DKIM (DomainKeys Identified Mail) is one of the two email authentication protocols used in DMARC (Domain-based Message Authentication Reporting and Conformance), the other being SPF (Sender Policy Framework). DKIM provides a digital signature for each email, verifying that it was sent by an authorized sender and has not been altered in transit. The DKIM signature is verified by the recipient’s email server, and if the signature matches, the email is deemed authentic. DMARC builds on DKIM and SPF by providing a policy mechanism that tells receiving email servers how to treat emails that fail authentication checks. In DMARC, DKIM plays a critical role in helping domain owners protect their domain’s reputation and prevent email fraud and abuse.
