Re: [ietf-smtp] EHLO domain validation requirement in RFC 5321

Arnt Gulbrandsen <arnt@gulbrandsen.priv.no> Mon, 28 September 2020 15:16 UTC

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From: Arnt Gulbrandsen <arnt@gulbrandsen.priv.no>
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Date: Mon, 28 Sep 2020 17:26:03 +0200
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Subject: Re: [ietf-smtp] EHLO domain validation requirement in RFC 5321
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On Monday 28 September 2020 16:27:58 CEST, John Levine wrote:
> Keith is asking us to expect that mail clients will move behind NAT64
> even while their associated servers do not, and that will happen
> enough that it will change a strong spam filtering signal. Doesn't
> seem likely to me.

For that to happen, someone has to say "well, I think that I'll change my 
mail server configuration to be more like a spammer" and then a million 
more people have to do the same, eventually weakening the spam signal. I 
fail to see why the first few thousand people would do any such thing.

It's a case where we can't get there from here, so debating whether "there" 
is a good place or not has no connection to reality. Please let's stop this 
now.

Arnt