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Re: [ietf-smtp] on liberality, was MTS-STS_validation

Dave Crocker <dhc@dcrocker.net> Sun, 04 April 2021 21:17 UTC

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Reply-To: dcrocker@bbiw.net
To: ietf-smtp@ietf.org
References: <20210404211320.5302671FB8BC@ary.qy>
From: Dave Crocker <dhc@dcrocker.net>
Organization: Brandenburg InternetWorking
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Date: Sun, 04 Apr 2021 14:17:28 -0700
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Subject: Re: [ietf-smtp] on liberality, was MTS-STS_validation
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On 4/4/2021 2:13 PM, John Levine wrote:
> One could read the standard either way,

The above is an example of the essential requirement to Postel's 
directive.  In the face of possible ambiguity in how a standard is 
interpreted, try to be conservative in what you send and try to be 
liberal in what you accept.

Absent that kind of contextual constraint, the directive produces 
non-interoperability.

d/

-- 
Dave Crocker
Brandenburg InternetWorking
bbiw.net

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