IETF 117 PCE WG Notes

Monday, 24 July 2023, Session III, 15:30 - 17:00 PT

• Chairs: Dhruv Dhody, Julien Meuric
• Secretary: Andrew Stone
• Note Taker: Andrew (add your name if you contribute in notetaking)
• Slides
• Video
• Chat-Stream
• Meetecho Recording

Introduction

1.1. Administrivia, Agenda Bashing (Chairs, 5 min) [5/90]

• Thanks Hari for your service

1.2. WG Status (Chairs, 10 min) [15/90]

1.3. State of WG I-Ds, open issues and next steps (Chairs, 10 min)
[25/90]

1.4. PCE WG Re-charter Discussion (Chairs, 10 min) [35/90]

• [Dhruv] - No comments from PCE WG members in room and general
  agreement on mailing list, will be sent to AD (John) for
  rechartering process.

Segment Routing

2.1 SR Policy (Mike Koldychev, 10 min) [45/90]

draft-ietf-pce-segment-routing-policy-cp-11

draft-ietf-pce-multipath-08

• [Mike] - If any other implementations please reach out to let me
  know.
• [Boris via chat] - Yes, there are working implementations from
  Juniper and Huawei.
• [Ketan] - Comment about segment list backup: some things are
  extended beyond SR Policy architecture. forward path is there,
  reverse is fine, but concern about backup. (SR policy) Semantics are
  for load balancing and not backup. Something to look at for SR
  Policy perspective. If it's not there better to take it off.
• [Mike] - Agree let's see and we can move or remove
• [Cheng] - Agree with Ketan about the backup, it's not in the SR
  Policy architecture. We have something similar in another WG
  document, bidirectional path. So regarding reverse path should be
  moved out as well.
• [Mike] - Reverse isn't part of SR policy, but at same time it is
  useful. If desire to move it can be moved
• [Cheng] Can go offline and discuss more.
• [Dhruv] - Agree, limit it to what's in SR policy architecture.
  Regarding stateful bring up, since it is doing RFC update, use the
  appropriate meta data and indicate what is being updated. Any
  thoughts on reusing existing capability tlv for the new flags?
• [Mike] - Cleaner to have all in one but we can probably re-use.
• [Dhruv] - Can see value of seperate or re-use existing.
• [Dhruv] - What's the status of operational draft? Thought two
  documents?
• [Mike] - Going to remove parts that modify rfc8321.
• [Dhruv] - Other than stateful bring up nothing else updates
  rfc8321?
• [Mike] - Correct.
• [Andrew] - Backup path comes from replication segment, and was
  added to multipath. Agree with others shouldn't be in unicast sr
  policy. Still needed for replication segment solution so should be
  moved from here.

2.2 SRv6 (Cheng Li, 10 min) [55/90]

draft-ietf-pce-segment-routing-ipv6-17

• [Ketan] - Discussed in person earlier, Dhruv suggested proposal.
  Doesn't make sense to remove MSD due to implementation out there,
  but clarification on how SRv6 is relevant to the transit nodes is
  needed. PCECC use case also impacted. On the X-bit, agree, we should
  poll if any implementation and remove if not.
• [Cheng] - Agree.
• [Dhruv] - If we resolve MSD, then only x flag topic remains. WG
  any comments? otherwise mailing list. One possible option is to add
  warning.
• [Ketan] - MSD is platform capability, not really config.
• [Dhruv] - In IGP/BGP-LS, MSD is considered optional, isn't
  similar?
• [Ketan] - If its not there (in BGP-LS advertisement), then
  considered not supported. Condition is left undefined.
• [Dhruv] - WG please use list to give feedback (regarding X flag).
• [Boris] - Implementation status should be updated too, I'm aware
  of some others implementations.
• [Dhruv] - Send them to the list please.

2.3 SID Algo (Samuel Sidor, 10 min) [65/90]

draft-ietf-pce-sid-algo-03

• [Dhruv] - Update looks good. Number of authors should be limited
  to 5, better to do it earlier than later.
• [Samuel] - Agree, planned to do it but postponed, still some
  adjustments.
• [Dhruv] - Any pending issues?
• [Samuel] - Better error handling for non-supported parts of the
  draft of failure for PCE to compute a path, maybe some codes to be
  exchanged.

2.4 SR Segment-List Optimization and Validation (Ran Chen, 10 min)
[75/90]

draft-lin-pce-srv6-segment-list-optimize-00

• [Dhruv] - Did you present in SPRING WG? any feedback?
• [Ran] - Yes, no feedback yet.
• [Dhruv] - Please also continue to check with SPRING. From PCEP,
  can NAI solve what you're trying to do? NAI can carry loopback
  address.
• [Ran] - Okay, thank you.

draft-chen-pce-sr-policy-cp-validity-00

• [Andrew] - A similar solution document seems related in SPRING,
  might be worth double checking if overlap.
• [Ran]- The focus of these two drafts are different. That draft
  mainly focuses on how to choose the CPs, but our draft is to define
  the cp validity control parameters to control the validity judgement
  of candidate path。
• [Dhruv] - The TLV format is not as per PCEP TLV format. Looks like
  you copied it from BGP.

Stateful PCE

3.1 Auto-Bandwidth Update (Dhruv Dhody, 10 min) [85/90]

draft-peng-pce-stateful-pce-autobw-update-00

• [Boris] - Sounds reasonable.
• [John] - Case is persuasive, seems reasonable to move forward.

Others

4.1 PCEPS update for TLS 1.3 (Sean Turner, 5 min) [90/90]

draft-ietf-pce-pceps-tls13-00

• [Dhruv] - We do want to move forward, but want to give WG a chance
  to raise any concerns.
• [Sean] - Another draft in netconf mirrors itself there too.
• [Dhruv] - Current status?
• [Sean] - Done WGLC, going on its way to IESG.
• [Adrian-Chat] - Prioritize it and get it done.