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Re: [TLS] Simpler backward compatibility rules for 0-RTT

Bill Frantz <frantz@pwpconsult.com> Wed, 22 June 2016 00:30 UTC

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Date: Tue, 21 Jun 2016 17:30:21 -0700
From: Bill Frantz <frantz@pwpconsult.com>
To: Martin Thomson <martin.thomson@gmail.com>
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Subject: Re: [TLS] Simpler backward compatibility rules for 0-RTT
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On 6/22/16 at 5:24 PM, martin.thomson@gmail.com (Martin Thomson) wrote:

>To be clear about this, I expect that browsers will do some fairly
>horrific things in response to this.  We will attempt to use 0-RTT,
>get TLS 1.2 and abort as described.
>
>But then we will do the shameful thing and fall back to 1.2.  Plotting
>out the alternatives, I don't really see a better option.

Well, it seems like a browser could try TLS 1.3 without 0-RTT first.

If it connects with 1.3 non-0-RTT, then it could mark the host 
as not supporting 0-RTT for a day or so and after that time 
retry to see if the host has been fixed.

Cheers - Bill

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