Cloudflare has announced the general availability of its DMARC Management tool, providing a free solution for organizations to monitor and enforce email authentication. DMARC (Domain-based Message Authentication, Reporting and Conformance) is an email authentication protocol that lets domain owners specify in DNS how receiving mail servers should handle messages that fail SPF and DKIM checks, helping prevent spoofing and phishing. SPF (Sender Policy Framework) checks whether the sending server is allowed to send mail for the domain, and DKIM (DomainKeys Identified Mail) uses a cryptographic signature to verify that the email’s content and claimed sender domain are authentic.
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