SPF, which is an acronym for Sender Policy Framework, is an email protection system, which is is intended to confirm whether an e-mail message is sent by an authorized server. Employing SPF protection for a given domain name will stop the counterfeiting of email addresses made with the domain. In simple words: enabling this attribute for a domain creates a specific record in the Domain Name System (DNS) which includes the IP addresses of the servers which are permitted to send emails from mailboxes using the domain. The moment this record propagates worldwide, it will exist on all DNS servers that direct the Internet traffic. When some email message is sent, the initial DNS server it goes through verifies if it comes from an accredited server. When it does, it is forwarded to the destination address, however when it doesn't originate from a server part of the SPF record for the domain, it is rejected. In this way nobody will mask an email address to make it look as if you're e-mailing spam. This approach is also referred to as email spoofing.