DomainKeys Identified Mail (DKIM) is a validation system used to prove that an email has been sent by an authorized server or person. An e-signature is attached to the header of the email message by using a private encryption key. When the message is received, a public key that is available in the global Domain Name System is used to check who actually sent it and if the content has been modified in some way. The main task of DomainKeys Identified Mail is to obstruct the widely spread scam and spam messages, as it makes it impossible to fake an email address. If an email message is sent from an address claiming to belong to your bank or financial institution, for instance, but the signature does not correspond, you will either not get the email at all, or you will get it with a notification that most probably it’s not a genuine one. It depends on mail service providers what exactly will happen with an email that fails the signature examination. DKIM will also give you an added security layer when you communicate with your business partners, for example, as they can see for themselves that all the emails that you send are legitimate and haven’t been tampered with on their way.
