Re: [dane] Use OPENPGPKEY or SMIMEA if both are available?

Viktor Dukhovni <ietf-dane@dukhovni.org> Mon, 09 March 2015 22:04 UTC

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Date: Mon, 09 Mar 2015 22:04:02 +0000
From: Viktor Dukhovni <ietf-dane@dukhovni.org>
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Subject: Re: [dane] Use OPENPGPKEY or SMIMEA if both are available?
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On Mon, Mar 09, 2015 at 10:21:15PM +0100, Patrick Ben Koetter wrote:

> Both, OPENPGPKEY and SMIMEA, carry the potential to increase wider usage of
> encryption. They offer a safe way for automated key distribution. All a sender
> will have to do is 'send' the message. Given appropriate software, MUA or MTA,
> will handle safe key retrieval and encrypt the message for any OPENPGPKEY and
> SMIMEA enabled recipient.

Pick whichever is also supported by the sender (for which the sender
also has a key).  If the sender has a key for both, I would have
historically gone with SMIME since more desktop clients support that.

However, things are changing, because smartphones have a new breed
of email clients, and I'm not sure which is more prevalent on iOS
and Android phones.  Also even if SMIME is more widely understood,
it is prone to raise warnings with self-signed or private CA issued
keys.  And we want to avoid such warnings.

So it is not yet clear which is to be preferred, in practice we
should be so lucky as to have to choose.  Most users have no keys
of either type.

-- 
	Viktor.