Authentication
Email authentication
Technical methods (SPF, DKIM, DMARC) to verify that an email comes from its claimed sender.
Definition
Email authentication refers to the technical methods used to verify that an email legitimately comes from its claimed sender. The three main protocols are SPF (checking if the sending server is authorized), DKIM (cryptographic signature verification), and DMARC (policy framework combining both). Proper authentication is essential for deliverability and protecting your domain from spoofing.
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