What is DMARC?
DMARC, which stands for “Domain-based Message Authentication, Reporting & Conformance”, is an email authentication, policy, and reporting protocol. It builds on the widely deployed SPF and DKIM protocols, adding linkage to the author (“From:”) domain name, published policies for recipient handling of authentication failures, and reporting from receivers to senders, to improve and monitor protection of the domain from fraudulent email.
Who Can Use DMARC?
DMARC policies are published in the public Domain Name System (DNS), and available to everyone. Because the specification is available with no licensing or similar restriction, any interested party is free to implement it.