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Re: [Uta] Eric Rescorla's Discuss on draft-ietf-uta-smtp-require-tls-07: (with DISCUSS and COMMENT)

"Alexey Melnikov" <aamelnikov@fastmail.fm> Wed, 13 March 2019 20:59 UTC

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Date: Wed, 13 Mar 2019 16:58:54 -0400
From: Alexey Melnikov <aamelnikov@fastmail.fm>
To: Eric Rescorla <ekr@rtfm.com>, The IESG <iesg@ietf.org>
Cc: uta@ietf.org, uta-chairs@ietf.org, Valery Smyslov <valery@smyslov.net>, draft-ietf-uta-smtp-require-tls@ietf.org
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Archived-At: <https://mailarchive.ietf.org/arch/msg/uta/GbL0uUW-eagCH9PD6eF4IcmFJXA>
Subject: Re: [Uta] Eric Rescorla's Discuss on draft-ietf-uta-smtp-require-tls-07: (with DISCUSS and COMMENT)
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Hi Ekr,

On Thu, Feb 21, 2019, at 3:07 PM, Eric Rescorla wrote:

> ----------------------------------------------------------------------
> DISCUSS:
> ----------------------------------------------------------------------
> 
> I support Benjamin's DISCUSS.
> 
> To elaborate on one point a bit: it seems to me that it's harmful to
> security to allow the sender to unilaterally override the recipient's
> preferences that something be encrypted. To forestall one argument,
> yes, the sender knows the contents of the message, but the recipient
> knows their own circumstances, and they may be at particular risk

I don't agree with this part of your DISCUSS and with your argument that this is the same as HSTS (I will try to gather my counter-arguments in a separate email), but in the interest of being constructive: can you suggest a possible fix (or directions towards the fix) to address your DISCUSS?

Thank you,
Alexey

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