Subject: I-D Action: draft-ietf-quic-version-negotiation-03.txt

From: [email-masked]
Date: Thu, 04 Feb 2021 16:34:56 -0800

A New Internet-Draft is available from the on-line Internet-Drafts directories.
This draft is a work item of the QUIC WG of the IETF.

        Title           : Compatible Version Negotiation for QUIC
        Authors         : David Schinazi
                          Eric Rescorla
	Filename        : draft-ietf-quic-version-negotiation-03.txt
	Pages           : 12
	Date            : 2021-02-04

Abstract:
   QUIC does not provide a complete version negotiation mechanism but
   instead only provides a way for the server to indicate that the
   version the client offered is unacceptable.  This document describes
   a version negotiation mechanism that allows a client and server to
   select a mutually supported version.  Optionally, if the original and
   negotiated version share a compatible first flight format, the
   negotiation can take place without incurring an extra round trip.

   Discussion of this work is encouraged to happen on the QUIC IETF
   mailing list [email-masked] (mailto:[email-masked]) or on the GitHub
   repository which contains the draft: https://github.com/quicwg/
   version-negotiation/ (https://github.com/quicwg/version-
   negotiation/).

The IETF datatracker status page for this draft is:
https://datatracker.ietf.org/doc/draft-ietf-quic-version-negotiation/

There is also an HTML version available at:
https://www.ietf.org/archive/id/draft-ietf-quic-version-negotiation-03.html

A diff from the previous version is available at:
https://www.ietf.org/rfcdiff?url2=draft-ietf-quic-version-negotiation-03

Please note that it may take a couple of minutes from the time of submission
until the htmlized version and diff are available at tools.ietf.org.

Internet-Drafts are also available by anonymous FTP at:
ftp://ftp.ietf.org/internet-drafts/

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From: David Schinazi <[email-masked]>
Date: Thu, 4 Feb 2021 16:44:47 -0800

Hi QUIC enthusiasts,

As you can see below, EKR and I have submitted an update to the version
negotiation draft.
This is a complete rewrite of the document, aiming at making the concepts
clearer. Please let
us know what you think and file issues, we'd love to get the discussion
started before IETF 110.

Thanks,
David

---

From: "Martin Thomson" <[email-masked]>
Date: Tue, 09 Feb 2021 16:42:23 +1100

Not an enthusiast, but I did read the draft.

Thanks for putting this together David.  I think that this is a lot clearer than previous versions about how it is structured.  I have opened a few issues and plan to open a few more.  There are some big open questions there unfortunately, but I am hopeful we can get through those.

On Fri, Feb 5, 2021, at 11:44, David Schinazi wrote:
> This is a complete rewrite of the document, aiming at making the 
> concepts clearer. Please let

---

From: Roberto Peon <[email-masked]>
Date: Tue, 9 Feb 2021 17:15:50 +0000

Pretty clear to me overall.

Optional Editorial:
    "Version compatibility is not bijective"
could also be stated as:
    "Version compatibility is not version equivalence"

One of the things that crosses my mind when reading through is that we don't address version switching, i.e. performing a version 'negotiation' while the previous connection's version is in use.

In particular, the draft doesn't describe if this is allowed or disallowed, and it isn't clear from other documents that version negotiation must happen only at the start of the connection-- there is not currently a 'must not' send a VN after connection established.
... probably good to clean that up one way or another.

-=R

On 2/8/21, 9:43 PM, "QUIC on behalf of Martin Thomson" <[email-masked] on behalf of [email-masked]> wrote: