DomainKeys Identified Mail, or DKIM, is a system for confirming the legitimacy of an email message using an electronic signature. When DomainKeys Identified Mail is enabled for a given domain name, a public key is published to the global DNS database and a private one is stored on the mail server. When a new email message is sent, a signature is generated using the private key and when the email is delivered, the signature is verified by the POP3/IMAP mail server using the public key. In this way, the recipient can easily tell if the message is authentic or if the sender’s email address has been spoofed. A discrepancy will appear if the content of the email message has been modified on its way as well, so DomainKeys Identified Mail can also be used to ensure that the sent and the delivered emails are identical and that nothing has been added or deleted. This email validation system will heighten your email security, as you can confirm the genuineness of the important emails that you get and your partners can do the exact same thing with the emails that you send them. Depending on the particular email provider’s policy, a message that fails the test may be deleted or may appear in the receiver’s inbox with a warning notification.
