- SPF (Sender Policy Framework): a framework used to prevent e-mail forgery aka Spoofing. Spoofing is when someone is pretending to be sent from your e-mail address.
- DKIM (DomainKeys Identified Mail): This will allow a server to send e-mails in your name while being authenticated to make sure it’s really you. For example, if you use MailChimp or ConstantContact for newsletter blasts and say it’s from ‘firstname.lastname@example.org’, the e-mails will still be sent from MailChimp or ConstantContacts server. However, you verified with your Blast e-mail service that is indeed you and not someone pretending to be you. This is the most important one to set up correctly for businesses, as otherwise there will be a high bounce-back rate!
- DMARC (Domain-based Message Authentication, Reporting, and Conformance): Also an Anti-Spoofing mechanism that will work in conjunction with SPF. Having one or the other is ineffective — you will need both to be properly protected.
A thorough helpful read on the benefits of authenticating and securing your outbound email if you use your own domain. It's well worth reviewing and implementing all of these records and policies if you have not done so already.