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Re: [ietf-smtp] SMTP Over TLS on Port 26 - Implicit TLS Proposal

Paul Smith <paul@pscs.co.uk> Mon, 07 January 2019 12:15 UTC

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From: Paul Smith <paul@pscs.co.uk>
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Date: Mon, 07 Jan 2019 12:08:48 +0000
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Subject: Re: [ietf-smtp] SMTP Over TLS on Port 26 - Implicit TLS Proposal
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On 07/01/2019 12:03, Jeremy Harris wrote:
> On 07/01/2019 11:34, Paul Smith wrote:
>> A simple TXT record saying "This domain's MTAs support STARTTLS (and,
>> possibly, optionally, this is the certificate fingerprint)" would seem
>> useful and not need anything else, and would protect against STARTTLS
>> downgrade for any sender willing to support it.
> Starting to look like a DANE TLSA record...

Yep - but without needing DNSSEC, which seems to be the OP's problem 
with DANE.



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