* * * # PALS/MPLS/DetNet Joint Meeting IETF 116 {#palsmplsdetnet-joint-meeting-ietf-116} * * * # Meeting Information {#meeting-information} Tuesday March 28, 2023 - 9:30-11:30 Meeting/Yokohama time Room: G302 120/120 min allocated Max participants observed: 71 Chairs: Dave SINICROPE, Nic LEYMANN Secretary: Dave SINICROPE Minute-taker: Dave SINICROPE (+attendees on CodiMD/HedgeDoc) Note: all persons with questions and comments (including those physically present) must line up into the virtual queue on Meetecho to be recognized \*\*\* # Agenda {#agenda} ## 1. Chairs Intro (Agenda Bashing, etc.) {#1-chairs-intro-agenda-bashing-etc} Duration: 5 min Chairs: Dave SINICROPE, Nic LEYMANN (for Stewart BRYANT and Andy MALIS) Dave went through the intro slides, noting the primary purpose of the session and in particular the discussion on the future of the open design team Note takers - add input into Hedgedoc and will be incorporated with Chair's notes for proceedings. Chair noted the session is being recorded. # Non-MNA Session {#non-mna-session} ## 2. https://datatracker.ietf.org/doc/html/draft-schmutzer-pals-ple {#2-httpsdatatrackerietforgdochtmldraft-schmutzer-pals-ple} Duration: 10 min Presenter: Christian SCHMUTZER Private Line Emulation (PLE) - Give an overview of improvements since revision -00 in preparation for an upcoming WG adoption call asking for WG adoption and feedback. Sasha: Transparent handling of all Layer 2 Control Protocol messages mentioned in the Synchronous Ethernet use case in the Intro of the draft may result in incorrect reporting of the recovered clock quality (which is carried in dedicated L2CP messages). IMHO this should be explicitly discussed in the (currently missing) Applicability Statement section of the draft. This comment should not be considered as blocking WG adoption of the document. Christian: we are trying to do something similar to an optical transport network and the optical network would have ehternet pass transparently. some of the assumptions for clock quality may not be present. Try to addressed in text on clock recovery and that requirements must be met by an implementation. Could add something more about the endpoints and loss packets, etc. We can discuss and would consider input. The boundaries have been stated. # MNA Session - {#mna-session--} ## 3. Open DT Report {#3-open-dt-report} Duration: 10 min Presenter: Tarek SAAD 5th report from the DT Tarek went through the slides Tarek highlighted the working group adoption polls for the MNA header - wide support (draft-jags) It was noted the post stack data did not have support and was removed from the document to be dealt with separately. The document on the extension headers was discussed. There was only minimal support and the decision was to not adopt the document. It was noted that the additional Editor (Greg Mirsky) has jumpstarted draft-ietf-mpls-1stnibble. It was noted that the DT meeting continuation needs to be discussed. See the Open Discussion below. Greg Mirsky: 2pts - without questioning conclusions - on the post stack data, there were technical concerns with the solution about the complexity of PSD. Question about last bullet on alternative solutions to PSD. In the framework and requirements document it notes optional support of PSD solutions, but are there documented use cases for MNA that can't be addressed with ISD? If there are cases that can't be addressed with ISD THEN (and only then) we should pursue PSD solutions. We should not pursue PSD solutions without a definitive reason. Tarek: there were technical points raised with PSD, but the majority of concerns were with IPR poll issues. For alternatives to PSD, one alternative is not to have an alternative. If we can show there is no need then we may not need to pursue it. Andrew Alston: clarification on IPR objections - the objections were not around IPR but rather the terms of the IPR. A WG can object to the terms of the IPR but not the validity of the IPR. Tarek - right we should make that clarification Weiqiang Cheng- there are use cases that could use PSD but then we see if ISD could work for them. Tarek: we've come to agreement that PSD is not high priority right now Jie Dong: We have looked into PSD and ISD. ISD is useful for some use cases and PSD is useful for others. Both options should be moved forward. See Tarek's prior comment ## 4. https://datatracker.ietf.org/doc/draft-ietf-mpls-mna-hdr {#4-httpsdatatrackerietforgdocdraft-ietf-mpls-mna-hdr} Duration: 10 minutes Presenter: Jaganbabu RAJAMANICKAM Jags presented the slides for WG draft above There was an overview of the MNA header and formats Loa: <*bad audio will take question to the list*> ## 5. https://datatracker.ietf.org/doc/draft-jags-mpls-ps-mna-hdr {#5-httpsdatatrackerietforgdocdraft-jags-mpls-ps-mna-hdr} Duration: 10 minutes Presenter: Jaganbabu RAJAMANICKAM update on new draft Jags presented the slides for draft above (same deck as presentation above) The slides went through the details of the several different PSD encodings. Welcoming comments and feedback Requestion WG adoption Joel Halpern: not concerned about formats - if we are going to do PSD then formats can be worked. The question however is *whether* PSD is *needed* at all. Any PSD solution adds complexity to the label stack. If ***needed*** OK, but so far there has been no clear demonstration of the need. What problem are we solving? Greg Mirsky: thanks for addressing questions raised on the list. Share concerns on complexity and need for PSD that can't be met with ISD. Is it really required based on analysis of use cases? If there is a documented use case that *can't* be solved with ISD MNA, then and only then should we look toward PSD MNA. It should also be noted that 0010 may conflict not with assigned labels but with SFC header first nibble. Will be examining this in more detal. Jags: we already have a use case document one use case is iOAM - Greg: It is not a conclusion of WG that IOAM can't be solved with ISD Rakesh: why do we need PSD? iOAM has multiple option types preallocated, direct export, edge to edge, etc. - some can be solved with ISD, others PSD would help e.g., recording of data on every hop there is time stamping this would be a good use for PSD. ## 6. https://datatracker.ietf.org/doc/draft-mb-mpls-ioam-dex {#6-httpsdatatrackerietforgdocdraft-mb-mpls-ioam-dex} Duration: 10 min Presenter: Greg MIRSKY IOAM Direct Export in MPLS Network Actions - Share updates to the draft resulting from aligning the proposal with the current ISD MNA solution based on draft-jags. Greg presented the slides This was presented to the Open DT and will give overview of solution Uses RFC 9197 header mapped into ISD MNA. Asking for feedback and WG adoption. ## 7. https://datatracker.ietf.org/doc/draft-gandhi-mpls-ioam {#7-httpsdatatrackerietforgdocdraft-gandhi-mpls-ioam} Duration: 10 minutes Presenter: Rakesh GANDHI New revision of the MPLS IOAM draft. The new revision is based on the new Post-Stack MNA draft (draft-jags-mpls-ps-mna-hdr). Rakesh presented the slides. draft was around pre MNA work and has been adapted to use MNA and draft-jags PSD proposed formats. Asking for WG adoption - the PS encoding is not a WG doc so doesn't make sense Questions on prior 2 drafts Jags: <*comment inaudible*> ## 8. https://datatracker.ietf.org/doc/html/draft-gandhi-spring-enhanced-srpm {#8-httpsdatatrackerietforgdochtmldraft-gandhi-spring-enhanced-srpm} Presenter: Rakesh GANDHI Duration: 5 minutes Enhanced SRPM draft, now using MNA encoding Rakesh presented SPRING draft asking for comments Greg Mirsky: 2nd slide - goal is to combine session reflector not being aware of measurement protocol to ensure accurate one way measurement - for one way the clocks must be synchronized so for one way measurement the reflector must put the timestamp. Also, with SR-MPLS how can you do accurate round trip measurements? If packet sent back on non-corouted path you end up measuring 2 paths. How can gurantee return path to be co-routed? Fang Gao: page 7 - delay T2-T1 if the reverse path is native IP. For RT what is the type of round trip? How to ensure it remains in the fast path? (question has been asked on the list) Rakesh: by default the response is native IP, but with SR could put reverse path. Fang Gao: If reverse path native IP - will it take some special destination? Will this satisfy clock synchronization, specifically time synchronization? - PTP timestamps must be in sync between the measurement points Rakesh: by default reply comes in IP/UDP. Segment-list can be used to ensure forward and reverse are co-routed. ## 10. https://datatracker.ietf.org/doc/html/draft-song-mpls-flag-based-opt {#10-httpsdatatrackerietforgdochtmldraft-song-mpls-flag-based-opt} Presenter: Rakesh GHANDI for Haoyu SONG Duration: 5 min Flag-based MPLS On Path Telemetry Network Actions Rakesh presented the slides Greg - There is an MPLS WG adopted draft for alternate marking ## 9. https://datatracker.ietf.org/doc/html/draft-liu-lsr-mpls-inspection-msd {#9-httpsdatatrackerietforgdochtmldraft-liu-lsr-mpls-inspection-msd} Presenter : Yao LIU Duration: 5 min Signaling Base MPLS Inspection MSD Yao presented the slides <*audio issues*> no questions or comments ## 11. https://datatracker.ietf.org/doc/draft-sx-detnet-mpls-queue {#11-httpsdatatrackerietforgdocdraft-sx-detnet-mpls-queue} Presenter: Xueyan SONG Duration: 10 min MPLS Sub-Stack Encapsulation for Deterministic Latency Action. Introduce a new MNA action used for DetNet Latency carried in MPLS packets and look for comments and co-operation to work on this solution. Xueyan presented the slides. It was noted that the draft has been progressed in Detnet. asking for feedback ## 12. Open Discussion {#12-open-discussion} Duration: 30 min a. Future of the Open MPLS DT Dave went through the Open DT continuation questions and pros and cons for both continuing and suspending Tony Li: Open DT calls have been useful - would like to continue with some kind of call and the administrivia should conform to need instead of vice versa. Joel: disagree with continuing the calls. Important that all interested parties can make calls. Given the list of things noted that need resolution, they all must be discussed with the WG, the authors have gone as far as they can. e.g., The WG must agree on wheither PSD is needed, not design of bits and formats. The Open DT doesn't conform with IETF procedures. Adrian: Agree with Tony AND Joel - agree that the DT has made great progress and could not have been done with whole WG... what is of concern is that the DT gives a feeling that it is making decisions vs recommendations. That it is documenting decisions vs documenting possibilities and getting design and steerage from the WG. Not easy for all who are interested to attend those meetings. The record of the DT progression is not coming through enough to the WG. The DT must design its role within the WG better, communicate better and be clear about fulfulling its role. Andrew: 2nd Adrian's comments - even as AD it is not possible to attend DT calls. Without constant feedback it creates a problem with keeping the role of the DT to keeping decision making to the WG. Loa: <*audio issues*> Tarek relaying Loa - Loa favors DT to bring recommendation to the WG so decision in the WG. This is process that we have been following and engaging the WG when a decision needs to be made. Here at this meeting we are presenting a decision on PSD. DT may still have a role to make recommendations. Zafar: agree with Joel - DT did a great job but we should resume WG process to get the job done to engage a wider wg community. Jie - agree with Adrian - easier to discuss with small group in DT instead of having discussion within whole WG. Could do a periodic report from DT to the WG email list. Joel: the fundamental disconnect is the difference between "Are DTs useful" and "What is the DT role?". If there is a specific problem that needs to be addressed to come to convergence and agreement is needed, then that would be a use for a design team. However WG decisions, and all things listed in the Chairs Intro as work to be done, should be resolved via email and via the WG process. It may be slower but it involves the entire community. Tony: DTs are a good things and we allow DTs to make decisions but DT decisions must be confirmed by the WG. Perhaps the real issue is to make this clearer. b. Open discussion - none # Information for the Session {#information-for-the-session} * This Agenda: https://datatracker.ietf.org/meeting/116/materials/agenda-116-pals * HedgeDoc Meeting Notes: https://notes.ietf.org/notes-ietf-116-pals * Chat room: https://zulip.ietf.org/#narrow/stream/pals * MPLS Open Design Team Wiki (The MPLS open design team keeps a log of its work here): https://wiki.ietf.org/en/group/mpls/odt/main * If you have any general issues with Meetecho, the meeting audio, etc., send an email to support@ietf.org (Note: a Meetecho tech will be monitoring the chat during the meeting)