DomainKeys Identified Mail, or DKIM, is a method for validating the authenticity of an email using a digital signature. When DKIM is enabled for a given domain, a public key is published to the global DNS database and a private one is stored on the mail server. When a new email is sent, a signature is generated using the private key and when the email is received, the signature is checked by the incoming email server using the public key. In this way, the receiver can easily recognize if the email is genuine or if the sender’s address has been forged. A discrepancy will appear if the content of the email has been modified in the meantime as well, so DKIM can also be used to make sure that the sent and the received messages are identical and that nothing has been added or removed. This email authentication system will boost your email security, since you can validate the authenticity of the important emails that you get and your partners can do the same with the email messages that you send them. Depending on the given email service provider’s policies, a message that fails to pass the check may be deleted or may reach the recipient’s mailbox with a warning symbol.
