SPF, which is short for Sender Policy Framework, is an email protection system, which is employed to confirm whether an e-mail message was sent by a certified server. Employing SPF protection for a domain will stop the forging of email addresses made with the domain. In layman's terms: activating this feature for a domain makes a specific record in the Domain Name System (DNS) which contains the IP of the servers that are allowed to send e-mail messages from mailboxes under the domain. Once this record propagates globally, it exists on all the DNS servers that route the Internet traffic. When an e-mail message is sent, the initial DNS server it uses tests whether it originates from an accredited server. In the event it does, it's forwarded to the destination address, yet if it does not come from a server part of the SPF record for the domain, it is discarded. In this way nobody will mask an e-mail address and make it look as if you are distributing spam messages. This approach is also identified as email spoofing.