SPF, which is short for Sender Policy Framework, is an e-mail protection system, which is designed to verify whether an e-mail message was sent by a certified server. Employing SPF protection for a particular domain name will stop the faking of email addresses generated with the domain. In simple words: activating this feature for a domain name makes a special record in the Domain Name System (DNS) that contains the IP of the servers that are allowed to send email messages from mail boxes under the domain. Once this record propagates worldwide, it will exist on all of the DNS servers that route the Internet traffic. Any time some e-mail message is sent, the first DNS server it goes through tests whether it originates from an accredited server. In the event it does, it is sent to the destination address, yet when it doesn't originate from a server indexed in the SPF record for the particular domain, it's discarded. In this way nobody will be able to mask an email address then make it look as if you are sending spam. This technique is also identified as email spoofing.