DMARC

DMARC stands for Domain-based Message Authentication, Reporting, and Conformance (wow, that's a mouthful!) It's another tool available to combat spam, phishing and spoofing of your organization's email.

DMARC works with SPF and DKIM to check the authenticity of a message. If a message fails those authentication checks, DMARC allows you to tell the mails server what to do with those messages (this is called a receiver policy).

There are three different receiver policy options you can set with DMARC:

1. none: Take no action
2. quarantine: Mark as spam
3. reject: Do not deliver to recipients.