Re: [Asrg] What are the IPs that sends mail for a domain?

Steve Atkins <steve@blighty.com> Sat, 20 June 2009 23:22 UTC

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Date: Sat, 20 Jun 2009 16:22:37 -0700
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Subject: Re: [Asrg] What are the IPs that sends mail for a domain?
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On Jun 20, 2009, at 4:06 PM, David Nicol wrote:

> On Sat, Jun 20, 2009 at 2:20 PM, Alessandro Vesely<vesely@tana.it>  
> wrote:
>> However, in practice one needs an email address to do any  
>> legitimate use of
>> SMTP, and hence a domain is required.
>
> There isn't any technical reason why MUA software can't do its own
> delivery with today's technology.  The whole concept of "outbound MTA"
> seems like a throwback. With the exception of delivery delays, but
> having a MUA attempt its own delivery and then switch to the smarthost
> on connection or other temporary failure wouldn't require any
> inspiration.

Just a terminology / architecture comment...

It'd be perfectly possible to build a mail client that behaved that way
(and people have, I think), or setup a system that works in that way
using existing components (and many people do).

But I'd claim that that mail client is then behaving as both an MUA and
an MTA (and probably an MSA too).

It's useful to draw a distinction between the architectural roles, even
when the roles are performed by the same executable.

http://www.bbiw.net/specifications/draft-crocker-email-arch-14.html
is worth a read, ideally with a drink close to hand, for lots of
terminology discussion.

Cheers,
   Steve