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Re: [ietf-dkim] Smaller keys/Bigger privacy (was: Re: DKIM Key Sizes)

Jon Callas <jon@callas.org> Fri, 28 October 2016 05:36 UTC

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From: Jon Callas <jon@callas.org>
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Date: Thu, 27 Oct 2016 22:35:27 -0700
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References: <CAOj=BA3TFzxnHHZ+-tpoMCWxhaGvOg0RREbcYbpzS9g3g8i=Qg@mail.gmail.com> <33093A9D-5406-4BEF-AE65-66696B664593@callas.org> <8d87d35c-4dce-0827-0711-6809ac89b76f@bbiw.net>
To: Dave Crocker <dcrocker@gmail.com>
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Cc: ietf-dkim@mipassoc.org
Subject: Re: [ietf-dkim] Smaller keys/Bigger privacy (was: Re: DKIM Key Sizes)
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> On Oct 27, 2016, at 9:55 PM, Dave Crocker <dcrocker@gmail.com> wrote:
> 
> On 10/28/2016 12:29 AM, Jon Callas wrote:
>> The full discussion is pretty nuanced, and I think the relevant part here is that if an administrative domain wants to protect the privacy of its users, it should be using *smaller* DKIM keys, not larger ones. I think I could convincingly argue that a privacy-friendly email provider is better off using 512 bit keys (where there's a chance of spam forgery) than 4K keys (where there's a chance of ruining the privacy of the customers).
> 
> 
> Not just nuanced, but also counter-intuitive (at least to me)
> 
> It would be well worth having a stable pointer to a discussion that lays this out carefully and compellingly.

Okay. How should I do that?

	Jon


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