Re: [ietf-smtp] EHLO domain validation requirement in RFC 5321
Sam Varshavchik <mrsam@courier-mta.com> Sun, 27 September 2020 13:01 UTC
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From: Sam Varshavchik <mrsam@courier-mta.com>
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Date: Sun, 27 Sep 2020 09:01:36 -0400
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Subject: Re: [ietf-smtp] EHLO domain validation requirement in RFC 5321
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Keith Moore writes: > the fact that it works as a spam filter today seems like mere circumstance > or accident; I don't see any inherent reason that it will be a reliable spam > filter going into the future. Spammers do learn, if slowly, so if they > have to learn to make sure their EHLO arguments match their source IP > addresses, they'll do that. In the long term, I don't think this check > helps anything. Yes, I agree. Domain validation is not mainstream, but it is being use in practice, just enough to fall under the radar stream. If for any reason – whether explicitly blessed in an RFC or for any other reason – it becomes more prevalent then spam generators will certainly adopt. But at least right now it is a very effective filter. Like I wrote, this is really against my self-interest to bring more awareness to it.
- [ietf-smtp] EHLO domain validation requirement in… Sam Varshavchik
- Re: [ietf-smtp] EHLO domain validation requiremen… Keith Moore
- Re: [ietf-smtp] EHLO domain validation requiremen… Keith Moore
- Re: [ietf-smtp] EHLO domain validation requiremen… John Levine
- Re: [ietf-smtp] EHLO domain validation requiremen… Keith Moore
- Re: [ietf-smtp] EHLO domain validation requiremen… Sam Varshavchik
- Re: [ietf-smtp] EHLO domain validation requiremen… Sam Varshavchik
- Re: [ietf-smtp] EHLO domain validation requiremen… John R Levine
- Re: [ietf-smtp] EHLO domain validation requiremen… John C Klensin
- Re: [ietf-smtp] EHLO domain validation requiremen… Keith Moore
- Re: [ietf-smtp] EHLO domain validation requiremen… John R Levine
- Re: [ietf-smtp] EHLO domain validation requiremen… Keith Moore
- Re: [ietf-smtp] EHLO domain validation requiremen… Dave Crocker
- Re: [ietf-smtp] EHLO domain validation requiremen… Dave Crocker
- Re: [ietf-smtp] EHLO domain validation requiremen… Russ Allbery
- Re: [ietf-smtp] EHLO domain validation requiremen… John C Klensin
- Re: [ietf-smtp] EHLO domain validation requiremen… Keith Moore
- Re: [ietf-smtp] EHLO domain validation requiremen… Keith Moore
- Re: [ietf-smtp] EHLO domain validation requiremen… Keith Moore
- Re: [ietf-smtp] EHLO domain validation requiremen… Dave Crocker
- Re: [ietf-smtp] EHLO domain validation requiremen… Dave Crocker
- Re: [ietf-smtp] EHLO domain validation requiremen… Keith Moore
- Re: [ietf-smtp] EHLO domain validation requiremen… John R Levine
- Re: [ietf-smtp] EHLO domain validation requiremen… Ned Freed
- Re: [ietf-smtp] EHLO domain validation requiremen… John R Levine
- Re: [ietf-smtp] EHLO domain validation requiremen… Keith Moore
- Re: [ietf-smtp] EHLO domain validation requiremen… Dave Crocker
- Re: [ietf-smtp] EHLO domain validation requiremen… Sam Varshavchik
- Re: [ietf-smtp] EHLO domain validation requiremen… Claus Assmann
- Re: [ietf-smtp] EHLO domain validation requiremen… Keith Moore
- Re: [ietf-smtp] EHLO domain validation requiremen… Dave Crocker
- Re: [ietf-smtp] EHLO domain validation requiremen… Keith Moore
- Re: [ietf-smtp] EHLO domain validation requiremen… Sam Varshavchik
- Re: [ietf-smtp] EHLO domain validation requiremen… Keith Moore
- Re: [ietf-smtp] EHLO domain validation requiremen… Sam Varshavchik
- Re: [ietf-smtp] EHLO domain validation requiremen… Dave Crocker
- Re: [ietf-smtp] EHLO domain validation requiremen… Keith Moore
- Re: [ietf-smtp] EHLO domain validation requiremen… Keith Moore
- Re: [ietf-smtp] EHLO domain validation requiremen… John Levine
- Re: [ietf-smtp] EHLO domain validation requiremen… Keith Moore
- Re: [ietf-smtp] EHLO domain validation requiremen… Richard Clayton
- Re: [ietf-smtp] EHLO domain validation requiremen… Dave Crocker
- Re: [ietf-smtp] EHLO domain validation requiremen… Dave Crocker
- Re: [ietf-smtp] EHLO domain validation requiremen… Keith Moore
- Re: [ietf-smtp] EHLO domain validation requiremen… Sam Varshavchik
- Re: [ietf-smtp] EHLO domain validation requiremen… Keith Moore
- Re: [ietf-smtp] EHLO domain validation requiremen… Laura Atkins
- Re: [ietf-smtp] EHLO domain validation requiremen… Keith Moore
- Re: [ietf-smtp] EHLO domain validation requiremen… Laura Atkins
- Re: [ietf-smtp] EHLO domain validation requiremen… Keith Moore
- Re: [ietf-smtp] EHLO domain validation requiremen… Laura Atkins
- Re: [ietf-smtp] EHLO domain validation requiremen… Keith Moore
- Re: [ietf-smtp] EHLO domain validation requiremen… Laura Atkins
- Re: [ietf-smtp] EHLO domain validation requiremen… John Levine
- Re: [ietf-smtp] EHLO domain validation requiremen… Arnt Gulbrandsen
- Re: [ietf-smtp] EHLO domain validation requiremen… Keith Moore
- Re: [ietf-smtp] EHLO domain validation requiremen… Keith Moore
- Re: [ietf-smtp] EHLO domain validation requiremen… John Levine
- Re: [ietf-smtp] EHLO domain validation requiremen… Keith Moore
- Re: [ietf-smtp] EHLO domain validation requiremen… John R Levine
- Re: [ietf-smtp] EHLO domain validation requiremen… John R Levine
- Re: [ietf-smtp] EHLO domain validation requiremen… Mark Andrews
- Re: [ietf-smtp] EHLO domain validation requiremen… Mark Andrews
- Re: [ietf-smtp] EHLO domain validation requiremen… John R Levine
- Re: [ietf-smtp] EHLO domain validation requiremen… Keith Moore
- Re: [ietf-smtp] EHLO domain validation requiremen… Arnt Gulbrandsen
- Re: [ietf-smtp] EHLO domain validation requiremen… Sam Varshavchik
- Re: [ietf-smtp] EHLO domain validation requiremen… Richard Clayton
- Re: [ietf-smtp] EHLO domain validation requiremen… Keith Moore
- Re: [ietf-smtp] EHLO domain validation requiremen… Dave Crocker
- Re: [ietf-smtp] EHLO domain validation requiremen… Keith Moore
- Re: [ietf-smtp] EHLO domain validation requiremen… Keith Moore
- Re: [ietf-smtp] EHLO domain validation requiremen… Dave Crocker
- Re: [ietf-smtp] EHLO domain validation requiremen… Keith Moore
- Re: [ietf-smtp] EHLO domain validation requiremen… John Levine
- Re: [ietf-smtp] EHLO domain validation requiremen… Richard Clayton
- Re: [ietf-smtp] EHLO domain validation requiremen… Keith Moore
- Re: [ietf-smtp] EHLO domain validation requiremen… John Levine
- Re: [ietf-smtp] EHLO domain validation requiremen… Keith Moore
- Re: [ietf-smtp] EHLO domain validation requiremen… Sam Varshavchik
- Re: [ietf-smtp] EHLO domain validation requiremen… Keith Moore
- Re: [ietf-smtp] EHLO domain validation requiremen… Sam Varshavchik
- Re: [ietf-smtp] EHLO domain validation requiremen… Keith Moore
- Re: [ietf-smtp] EHLO domain validation requiremen… Sam Varshavchik
- Re: [ietf-smtp] EHLO domain validation requiremen… Keith Moore
- Re: [ietf-smtp] EHLO domain validation requiremen… Sam Varshavchik
- Re: [ietf-smtp] EHLO domain validation requiremen… Keith Moore
- Re: [ietf-smtp] EHLO domain validation requiremen… Alessandro Vesely
- Re: [ietf-smtp] own mail server: DNS / static IP … Claus Assmann
- Re: [ietf-smtp] own mail server: DNS / static IP … John Levine
- Re: [ietf-smtp] own mail server: DNS / static IP … Claus Assmann
- Re: [ietf-smtp] own mail server: DNS / static IP … Sam Varshavchik
- Re: [ietf-smtp] own mail server: DNS / static IP … Claus Assmann
- Re: [ietf-smtp] own mail server: DNS / static IP … Arnt Gulbrandsen
- Re: [ietf-smtp] own mail server: DNS / static IP … Ned Freed
- Re: [ietf-smtp] own mail server: DNS / static IP … John Levine
- Re: [ietf-smtp] own mail server: DNS / static IP … John Levine
- Re: [ietf-smtp] own mail server: DNS / static IP … Ned Freed
- Re: [ietf-smtp] own mail server: DNS / static IP … John R Levine
- Re: [ietf-smtp] own mail server: DNS / static IP … Ned Freed
- Re: [ietf-smtp] own mail server: DNS / static IP … Dave Crocker
- Re: [ietf-smtp] own mail server: DNS / static IP … John R Levine
- Re: [ietf-smtp] own mail server: DNS / static IP … Evert Mouw
- Re: [ietf-smtp] own mail server: DNS / static IP … Sam Varshavchik
- Re: [ietf-smtp] own mail server: DNS / static IP … Claus Assmann
- Re: [ietf-smtp] own mail server: DNS / static IP … Laura Atkins
- Re: [ietf-smtp] own mail server: DNS / static IP … Sam Varshavchik