Re: [dane] Improving DANE S/MIME Privacy

Viktor Dukhovni <ietf-dane@dukhovni.org> Tue, 11 April 2017 18:52 UTC

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From: Viktor Dukhovni <ietf-dane@dukhovni.org>
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Subject: Re: [dane] Improving DANE S/MIME Privacy
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> On Apr 11, 2017, at 1:38 PM, Viktor Dukhovni <ietf-dane@dukhovni.org>; wrote:
> 
> If the design were up to me, I'd not have published per-user keys.
> Instead a site-wide trust-anchor record scales better to large user
> communities, and mostly addresses your concerns.

I should note that one can of course implement one's SMIMEA deployment
in exactly this way, something along the lines of:

   *._smimecert.example.net. IN SMIMEA 2 1 1 e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855

would associate the same TA public key digest with every user, and would
not enable user enumeration.

-- 
	Viktor.