Re: Incoming SMTP in the year 2017 and absence of DKIM

[Steve Atkins <steve () blighty com>]

> On Nov 30, 2017, at 1:22 AM, Bjørn Mork <bjorn () mork no> wrote:
>
> "John Levine" <johnl () iecc com> writes:
>
> > Broken rDNS is just broken, since there's approximately no reason ever
> > to send from a host that doesn't know its own name.
>
> rDNS is not a host attribute, and will therefore tell you exactly
> nothing about the host.

It tells you something about the competence of the operator and
whether the host is intended by the owners to send email.

Or, for a more empirical way to look at it, there's reasonable correlation
between having missing, generic or incorrect reverse DNS and the host
being a source of unwanted or malicious email.

Cheers,
  Steve