Re: Rechartering QUIC for Post Version 1 Work

[Roberto Peon <[e-mail]>]

Another interesting one..

If did partially-reliable HTTP (which would absolutely require QUIC stuff), where would that live?
-=R

From: QUIC <[e-mail]> on behalf of David Schinazi <[e-mail]>
Date: Tuesday, January 26, 2021 at 5:21 PM
To: Lucas Pardue <[e-mail]>
Cc: IETF QUIC WG <[e-mail]>
Subject: Re: Rechartering QUIC for Post Version 1 Work

Thanks for your reply, Lucas. Responses inline.

On Tue, Jan 26, 2021 at 4:56 PM Lucas Pardue <[e-mail]<mailto:[e-mail]>> wrote:
Hi David,

Thanks for the feedback. I've responded in-line, and some of that text responds to points Ian raised too.

On Tue, Jan 26, 2021 at 9:54 PM David Schinazi <[e-mail]<mailto:[e-mail]>> wrote:
I'm supportive of the overall direction of this rechartering, with some concerns though:

1) multipath is not mentioned in this charter - based on the conversations we've had over the past months, I think we should be explicit about whether multipath is in or out of scope

The intention was that the new charter would allow the group, as the focal point for QUIC-related things, to consider work such as multipath QUIC. The guidance for discussion of multipath is still the same as Lars' sent to the WG in November [1]. To borrow a bit of that, we still feel it premature to adopt an proposal as a work item.

I see your point, I'm OK with not precluding multipath as long as the guidance from November still holds. But then again, a recharter could be seen as invalidating prior charter-related decisions so being explicit could be useful here.

There's an interesting contrast between this point and your second point. It seems there's a balance between being specific and appearing not open to new ideas.

From my perspective, multipath was important enough of a topic to warrant its own interim a few months back which isn't true of any of our extensions - so I guess that's where I'd draw the line in terms of mentioning something or not?

2) +1 to Ian and Dmitri's comments about mentioning current examples in a way that seems to preclude other extensions, we could remove the examples to help clarify

(previously I commented as an individual, but now with a chair hat on) If 3 people have the same comment, it's likely a sign that some polishing up of the text would help. Specific suggestions always appreciated.

I liked Dmitri's proposal to remove the examples. If we want to include examples that are in scope, I'd suggest also including examples of what's not in scope to make it clear that neither list is exhaustive.

3) I was surprised by "Extensions intended for Standards Track need to have general applicability to multiple application protocols." and I don't think our charter should preclude these. We shouldn't ban standard-track protocols that require a QUIC extension to function properly. Perhaps another way we could phrase this would be to say that "The QUIC WG is only chartered to work on extensions that have general applicability to multiple application protocols. Extensions that are specific to an application protocol should be defined in the WG responsible for that protocol, in consultation with the QUIC WG." -- without stating anything about Standards track.

I'd like Lars or Magnus to respond to this point too. IIUC the intention of the text is to say that QUIC transport extensions that wish to be adopted by this group under Standards Track, should apply broadly. An extension designed for only one specific use, and which the authors do not wish to spend time considering design changes that would permit more-general usage, isn't a great use of the WGs time trying to standardise. However, the QUIC WG is a good venue to catalog such work as Informational or Experimental. I don't believe we want to prevent QUIC extensions that are specific to a use from being developed as Standards Track elsewhere in the IETF.

I love bikeshedding document tracks as much as the next person, but I don't think that needs to be litigated in the charter - the charter should help us decide what we allocate WG time for - if an extension is not seen as valuable by the WG, I don't think it's worth it to spend WG time to publish it as experimental or informational. Either we care about the extension or we don't, right?

4) It seems off to me to simultaneously declare HTTP/3 logging in-scope and HTTP/3 out-of-scope. I think qlog is useful, but if we want to use it outside of the QUIC transport protocol then maybe it should live in another WG.

That's one (fair) interpretation. The intent here is to make it clear that the QUIC WG no longer owns the HTTP/3 application mapping, as always intended. qlog doesn't change protocols so working on that falls into the deployment working area. I expect a large part of the QUIC WG population, to start with, will be made up of deployers of HTTP/3. So while there has been some discussion on the most suitable home for qlog and splitting the drafts up [2], keeping them developed in a single WG would seem like the best way to channel effort and attention of active deployers. If others have a strong sense that is not the case they should speak up.

Members of the QUIC implementers community have been attending other QUIC-adjacent working groups, so I don't think placing them in QUIC will impact implementation energy. I'd even argue that placing these in QUIC might constrain them to QUIC instead of also encouraging other protocols. If someone were to write a draft about how to use qlog with SCTP, would it belong in the QUIC WG?

5) "Maintenance and evolution of the QUIC base specifications" isn't very clear to me - does that mean that working on future versions of QUIC is in or out of scope?

The full paragraph states:

" Maintenance and evolution of the QUIC base specifications that describe its invariants, core transport mechanisms, security and privacy, loss detection and recovery, congestion control, version and extension negotiation, etc. This includes the specification of new versions of QUIC, if necessary."

I think that's clear but if you have some suggestions to improve it we'll take a look.

Nope, that is very clear - I must have missed it which is my fault. Apologies.

But now I'm realizing that the "if necessary" in that last sentence might be interpreted differently by various folks when we start wondering what features should go into QUIC v2. I'd suggest just removing the "if necessary".

David

Cheers,
Lucas

[1] - https://mailarchive.ietf.org/arch/msg/quic/rcPf7u9AHIGwNr6j0ZqrqFujVvk/<https://mailarchive.ietf.org/arch/msg/quic/rcPf7u9AHIGwNr6j0ZqrqFujVvk/>
[2] - https://mailarchive.ietf.org/arch/msg/quic/yv9FFyXItsKK6m-5I5eRE6jnqR8/<https://mailarchive.ietf.org/arch/msg/quic/yv9FFyXItsKK6m-5I5eRE6jnqR8/>