Re: [ietf-dkim] versions of RFC822 mail messages, Where is the formal definition of DKIM-Signature?

Dave Crocker <> Sat, 10 February 2018 17:22 UTC

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To: John Levine <>
References: <20180210155011.3735B1A7DD64@ary.qy>
From: Dave Crocker <>
Organization: Brandenburg InternetWorking
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Date: Sat, 10 Feb 2018 09:20:26 -0800
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Subject: Re: [ietf-dkim] versions of RFC822 mail messages, Where is the formal definition of DKIM-Signature?
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On 2/10/2018 7:50 AM, John Levine wrote:
> PS: The reason you haven't noticed the versions in RFC822 is that we
> put the version flags into SMTP.  An 8BITMIME or EAI mail message is
> not backward compatible with RFC822.

Well, that's simply and completely false.

The message format specification(s) have no dependency on the email 
transport mechanism.

In fact, you've tripped into the core debate that originally triggered 
the parallel, /competing/ efforts that produced ESMTP and MIME.


Dave Crocker
Brandenburg InternetWorking
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