SPF, which is an acronym for Sender Policy Framework, is an email security system, which is employed to verify whether an e-mail message is sent by a certified server. Employing SPF protection for a domain will prevent the faking of email addresses made with the domain. In simple words: activating this attribute for a domain name generates a special record in the Domain Name System (DNS) that contains the IP addresses of the servers that are allowed to send email messages from mailboxes under the domain. As soon as this record propagates globally, it will exist on all DNS servers that route the Internet traffic. Whenever an email message is sent, the first DNS server it goes through tests whether it originates from an official server. When it does, it is sent to the destination address, yet if it doesn't come from a server part of the SPF record for the domain, it's rejected. Thus nobody will mask an e-mail address and make it appear as if you're e-mailing spam messages. This method is also identified as email spoofing.