Re: Fwd: New Version Notification for draft-duke-quic-v2-00.txt

[Martin Thomson <[e-mail]>]

Well you beat me to it.

Another nit to add to the pile: it might pay not to use 2 as the version number here.  Pick a random number, like 0xfaceb00c or something.

As for the labels we use for HKDF, tweaking those might be a good idea.  We didn't do that for draft versions, but a completely new version would benefit from better separation.

On Fri, Apr 23, 2021, at 03:52, Martin Duke wrote:
> Hello QUIC,
> 
> I believe it was MT that threatened to do this a long time ago, but to 
> work through compatible version negotiation I wrote up a trivial QUICv2 
> (below) that just changes the initial salts. This caused me to figure 
> out a couple of things about VN that may have been obvious to others 
> but not to me.
> 
> TL;DR we made the right decision to keep both in the draft.
> 
> 1. One very possible world is one where firewalls ossify on expecting 
> v1 in the first packet, but don't care about subsequent packets. 
> Compatible VN is well-designed for this world, as Client Initials (and 
> 0RTT, sadly) can be v1 essentially forever and subsequent packets can 
> be whatever we want.
> 
> 2. If all versions are compatible, choice of VN method is essentially 
> up to the client, but not quite deterministically: it can pick either a 
> likely supported version or an unlikely one. If unlikely, the server 
> will either accept it or send a VN. If likely, the server MUST use 
> compatible VN to change the version, since it can't send a VN packet 
> that contains the initial version unless it doesn't have full support 
> for it.
> 
> Anyway, this v2 draft is available for your consideration if people 
> want to quickly iterate a new version, and/or we need a vehicle for 
> fixes to v1.
> 
> Thanks
> Martin
> 
> 
> ---------- Forwarded message ---------
> From: <[e-mail]>
> Date: Thu, Apr 22, 2021 at 10:22 AM
> Subject: New Version Notification for draft-duke-quic-v2-00.txt
> To: Martin Duke <[e-mail]>
> 
> 
> 
> A new version of I-D, draft-duke-quic-v2-00.txt
> has been successfully submitted by Martin Duke and posted to the
> IETF repository.
> 
> Name:           draft-duke-quic-v2
> Revision:       00
> Title:          QUIC Version 2
> Document date:  2021-04-22
> Group:          Individual Submission
> Pages:          5
> URL:            https://www.ietf.org/archive/id/draft-duke-quic-v2-00.txt
> Status:         https://datatracker.ietf.org/doc/draft-duke-quic-v2/
> Html:           https://www.ietf.org/archive/id/draft-duke-quic-v2-00.html
> Htmlized:       https://tools.ietf.org/html/draft-duke-quic-v2-00
> 
> 
> Abstract:
>    This document specifies QUIC version 2, which is identical to QUIC
>    version 1 except for some trivial details.  Its purpose is to combat
>    various ossification vectors and exercise the version negotiation
>    framework.  Over time, it may also serve as a vehicle for needed
>    protocol design changes.
> 
>    Discussion of this work is encouraged to happen on the QUIC IETF
>    mailing list [e-mail] or on the GitHub repository which contains
>    the draft: https://github.com/martinduke/draft-duke-quic-v2.
> 
> 
> 
> 
> 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.
> 
> The IETF Secretariat
> 
>