DomainKeys Identified Mail

DomainKeys Identified Mail, or DKIM, is a system for verifying the legitimacy of an email using a digital 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. If a new email message is sent, a signature is generated using the private key and when the email message is received, that signature is validated by the incoming email server using the public key. Thus, the receiver can easily discern if the email message is legitimate or if the sender’s email address has been spoofed. A mismatch will occur if the content of the email message has been altered on its way as well, so DKIM can also be used to ensure that the sent and the delivered email messages are identical and that nothing has been added or removed. This validation system will increase your email safety, since you can confirm the genuineness of the important email messages that you get and your colleagues can do the exact same thing with the emails that you send them. Depending on the particular mail service provider’s adopted policies, an email message that fails to pass the check may be erased or may reach the recipient’s mailbox with a warning.