Re: [quicwg/base-drafts] Describe a new version negotiation mechanism which allows for (#1755)

Mike Bishop <notifications@github.com> Fri, 28 September 2018 16:39 UTC

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Subject: Re: [quicwg/base-drafts] Describe a new version negotiation mechanism which allows for (#1755)
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I think preference is always in the hands of the one who switches, with ability to constrain options on the other party.  So I'd frame it as:
- Client begins with the version it thinks is most likely to be supported
- Includes a list of compatible versions it considers equally-or-more preferred
- Server either chooses the most preferred from the set of (used, offered), or sends VN if there's no overlap
- Client learns from VN or the transport parameters the set of versions the server is offering; if it sees something it likes better, it remembers to offer that in the future.

There's not necessarily an obligation to disclose every version you're capable of speaking; you might only disclose the ones you want a peer to use.

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