Email Auth
Table of Contents
A good source on SPF, DKIM and DMARC can be found here: https://docs.aws.amazon.com/ses/latest/dg/send-email-authentication-dmarc.html.
1. SPF
An SPF record is a kind of DNS text record which lists servers authorized to send emails from a given domain. It checks the domain of an email return-path (also known confusingly as bounce address, reverse path, envelope from, envelope sender, return address, and MAIL FROM) matches matches an IP in this given list.
A example round trip can be found in the How does a mail server check an SPF record? here.