Re: [Lsr] Moving Forward [Re: Flooding Reduction Draft Redux]

[John E Drake <[e-mail]>]

Hi,

I completely agree with Peter.

Yours Irrespectively,

John

> -----Original Message-----
> From: Lsr <[e-mail]> On Behalf Of Peter Psenak
> Sent: Thursday, February 14, 2019 2:30 AM
> To: Huaimo Chen <[e-mail]>; Acee Lindem (acee)
> <[e-mail]>; Christian Hopps <[e-mail]>; [e-mail]
> Subject: Re: [Lsr] Moving Forward [Re: Flooding Reduction Draft Redux]
> 
> Hi Huaimo,
> 
> On 13/02/2019 22:50 , Huaimo Chen wrote:
> > Hi Peter,
> >
> >     My explanations/answers are in line below with prefix [HC].
> >
> > -----Original Message-----
> > From: Peter Psenak [mailto:[e-mail]]
> > Sent: Wednesday, February 6, 2019 4:58 AM
> > To: Huaimo Chen <[e-mail]>; Acee Lindem (acee)
> > <[e-mail]>; Christian Hopps <[e-mail]>; [e-mail]
> > Subject: Re: [Lsr] Moving Forward [Re: Flooding Reduction Draft Redux]
> >
> > Hi Huaimo,
> >
> > On 03/02/2019 17:58 , Huaimo Chen wrote:
> >> Hi Acee,
> >>
> >>
> >>
> >>     I agree with you on keeping the signaling for two modes. The
> >> other parts for the distributed solution need to be removed.
> 
> optimized flooding is not only about algorithm to calculate the flooding
> topology and the way it is distributed/computed. It is also about local rules to
> make sure the flooding remains consistent. These are _independent_ of
> centralized/distributed modes. And it make no sense to specify these rules in
> two drafts.
> >
> > There are no "other" parts specific for the distributed solution.
> >
> > [HC] Some behaviors for the distributed solution/mode are described in draft-
> li-dynamic-flooding. For example, there are a few of places from page 27 to 30,
> which define the behaviors specific for the distributed solution/mode.
> 
> I strongly disagree. The fact that we say in centralized mode area leader
> recomputes and in distributed mode all nodes recompute make no difference in
> behavior.
> 
> thanks,
> Peter
> 
> >
> > draft-li-dyanmic-flooding defines:
> >
> > 1. the signalling that is common and used by both modes 2. distribution of the
> flooding-topology, which is specific to centralized mode 3. common behavior of
> the nodes that support the extension, which is independent of the mode of
> operation.
> >
> > [HC] In addition to these, draft-cc-lsr-flooding-reduction defines more,
> including concrete protections, operations, and algorithms for computing a
> flooding topology.
> >
> > Best Regards,
> > Huaimo
> >
> > thanks,
> > Peter
> >
> >
> >>
> >>
> >>
> >> Best Regards,
> >>
> >> Huaimo
> >>
> >> *From:* Acee Lindem (acee) [mailto:[e-mail]]
> >> *Sent:* Sunday, February 3, 2019 11:45 AM
> >> *To:* Huaimo Chen <[e-mail]>; Christian Hopps
> >> <[e-mail]>; [e-mail]
> >> *Subject:* Re: [Lsr] Moving Forward [Re: Flooding Reduction Draft
> >> Redux]
> >>
> >>
> >>
> >> Hi Huaimo,
> >>
> >>
> >>
> >> See inline.
> >>
> >>
> >>
> >> *From: *Lsr <[e-mail] <mailto:[e-mail]>> on
> >> behalf of Huaimo Chen <[e-mail]
> >> <mailto:[e-mail]>>
> >> *Date: *Saturday, February 2, 2019 at 12:27 AM
> >> *To: *Christian Hopps <[e-mail] <mailto:[e-mail]>>,
> >> "[e-mail] <mailto:[e-mail]>" <[e-mail]
> >> <mailto:[e-mail]>>
> >> *Subject: *Re: [Lsr] Moving Forward [Re: Flooding Reduction Draft
> >> Redux]
> >>
> >>
> >>
> >> Hi Everyone,
> >>
> >>
> >>
> >> We proposed the distributed solution first, and Tony proposed the
> >> centralized solution first. Tony added the distributed solution
> >> (except for the algorithms to compute flooding topology) into his
> >> draft. And then we added the centralized solution into our draft. The
> >> latest versions of the two drafts have largely converged at least at
> >> the high level to a solution for solving the same problem.
> >>
> >>
> >>
> >> Our draft has multiple key technical advantages over Tony's draft as
> >> we described in our email to the LSR list, which are summarized below:
> >>
> >> 1.       It uses a fraction of flooding resource (i.e., it is multiple
> >> times more efficient in flooding topology encoding);
> >>
> >> 2.       It provides fault tolerance to multiple failures, minimizing
> >> impact on network convergence, thus minimizing traffic lose; and
> >>
> >> 3.       It is simpler and needs less processing time (i.e., faster and
> >> more efficient) in multiple scenarios.
> >>
> >> Based on the technical merits, our draft should be moved forward.
> >> However, Chair proposed to move Tony's draft forward and have us work
> >> on a distributed algorithm as we started with.
> >>
> >>
> >>
> >> I think that the distributed solution in Tony's draft needs to be
> >> removed and they work on the centralized solution. We remove the
> >> centralized solution from our draft and work on the distributed solution.
> >>
> >>
> >>
> >> I'm against "cutting the baby in half" given that the signaling for
> >> the distributed solution is a proper subset of what is required for
> >> the centralized solution. It is undesirable to have different
> >> signaling for the two modes. For the distributed algorithm you are
> >> proposing, do see problems with the signaling?
> >>
> >>
> >>
> >> Thanks,
> >>
> >> Acee
> >>
> >>
> >>
> >> Best Regards,
> >>
> >> Huaimo
> >>
> >>
> >>
> >> -----Original Message-----
> >>
> >> From: Lsr [mailto:[e-mail]] On Behalf Of Christian Hopps
> >>
> >> Sent: Friday, February 1, 2019 7:26 AM
> >>
> >> To: [e-mail] <mailto:[e-mail]>
> >>
> >> Cc: [e-mail] <mailto:[e-mail]>
> >>
> >> Subject: [Lsr] Moving Forward [Re: Flooding Reduction Draft Redux]
> >>
> >>
> >>
> >>
> >>
> >> Summary of where we are at with dynamic flooding reduction:
> >>
> >>
> >>
> >> - We have a well written original work that came first and described
> >> the problems as well as a TLVs to allow for a centralized solution
> >> (draft-li-dyanmic-flooding). We do not need to standardize the
> >> centralized algorithm.
> >>
> >>
> >>
> >> - A small change to this work allowed for distributed algorithms and
> >> for outside work on distributed algorithms to continue in parallel.
> >>
> >>
> >>
> >> - We have another original work that started primarily as a
> >> distributed algorithm
> >>
> >>    (draft-cc-ospf-flooding-reduction)
> >>
> >>
> >>
> >> - Finally we also have:
> >>
> >>    - Cross-pollination of ideas.
> >>
> >>    - Failed attempts at merging.
> >>
> >>    - An authors list "Arms-Race".
> >>
> >>
> >>
> >> Moving forward:
> >>
> >>
> >>
> >> - During IETF 103 I proposed we have no conflict if we:
> >>
> >>
> >>
> >>    1) adopt draft-li-lsr-dyanmic-flooding as the base WG document.
> >>
> >>    2) have authors of draft-cc-lsr-flooding-reduction work on a
> >> distributed algorithm as they started with.
> >>
> >>
> >>
> >> - Acee agreed during the meeting (as chair) that this was the best
> >> way forward. We had some agreement form the floor as well..
> >>
> >>
> >>
> >> - Any good ideas regarding the distribution of a centralized topology
> >> can be debated and added (with appropriate attribution) to the base
> >> document after we adopt one.
> >>
> >>
> >>
> >> - This is what happens when we adopt a document as WG work, we work on
> it.
> >>
> >>
> >>
> >> - The original authors of the distributed solution can continue to
> >> work on their distributed algorithm in a separate document which
> >> would also need standardization.
> >>
> >>
> >>
> >> Does anyone see a serious problem with this path forward?
> >>
> >>
> >>
> >> Thanks,
> >>
> >> Chris & Acee.
> >>
> >> LSR Chairs.
> >>
> >>
> >>
> >> Christian Hopps <[e-mail] <mailto:[e-mail]>> writes:
> >>
> >>
> >>
> >>> We've had the authors of the individual conflicting drafts take a
> >>> shot
> >> at merging their work.
> >>
> >>>
> >>
> >>>    This has failed.
> >>
> >>>
> >>
> >>> Here is the full history (which I also summarized during IETF103 as
> >> well). I will send a second email discussing this.
> >>
> >>>
> >>
> >>> - Jan 2, 2018 Publication: draft-li-dynamic-flooding and
> >> drfat-li-dynamic-flooding-isis
> >>
> >>>   published centralized solution.
> >>
> >>>
> >>
> >>> - Mar 5, 2018 Publication: draft-cc-isis-flooding-reduction and
> >> draft-cc-ospf-flooding-reduction
> >>
> >>>   published distributed solution.
> >>
> >>>   - mention of centralized solution asserting it is not good choice.
> >>
> >>>
> >>
> >>> - IETF 101 (Mar 2018)
> >>
> >>>   - Video:
> >> https://urldefense.proofpoint.com/v2/url?u=https-3A__www.youtube.com_
> >> watch-3Fv-3DqHmT4ytMn4w-26list-3DPLC86T-2D6ZTP5j-
> 5FHaBNdfP&d=DwICAg&c
> >> =HAkYuh63rsuhr6Scbfh0UjBXeMK-ndb3voDTXcWzoCI&r=CRB2tJiQePk0cT-
> h5LGhEW
> >> H-
> s_xXXup3HzvBSMRj5VE&m=kykK2jUejhafPHOrWXu0yvNk7XsXUoDYsWjFoFGHeT
> g&s
> >> =cBWxI4Hu1GZNWxuUZRREnZNg-cZZYbdrLHRXKsUama4&e=
> >> bgxGIp22cnaWS
> >>
> >>>   - Minutes:
> >> https://urldefense.proofpoint.com/v2/url?u=https-3A__datatracker.ietf
> >> .org_meeting_101_materials_minutes-2D101-2Dlsr-
> 2D00&d=DwICAg&c=HAkYuh
> >> 63rsuhr6Scbfh0UjBXeMK-ndb3voDTXcWzoCI&r=CRB2tJiQePk0cT-h5LGhEWH-
> s_xXX
> >>
> up3HzvBSMRj5VE&m=kykK2jUejhafPHOrWXu0yvNk7XsXUoDYsWjFoFGHeTg&s=
> 1UTDcj
> >> zO1b-Ful7k87ItzHcvqzRveIK_m_FI9eIDLFs&e=
> >>
> >>>   - draft-li-dynamic-flooding-02 presented (1 author). at IETF 101
> >>
> >>>     - Generally well received.
> >>
> >>>   - draft-cc-ospf-flooding-reduction-00 (4 authors) presented.
> >>
> >>>     - Serious problems immediately found during presentation -- not
> >> fully baked.
> >>
> >>>
> >>
> >>> - Mar 18, 2018 draft-li-dynamic-flooding-03 published (1 author)
> >>
> >>> - Mar 27, 2018 draft-li-dynamic-flooding-04 published (1 author)
> >>
> >>> - Apr 20, 2018 draft-cc-ospf-flooding-reduction-01 revised
> >>
> >>> - Jun 28, 2018 draft-li-dynamic-flooding-05 published (2 authors)
> >>
> >>>   - *SMALL CHANGE TO SUPPORT DISTRIBUTED ALGORITHM*.
> >>
> >>>   - Does not specify distributed algorithm only how to indicate one
> >>> in
> >> use, small change.
> >>
> >>>
> >>
> >>> - Jul 2, 2018 draft-cc-ospf-flooding-reduction-02 published
> >>
> >>>
> >>
> >>> - IETF 102 (Jul 14, 2018)
> >>
> >>>   - draft-li-dynamic-flooding-05 presented.
> >>
> >>>   - draft-cc-ospf-flooding-reduction-02 presented.
> >>
> >>>
> >>
> >>> - Sep 12, 2018 draft-cc-ospf-flooding-reduction-03 (4 authors)
> >>
> >>>   - *LARGE CHANGE ADDS NEW CENTRALIZED SOLUTION*.
> >>
> >>>
> >>
> >>> - Sep 20, 2018 draft-cc-ospf-flooding-reduction-04 (4 authors)
> >>
> >>>
> >>
> >>> - Oct 21, 2018 draft-li-lsr-dynamic-flooding-00 and -01 (5 authors)
> >>
> >>>
> >>
> >>> - IETF 103 (Nov 3, 2018)
> >>
> >>>
> >>
> >>>   - Chairs give direction
> >>
> >>>
> >>
> >>>     - draft-li-lsr-dynamic-flooding-05 having come first, being well
> >> written and not
> >>
> >>>       specifying a distributed algorithm (merely allowing for one)
> >>> is
> >> the correct vehicle
> >>
> >>>       to adopt as a base document.
> >>
> >>>
> >>
> >>>     - Distributed algorithm work (the original basis for
> >> draft-cc-ospf-flooding-reduction)
> >>
> >>>       should continue as a separate document form the base which
> >>> would
> >> thus we have no
> >>
> >>>       conflicts.
> >>
> >>>
> >>
> >>> - In the meantime the authors try and merge work, this fails.
> >>
> >>>
> >>
> >>> - Dec 3, 2018 draft-li-lsr-dynamic-flooding-02 (7 authors)
> >>
> >>>
> >>
> >>> - Dec 10, 2018 draft-cc-lsr-flooding-reduction-00 (4 authors)
> >>
> >>>
> >>
> >>> - Jan 7, 2019  draft-cc-lsr-flooding-reduction-01 (8 authors)
> >>
> >>
> >>
> >>
> >>
> >> _______________________________________________
> >> Lsr mailing list
> >> [e-mail]
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> >> lman_listinfo_lsr&d=DwICAg&c=HAkYuh63rsuhr6Scbfh0UjBXeMK-
> ndb3voDTXcWz
> >> oCI&r=CRB2tJiQePk0cT-h5LGhEWH-
> s_xXXup3HzvBSMRj5VE&m=kykK2jUejhafPHOrW
> >>
> Xu0yvNk7XsXUoDYsWjFoFGHeTg&s=BTZ1l1KpTxr_U3n0pZnknvuPBGxRM9ul08q
> CKpaE
> >> eXk&e=
> >>
> >
> > .
> >
> 
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