The tools used to enable email authentication have been around for a long time, but many companies still don’t understand what they do and why there is a need for them.
Some internet service providers (ISP’s) are getting stricter with authentication. Furthermore, the imminent changes in Google will mean that recipients will start getting warnings if senders have not set up their authentication properly.
I think it’s a good time to show you an infographic that explains it all.
For some additional information on email authentication have a look at these awesome links: