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Re: [TLS] The future of external PSK in TLS 1.3

Watson Ladd <watsonbladd@gmail.com> Wed, 30 September 2020 00:29 UTC

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From: Watson Ladd <watsonbladd@gmail.com>
Date: Tue, 29 Sep 2020 20:29:25 -0400
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To: "Blumenthal, Uri - 0553 - MITLL" <uri@ll.mit.edu>
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Subject: Re: [TLS] The future of external PSK in TLS 1.3
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On Tue, Sep 29, 2020 at 12:49 PM Blumenthal, Uri - 0553 - MITLL
<uri@ll.mit.edu> wrote:
>
> I share Achim's concerns.
>
> But I believe the explanations will turn out mostly useless in the real world, as the "lawyers" of the industry are guaranteed to steer away from something "not recommended".
>
> In one word: bad.

Why is PSK so necessary? There are very few devices that can't handle
the occasional ECC operation.  The key management and forward secrecy
issues with TLS-PSK are real. Steering applications that can afford
the CPU away from PSK and toward hybrid modes is a good thing and why
this registry exists imho.


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Astra mortemque praestare gradatim

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