"Mark A. Lewis" <mark@xxxxxxxxxxxxxxxxx> writes:
> Lets say that Acme Widget has their mail hosted with Hostco. Acme Widget
> would rather not have mail.hostco.com in the mail headers for whatever
> reason. So, hostco doesn't setup a ptr record for it. This does not make
> Acme Widget or Hostco any more likely to be spammers, it just makes you
> more likely to drop their mail.
So they deliberately configure a non-compliant system, breaking the
rules for connecting to the Internet, as set down in the RFCs? Then
they will have problems sending email to a large number of sites, and
rightly so. They need to fix their misconfigured email system. This
is not a matter of opinion: they've set it up *wrong*.
Anyway, the point of checking that a system that's trying to deliver
email to you has a name that resolves to the address it's using, that
that address resolves back to the name, and that the HELO specifies
the correct name as well, is that most privately owned Windows PCs
don't fulfill those requirements. So, when they're infected with
viruses that turn them into remote controlled, spam-sending robots,
your email system can refuse to even talk to them. Please note that
this is by far the major technique for distributing spam these days,
and has turned into a huge business, where people who create viruses
earn big money renting out zombie networks to spammers and other
criminal scum.
-tih
--
Don't ascribe to stupidity what can be adequately explained by ignorance.
