All You Need to Know About E-mail Authentication

DKIM is a cryptographic, signature-based type of e-mail authentication. DKIM is a combination of Yahoo’s DomainKeys (DK) and Cisco’s Identified Internet Mail (IIM). DKIM requires e-mail senders’ computers to generate “public/private key pairs” and then publishes the public keys in its DNS records. The matching private keys are stored in senders’ outbound e-mail servers, and when those servers send out e-mail, the private keys generate message-specific “signatures” that are added into additional, embedded e-mail headers.