DomainKeys Identified Mail, or DKIM, is a system for confirming the authenticity of an email message using an electronic signature. When DKIM is enabled for a specific domain, a public cryptographic key is published to the global DNS database and a private one is stored on the email server. If a new message is sent, a signature is generated using the private key and when the email is delivered, the signature is authenticated by the POP3/IMAP server using the public key. Thus, the receiver can easily know if the message is authentic or if the sender’s address has been spoofed. A discrepancy will occur if the content of the email message has been changed in the meantime as well, so DomainKeys Identified Mail can also be used to ensure that the sent and the received emails are identical and that nothing has been added or removed. This email authentication system will heighten your email security, since you can confirm the legitimacy of the important emails that you receive and your colleagues can do the exact same thing with the email messages that you send them. Based on the particular email provider’s adopted policies, a message that fails to pass the check may be removed or may reach the recipient’s inbox with a warning alert.