ? IGP areas are being introduced
• ? inter area LSPs needed
• LDP does not set up inter area LSPs if the IGP
  performs IP aggregation between areas
• RFC 3036/5036 mandates that the FEC should
  exactly match a RIB entry

Core
Backhaul 1
Backhaul 2
ABR router
PE1
PE2
P1
P2
P3
ABR2
ABR1
P4
PE router
P router
LSP
IS-IS L1
IP aggregation
IP aggregation
10.0.0.1/32
IS-IS L2
10.0.0/24
10.0.0.1/32
10.0/16
LDP
IS-IS
IP
LSP
10.0.0.1/32
10.0.0.1/32
LDP
MPLS
FEC - RIB Exact Match succeed
FEC - RIB Exact Match Failed
FEC - RIB Exact Match Failed
Aggregation between IGP areas
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Solution overview

• The draft proposes to accept the FEC if a longest
  match is found in the RIB

Core
Backhaul 1
Backhaul 2
ABR router
PE router
PE1
PE2
P1
P2
P3
ABR2
ABR1
P4
P router
LSP
IS-IS L1
IS-IS L2
IP aggregation
IP aggregation
10.0.0.1/32
LDP
10.0.0/24
10.0.0.1/32
10.0/16
LSP
IS-IS
IP
10.0.0.1/32
10.0.0.1/32
10.0.0.1/32
LDP
MPLS
Aggregation between IGP areas
LDP Exact Match
LDP Longest Match
LDP Longest Match

• Solution is also applicable to inter-AS LSP
• Inter-AS VPN option C.

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Draft history

• Latest presentation in IETF 67 (Pragues)
• draft-decraene-mpls-ldp-interarea-04
• Since then
• Draft became a WG document (06/2007)
• draft-ietf-mpls-ldp-interarea-00 submitted in
  07/2007
• Addressed all comments received on the list
• draft-ietf-mpls-ldp-interarea-01 submitted in
  11/2007
• Draft changes in v00 v01
• Editorial changes
• Clarifications on a few points
• Problem statement (4)
• Label mapping procedure (5)
• Deployment consideration (7.1)
• Impact on routing convergence (7.2)
• Technical specification is stable

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Conclusion

• Straightforward specification extension
• Solve an operational problem
• Existing deployments of multi-areas MPLS networks
  
• Very stable specification
• Over the last 2 years changes were mostly
  editorials and clarifications
• One implementation of the draft
• Authors believe the document is ready for last
  call.

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• Thank You