DomainKeys Identified Mail, or DKIM, is a method for checking the genuineness of an email by using an electronic signature. When DomainKeys Identified Mail is enabled for a certain domain, a public key is published to the global DNS system and a private one is kept on the email server. When a new email message is sent, a signature is generated using the private key and when the message is delivered, that signature is verified by the POP3/IMAP server using the public key. Thus, the recipient can easily distinguish if the email is genuine or if the sender’s email address has been spoofed. A mismatch will appear if the content of the email message has been altered in the meantime as well, so DomainKeys Identified Mail can also be used to make sure that the sent and the delivered messages are identical and that nothing has been added or erased. This authentication system will boost your email security, as you can verify the legitimacy of the important email messages that you get and your associates can do likewise with the emails that you send them. Depending on the particular email provider’s policy, a message that fails to pass the examination may be erased or may reach the recipient’s inbox with a warning sign.