Cybersecurity glossary
What is DKIM?
Also known as: DomainKeys Identified Mail
Definition
DKIM (DomainKeys Identified Mail) adds a cryptographic signature to outgoing email so receivers can verify it came from an authorized sender for the domain and was not altered in transit.
Why it matters
The sending service signs each message with a private key; the matching public key is published in DNS. DKIM alignment with the visible From domain is one of the ways a message can pass DMARC.
Common questions about DKIM
See also
Sources
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