Re: Key updates

Martin Thomson <martin.thomson@gmail.com> Tue, 07 August 2018 00:39 UTC

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From: Martin Thomson <martin.thomson@gmail.com>
Date: Tue, 07 Aug 2018 10:39:23 +1000
Message-ID: <CABkgnnW1VhCKc+SDTGLJ0Q4BZZz9jJLmv3nOPrGTWWJe-dHTvg@mail.gmail.com>
Subject: Re: Key updates
To: Mirja Kühlewind <mirja.kuehlewind@tik.ee.ethz.ch>
Cc: Ian Swett <ianswett=40google.com@dmarc.ietf.org>, QUIC WG <quic@ietf.org>
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On Mon, Aug 6, 2018 at 11:06 PM Mirja Kühlewind
<mirja.kuehlewind@tik.ee.ethz.ch> wrote:
> However, this brings us back to Martin’s other question: does it make sense to have a couple of reserved bits to make it easy to add a bit for the next version with minimal changes to the protocol machinery/wire image?

I think that was Dirkjan who asked that question.

The driving principle behind defining invariants was to avoid having
to come back to this question repeatedly.  We have a version
negotiation mechanism that allows us to change an awful lot between
different protocol version.  We don't need to reserve a few bits
because most of them are already reserved.