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Re: [TLS] Remove DH-based 0-RTT

Martin Thomson <martin.thomson@gmail.com> Tue, 23 February 2016 19:38 UTC

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Date: Tue, 23 Feb 2016 11:38:30 -0800
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From: Martin Thomson <martin.thomson@gmail.com>
To: Wan-Teh Chang <wtc@google.com>
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Subject: Re: [TLS] Remove DH-based 0-RTT
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On 23 February 2016 at 11:24, Wan-Teh Chang <wtc@google.com> wrote:
> It seems sufficient to just ban client authentication in replayable
> DH-based 0-RTT. Why remove DH-based 0-RTT altogether?

On the grounds that it is more complex to analyze, build, and test.
And given that deferring the feature does no significant harm to those
who want it.

I acknowledge that persistence of secrets on clients is a material
difference between that an PSK-based 0-RTT.  I just don't think that
it's a good enough reason to pay for what is a relatively expensive
feature.

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