How Does DKIM Work?

DKIM adds digital signatures to the headers of email messages which are then validated against public cryptographic keys in the organizational Domain Name System (DNS) records.

how does dkim work

The following steps are involved in the process:

  • Any outbound mail server sending an email generates a unique DKIM signature which is attached as a message header.
  • Inbound mail servers receiving these incoming emails scan the sender’s public DKIM keys in the DNS.
  • The inbound server decrypts the signature and compares it with a newly generated one using this public key.
  • If both values match, then the message is considered to be authentic and unaltered in transmission.