SPF, which stands for Sender Policy Framework, is an e-mail safety system, that is employed to validate whether an e-mail message was sent by a certified server. Employing SPF protection for a particular domain will stop the counterfeiting of email addresses made with the domain. In simple words: activating this function 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 mail boxes under the domain. When this record propagates worldwide, it exists on all of the DNS servers that route the Internet traffic. When some email message is sent, the initial DNS server it uses checks whether it comes from an accredited server. In the event it does, it's sent to the destination address, yet when it does not originate from a server part of the SPF record for the domain, it is rejected. Thus nobody will be able to mask an e-mail address to make it appear as if you are e-mailing spam. This technique is also referred to as email spoofing.