DomainKeys Identified Mail, or DKIM, is a method for confirming the genuineness of an email message by using an electronic signature. When DomainKeys Identified Mail is enabled for a certain domain, a public cryptographic key is published to the global DNS system and a private one is kept on the email server. When a new message is sent, a signature is generated using the private key and when the message is delivered, that signature is validated by the incoming mail server using the public key. In this way, the receiver can easily tell if the message is genuine or if the sender’s email address has been spoofed. A mismatch will occur if the content of the email has been altered in the meantime as well, so DomainKeys Identified Mail can also be used to ensure that the sent and the delivered email messages are identical and that nothing has been attached or deleted. This email authentication system will increase your email safety, as you can verify the authenticity of the important email messages that you get and your associates can do likewise with the email messages that you send them. Depending on the particular mail service provider’s policy, an email that fails to pass the examination may be deleted or may reach the receiver’s mailbox with a warning sign.
