DMARC
Domain-based Message Authentication, Reporting, and Conformance
An email policy framework built on SPF and DKIM to fight spoofing.
DMARC builds on SPF and DKIM to tell receiving mail servers how to handle messages that fail authentication and to report results back to the domain owner. It adds alignment, requiring the visible From domain to match the authenticated domain, which closes spoofing gaps the other two leave open. Policies range from none for monitoring to quarantine or reject for enforcement. Together these three protocols form the standard defense against email spoofing and many phishing campaigns.
Tells receivers what to do when SPF or DKIM fail, and where to report. SPF and DKIM enforced by a DMARC policy.
Looking DMARC up is step one. Getting tested on it is step two.
A free account opens all 4 Domain 1 objectives, 271 exam-style questions with a lesson and a lab on each, a placement check that skips what you already know, and a dated plan. No card.
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