SPF, which is short for Sender Policy Framework, is an e-mail protection system, that is is intended to validate whether an e-mail message was sent by an authorized server. Using SPF protection for a particular domain will prevent the counterfeiting of emails made with the domain. In layman's terms: enabling this feature for a domain name makes a special record in the Domain Name System (DNS) containing the IP addresses of the servers which are permitted to send email messages from mail boxes under the domain. When this record propagates worldwide, it exists on all DNS servers that direct the Internet traffic. Any time a new email message is sent, the first DNS server it goes through tests if it originates from an authorized server. If it does, it is sent to the destination address, yet when it does not originate from a server indexed in the SPF record for the domain, it is discarded. Thus nobody can mask an email address to make it look as if you're distributing spam messages. This approach is also identified as email spoofing.