Re: [ietf-smtp] DSNs

Dave Crocker <dhc@dcrocker.net> Sat, 25 April 2020 14:57 UTC

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To: Ned Freed <ned.freed@mrochek.com>, Viktor Dukhovni <ietf-dane@dukhovni.org>
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From: Dave Crocker <dhc@dcrocker.net>
Organization: Brandenburg InternetWorking
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Date: Sat, 25 Apr 2020 07:56:56 -0700
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Subject: Re: [ietf-smtp] DSNs
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On 4/25/2020 6:01 AM, Ned Freed wrote:
> Aside from implementation errors, I've seen no operational problems with DSNs,
> only with the DSN extension. The problem there is that some people have
> claimed that since NOTIFY=SUCCESS is a part of the base and they don't want to
> do it the only alternative is to disable the entire extension. I disagree; I
> think that since security concerns are paramount it's perfectly OK to simply
> reject NOTIFY=SUCCESS on security grounds.


Perhaps this goes to the challenge of a specification's distinguishing 
its essential core, versus desired-but-not-required enhancements.

Fail to support all of the core and it's not valid to claim to support 
the specification.

The danger of a pick-and-choose free-for-all is that a claim to support 
a specification provides little useful information.

d/
-- 
Dave Crocker
Brandenburg InternetWorking
bbiw.net