DKIM, which is an abbreviation for DomainKeys Identified Mail, is an email authentication system, which blocks email headers from being forged and email content from being manipulated. This is achieved by adding an e-signature to each and every email sent from an email address under a specific domain name. The signature is issued on the basis of a private encryption key that is available on the SMTP server and it can be verified by using a public key, which is available in the global DNS database. Thus, any email message with edited content or a spoofed sender can be recognized by email service providers. This method will strengthen your online security immensely and you’ll be sure that any e-mail sent from a business partner, a banking institution, etc., is a genuine one. When you send out messages, the recipient will also know for sure that you are indeed the one who has sent them. Any email message that appears to be fake may either be tagged as such or may never show up in the recipient’s mailbox, based on how the particular provider has chosen to cope with such emails.