DomainKeys Identified Mail, or DKIM, is a method for checking the legitimacy of an email by using a digital signature. When DKIM is enabled for a given domain, a public key is published to the global DNS system and a private one is kept on the mail server. When a new message is sent, a signature is generated using the private key and when the email message is received, that signature is verified by the POP3/IMAP server using the public key. In this way, the recipient can easily know if the email message is authentic or if the sender’s address has been forged. A mismatch will appear if the content of the email has been edited in the meantime as well, so DKIM can also be used to ensure that the sent and the received messages are identical and that nothing has been added or erased. This email authentication system will heighten your email safety, as you can verify the genuineness of the important email messages that you receive and your partners can do the same with the email messages that you send them. Depending on the given email provider’s adopted policies, an email that fails the test may be deleted or may end up in the receiver’s mailbox with a warning flag.
