DomainKeys Identified Mail

DomainKeys Identified Mail, or DKIM, is a system for confirming the authenticity of an email message using a digital signature. When DomainKeys Identified Mail is activated for a given domain name, 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 issued using the private key and when the message is received, that signature is ‘scanned’ by the incoming mail server using the public key. Thus, the receiver can easily discern if the email is genuine or if the sender’s email address has been forged. A discrepancy will appear if the content of the email message has been altered on its way as well, so DKIM can also be used to make sure that the sent and the delivered messages are identical and that nothing has been added or removed. This authentication system will increase your email security, since you can confirm the legitimacy of the important email messages that you receive and your partners can do the exact same thing with the emails that you send them. Depending on the given email service provider’s adopted policy, a message that fails to pass the test may be removed or may reach the recipient’s inbox with a warning alert.