Segment Protection Scaling

1
Segment Protection Scaling

• Bob Sultan (bsultan_at_huawei.com)
• Deng Zhusheng

2
TESI Segment Protection Requirement
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• PBB-TE supports end-to-end TESI protection
• Requirement to protect a TESI segment
• See Vinod Kumar Service Provider Requirements

3
TESI Segment Protection
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C

• Segment endpoints are MEPs
• CCM detects connectivity state of W/P
• Switch achieved by FDB update at endpoints
• Simple scheme based on existing 802.1ag
• End-to-end TESI protection/CCM as usual

4
Segment Protection Scaling Issue
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• Many TESIs can use same set of links for W/P
• Requires W/P CCMs per TESI segment
• Can be scaling problem in some cases

5
Scaling Segment Protection with Cycle
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cycle
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C

• Observe that WP segments always form a cycle
• Observe that many paths may use the same cycle
• Replace CCM per segment (many) with one fault
  notification per cycle
• Please note this use of the word cycle has
  absolutely nothing to do with p-cycles. A
  cycle is just a closed loop of links.

6
Summary

• We support CCM-based segment protection
• We propose cycle-based notification for scaling
  purposes for cases in which many segments use the
  same cycle (cycle is provisioned)
• Notification mechanism could re-use G.8032 or
  ring/cycle mechanism developed in 802.1 (see Norm
  Finn proposal).