Re: [ietf-smtp] DSNs
John C Klensin <john-ietf@jck.com> Sat, 25 April 2020 22:15 UTC
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Date: Sat, 25 Apr 2020 18:15:04 -0400
From: John C Klensin <john-ietf@jck.com>
To: Ned Freed <ned.freed@mrochek.com>, Dave Crocker <dhc@dcrocker.net>
cc: ietf-smtp@ietf.org, Viktor Dukhovni <ietf-dane@dukhovni.org>
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References: <20200409230011.F039B17637D0@ary.qy> <alpine.OSX.2.22.407.2004091945050.80689@ary.qy> <20200410090430.GA75736@kiel.esmtp.org> <29104A0F-B9ED-4CD7-99B3-5A042375C68B@dukhovni.org> <r7fq4k$1nm5$1@gal.iecc.com> <C1A5FAAA942E0F363CA177C0@PSB> <20200425013624.GV41308@straasha.imrryr.org> <01RK47G4QUK0000058@mauve.mrochek.com> <22e05a3b-bf47-9d83-a340-720ca9a373c4@dcrocker.net> <01RK4LP3NYJK000058@mauve.mrochek.com>
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Subject: Re: [ietf-smtp] DSNs
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--On Saturday, April 25, 2020 14:15 -0700 Ned Freed <ned.freed@mrochek.com> wrote: [...] >> Perhaps this goes to the challenge of a specification's >> distinguishing its essential core, versus >> desired-but-not-required enhancements. > > Completely inapplicable in this case, I'm afraid. One of the > primary goals of > the NOTARY effort, if not the primary goal, was feature parity > with X.400. > And the operational model for X.400 was success receipts as > the default. > > So the feature had to be part of the core. > But thinkgs change. X.400 collapsed - a casualty of even more > serious > design errors than success DSNs. Spam became email's biggest > problem, > which made NOTIFY=SUCCESS less desirable. Privacy concerns > also arose that > weren't even on the radar at the time this work was done. > >> Fail to support all of the core and it's not valid to claim >> to support the specification. > > It's not a question of support, it's a question of operational > policy. Every > implementation of the DSN extension I've seen has no problem > supporting > NOTIFY=SUCCESS. THe debate has been over whether or not it's > legitimate to have > an operational policy of bouncing messages that ask for it. > > Of course there's also the issue of whether or not the > extension, eith > or without NOTIFY=SUCESS, is of sufficient value to enable. > Some people > see little value here, and the NOTIFY=SUCCESS situation is > sufficiently > bothersome to tip the scale to dropping the extension. > >> The danger of a pick-and-choose free-for-all is that a claim >> to support a specification provides little useful information. > > Dave, we're talking about having an operational policy of > restricing the use of > exactly one feature which made sense when the standard was > defined but has > issues today. This is hardly a pick-and-choose free-for-all. Agreed. And FWIW, it seems to me that much, if not most, of this discussion is not about whether a feature can be implemented, has been implemented, or interoperates but about a potentially useful (but so far non-existent, at least in the IETF) document that says "it would be a good idea to enable feature A if circumstances and considerations X apply and to not do so if circumstances and conditions Y apply". Even if either X or Y exist all the time or are null, that sort of statement would likely be useful. And that is a suggestion for an Applicability Statement, one that I hope someone who cares will start writing, not a fundamental flaw or error in the Technical Specifications. Just my opinion, of course. john
- [ietf-smtp] SMTP, DSNs, and enhanced replies (was… John C Klensin
- Re: [ietf-smtp] SMTP, DSNs, and enhanced replies … Hector Santos
- Re: [ietf-smtp] SMTP, DSNs, and enhanced replies … Dave Crocker
- Re: [ietf-smtp] SMTP, DSNs, and enhanced replies … Brandon Long
- Re: [ietf-smtp] SMTP, DSNs, and enhanced replies … John Levine
- Re: [ietf-smtp] SMTP, DSNs, and enhanced replies Dave Crocker
- Re: [ietf-smtp] SMTP, DSNs, and enhanced replies John R Levine
- Re: [ietf-smtp] SMTP, DSNs, and enhanced replies … Ned Freed
- Re: [ietf-smtp] SMTP, DSNs, and enhanced replies Ned Freed
- Re: [ietf-smtp] SMTP, DSNs, and enhanced replies Jeremy Harris
- Re: [ietf-smtp] DSNs Claus Assmann
- Re: [ietf-smtp] DSNs Viktor Dukhovni
- Re: [ietf-smtp] DSNs John Levine
- Re: [ietf-smtp] DSNs John C Klensin
- Re: [ietf-smtp] DSNs John Levine
- Re: [ietf-smtp] DSNs Alessandro Vesely
- Re: [ietf-smtp] DSNs Viktor Dukhovni
- Re: [ietf-smtp] DSNs Ned Freed
- Re: [ietf-smtp] DSNs Dave Crocker
- Re: [ietf-smtp] DSNs Viktor Dukhovni
- Re: [ietf-smtp] DSNs Dave Crocker
- Re: [ietf-smtp] DSNs Ned Freed
- Re: [ietf-smtp] DSNs Dave Crocker
- Re: [ietf-smtp] DSNs Jeremy Harris
- Re: [ietf-smtp] DSNs John C Klensin
- Re: [ietf-smtp] DSNs Scott Kitterman
- Re: [ietf-smtp] DSNs John C Klensin
- [ietf-smtp] Variable HELO name, was DSNs Alessandro Vesely
- Re: [ietf-smtp] DSNs Arnt Gulbrandsen
- Re: [ietf-smtp] Variable HELO name, was DSNs Ned Freed
- Re: [ietf-smtp] Variable HELO name, was DSNs John C Klensin
- Re: [ietf-smtp] DSNs John C Klensin
- Re: [ietf-smtp] DSNs Dave Crocker
- Re: [ietf-smtp] DSNs Ned Freed
- Re: [ietf-smtp] DSNs Viktor Dukhovni
- Re: [ietf-smtp] DSNs John Levine
- Re: [ietf-smtp] DSNs Sam Varshavchik
- Re: [ietf-smtp] DSNs Valdis Kl ē tnieks
- Re: [ietf-smtp] DSNs Scott Kitterman
- Re: [ietf-smtp] DSNs John Levine
- Re: [ietf-smtp] DSNs Sam Varshavchik
- Re: [ietf-smtp] DSNs Valdis Kl ē tnieks
- Re: [ietf-smtp] DSNs Laura Atkins
- Re: [ietf-smtp] DSNs Sam Varshavchik
- Re: [ietf-smtp] DSNs John Levine
- Re: [ietf-smtp] DSNs Sam Varshavchik
- Re: [ietf-smtp] DSNs John Levine
- Re: [ietf-smtp] DSNs Sam Varshavchik
- Re: [ietf-smtp] DSNs Ned Freed
- Re: [ietf-smtp] DSNs Viktor Dukhovni
- Re: [ietf-smtp] DSNs Sam Varshavchik