DomainKeys Identified Mail, or DKIM, is a system for confirming the authenticity of an email message using an e-signature. When DKIM is enabled for a particular domain, a public encryption key is published to the global DNS database and a private one is kept on the mail server. When a new email message is sent, a signature is generated using the private key and when the message is delivered, the signature is ‘scanned’ by the incoming 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 forged. A mismatch will occur 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 attached or removed. This validation system will boost your email security, as you can confirm the authenticity of the important emails that you get and your colleagues can do likewise with the email messages that you send them. Depending on the given email service provider’s policy, a message that fails the examination may be deleted or may reach the recipient’s mailbox with a warning symbol.