DomainKeys Identified Mail, or DKIM, is a method for verifying the authenticity of an email by using an e-signature. When DKIM is activated for a specific domain name, a public encryption key is published to the global Domain Name System and a private one is kept on the email server. If a new email message is sent, a signature is generated using the private key and when the email is delivered, that signature is checked by the incoming POP3/IMAP email server using the public key. In this way, the recipient can easily distinguish if the email message is genuine or if the sender’s email address has been spoofed. A discrepancy will appear if the content of the email message has been edited in the meantime as well, so DKIM can also be used to make sure that the sent and the delivered emails are identical and that nothing has been attached or erased. This email authentication system will heighten your email security, since you can validate the legitimacy of the important emails that you get and your partners can do the exact same thing with the emails that you send them. Based on the particular mail service provider’s policies, an email message that fails to pass the test may be erased or may reach the recipient’s inbox with a warning notification.