Subject: QUIC Version Negotiation Interim

From: Matt Joras <[email-masked]>
Date: Thu, 22 Apr 2021 11:34:03 -0700

Hello all,

As noted in previous mail, the draft minutes are available here[1]. A
high level summary of the meeting, as well as next steps, follows.

About 25 people attended and David kicked us off with a short update
as editor. Some of the attendees spoke briefly to the ideas that they
had shared to the list since the last meeting. Watson presented the
sketch of an alternative mechanism to achieve version negotiation to
the existing draft[2]. This design was very interesting and provoked
much discussion. There was, after a time, agreement that such a scheme
would likely require a change to the QUIC invariants. While not
strictly impossible there doesn't seem to be much motivation in this
direction or for making a change of that magnitude at this stage.

Much of the discussion focused on the notion of "compatible" versus
"incompatible" version negotiation and whether or not we require just
one, both, or neither. For definitions of these, please read sections
2 and 3 of the draft[2].

Regarding incompatible version negotiation, several people made
arguments that incompatible version negotiation is not needed in
practice today and we are unlikely to need it in the future. As the
main complexity of the current draft is mostly from incompatible
version negotiation, there is potentially a benefit from removing it
as a requirement.

On the other hand, many people felt strongly that incompatible version
negotiation is definitely a requirement and they can foresee use cases
for it. No one present strongly opposed a design which includes
incompatible version negotiation.

Similarly, some made the argument that compatible version negotiation
is also not a requirement. Nominally the same functionality is
achievable with a single QUIC version, transport parameters, and
extensions. There were many people who believe there is still value in
compatible version negotiation. No one present strongly opposed a
design which includes compatible version negotiation. There was a
general desire for clarity around when compatible versions should be
utilized versus simply specifying extensions.

To help get a sense of the room as the session was coming to an end,
the chairs took a show of hands for version negotiation requirement
options.

The chairs observed emerging consensus for supporting both compatible
and incompatible version negotiation. We also observed little interest
in alternatives to the design in the current draft[2]. Therefore the
proposal is to move ahead with the current draft and incorporate some
design improvements. Please comment if you disagree with this
proposal, the consensus call will last for one week until Thursday,
April 29th.

Thanks,
QUIC Chairs
Lars, Lucas, Matt

[1] https://github.com/quicwg/wg-materials/blob/main/interim-21-04/minutes.md
[2] https://tools.ietf.org/html/draft-ietf-quic-version-negotiation-03

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From: Marten Seemann <[email-masked]>
Date: Fri, 23 Apr 2021 09:05:37 +0700

Thank you for the summary. Is there a recording of the meeting? Would have
love to attend if it had been at a more suitable time.

On Fri, Apr 23, 2021 at 01:34 Matt Joras <[email-masked]> wrote:

> [1]
> https://github.com/quicwg/wg-materials/blob/main/interim-21-04/minutes.md

---

From: Lucas Pardue <[email-masked]>
Date: Fri, 23 Apr 2021 03:21:41 +0100

Hi Marten,

> love to attend if it had been at a more suitable time.

The meeting was held on WebEx and it was recorded. The secretariat kindly
publish these for us to YouTube and that can take up to 10 working days [1].

I'll make a note to reply here once I see the video go live on YouTube.

Cheers
Lucas

[1] -
https://mailarchive.ietf.org/arch/msg/wgchairs/wNMi_HNzIb_VqIA8z2OCxMhKj5c/

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From: "Martin Thomson" <[email-masked]>
Date: Fri, 23 Apr 2021 12:26:37 +1000

On Fri, Apr 23, 2021, at 12:21, Lucas Pardue wrote:
> The meeting was held on WebEx and it was recorded. The secretariat 
> kindly publish these for us to YouTube and that can take up to 10 
> working days [1].

If it does take that long, we should be prepared to extend the call here to allow for that.  That is, if Marten or others have reservations about the conclusion (that we met for 2 hours and decided that what we decided a while ago was OK).

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From: Matt Joras <[email-masked]>
Date: Thu, 22 Apr 2021 19:31:06 -0700

That's an excellent point, Martin. It looks like I am able to download
the recording manually. I will share that with Marten directly and
anyone else who requests it until it makes its way to Youtube.

Matt Joras

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From: Marten Seemann <[email-masked]>
Date: Fri, 23 Apr 2021 19:18:36 +0700

Matt shared the recording with me and I was able to watch it today. Thank
you for that.

In general, a processing time of 10 working days seems way too long to be
useful for people who want to actively participate in the work. Interim
meetings usually cause a lot of activity on the mailing list, and it's hard
to participate in a discussion if you know that you're missing all of the
context. After 10 working days, most discussions will most likely have
moved on or arrived at a conclusion.
Is there any better way we can come up with for future meetings? Sharing
the recording in a Google Drive wouldn't be a bad solution.

On Fri, Apr 23, 2021 at 9:27 AM Martin Thomson <[email-masked]> wrote:

> If it does take that long, we should be prepared to extend the call here
> to allow for that.  That is, if Marten or others have reservations about
> the conclusion (that we met for 2 hours and decided that what we decided a
> while ago was OK).
>
>

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From: Lucas Pardue <[email-masked]>
Date: Fri, 23 Apr 2021 13:37:52 +0100

Hi Marten,

> the recording in a Google Drive wouldn't be a bad solution.

I appreciate your points and agree.  Everything we can do to make the WG
participation as equivalent as possible is useful.

10 working days is an upper limit based on some factors outside the
secretariat control (such as how long it takes WebEx to present the
recording, how long YouTube encoding takes) and some factors in their
control (such as batching the manual work to upload). Mirja pointed out to
the chairs that we can request the secretariat to expedite the upload part,
so leave that with us.

Looking ahead, there is work going on that would allow interim meetings to
be held via MeetEcho. I'm not sure if that affects the turnaround time for
YouTube upload, so I've asked the question.

Cheers
Lucas

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From: Lucas Pardue <[email-masked]>
Date: Fri, 23 Apr 2021 16:14:06 +0100

Hello all,

The 2021-04-21 Interim session is now available on YouTube at
https://youtu.be/kmZwpbuhKjg

Many thanks to the secretariat for expediting this.

Cheers
Lucas