DMARCrecord

A DMARC record, which stands for Domain-based Message Authentication, Reporting, and Conformance, is a TXT record published in a domain's DNS settings. Its primary purpose is to help prevent email spoofing and phishing attacks by providing a framework for domain owners to specify how their email should be handled if it fails authentication checks.

The DMARC record works in conjunction with two other email authentication protocols: SPF (Sender Policy Framework) and DKIM (DomainKeys Identified Mail). SPF verifies that an email originated from an IP address authorized by the domain owner, while DKIM cryptographically signs outgoing emails to verify their authenticity and integrity. DMARC ties these together, allowing domain owners to define a policy that dictates what receivers should do with emails that fail SPF and DKIM checks.

There are three main DMARC policies: "none," "quarantine," and "reject." A "none" policy means no action is taken, but reports are still sent. "Quarantine" suggests that suspicious emails should be sent to the spam folder. "Reject" instructs receiving servers to outright reject emails that fail authentication.

In addition to setting policies, DMARC records also enable reporting. Domain owners can specify email addresses to receive aggregate and forensic reports detailing the authentication results of emails sent from their domain. These reports are invaluable for identifying potential abuse and troubleshooting authentication issues, ultimately enhancing email security and deliverability.