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Re: [TLS] Supported Versions extension

Eric Rescorla <ekr@rtfm.com> Mon, 17 October 2016 20:43 UTC

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From: Eric Rescorla <ekr@rtfm.com>
Date: Mon, 17 Oct 2016 16:42:39 -0400
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To: Brian Smith <brian@briansmith.org>
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Subject: Re: [TLS] Supported Versions extension
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On Mon, Oct 17, 2016 at 4:40 PM, Brian Smith <brian@briansmith.org> wrote:

> Ilari Liusvaara <ilariliusvaara@welho.com> wrote:
>
>> Omitting TLS 1.2 causes failures in some downnegotiation cases (when there
>> are higher versions supported, but not overlapping).
>>
>
> Could you provide a concrete example, please?
>

When I support TLS 1.2 and TLS 1.3 draft-16 and you support TLS 1.2 and TLS
1.3 draft-17.

I would prefer to stick with the current design where if supported_versions
exists it is the sole
mechanism for negotiation.

-Ekr


Thanks,
> Brian
> --
> https://briansmith.org/
>
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