Generic Email Source: Related Servers


Absent any email authentication results, email sources can sometimes be related to an email stream if external factors are considered such as server reverse names and network ownership.

Possible Action

Legitimate email originating from "related servers" should be identified using SPF and DKIM. Leaving it up to receivers to identify legitimate email is suboptimal.


When deploying DMARC, domain owners often find new sources of email.

Domain owners then wonder if the source is capable of sending DMARC compliant email.

This directory contains information on the capabilities of various sources of email.