Incoming SMTP in the year 2017 and absence of DKIM

Steve Atkins steve at
Thu Nov 30 17:03:24 UTC 2017

> On Nov 30, 2017, at 1:22 AM, Bjørn Mork <bjorn at> wrote:
> "John Levine" <johnl at> 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.


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