§2024-11-02
DMARC, which stands for Domain-based Message Authentication, Reporting & Conformance, is an email authentication protocol designed to help prevent email spoofing and phishing attacks. It builds on two existing technologies: SPF (Sender Policy Framework) and DKIM (DomainKeys Identified Mail).
- Here’s how DMARC works:
- Authentication: DMARC checks whether incoming emails from a domain are properly authenticated using SPF and DKIM. SPF verifies that the sending server is allowed to send emails on behalf of the domain, while DKIM ensures the email content hasn’t been tampered with.
- Policy Definition: Domain owners publish a DMARC policy in their DNS records, specifying how email receivers should handle messages that fail authentication checks. The policy can be set to:
- none: No specific action is taken, but reports are sent.
- quarantine: Emails that fail the checks should be treated as suspicious and placed in the spam or junk folder.
- reject: Emails that fail the checks should be outright rejected.
- Reporting: DMARC provides a reporting mechanism that allows domain owners to receive feedback on their email authentication status. This can include information about successful and failed authentication attempts, which helps in monitoring and improving email security.
By implementing DMARC, organizations can protect their domains from being misused by attackers, enhance email deliverability, and gain better visibility into their email traffic.