Sender Policy Framework, or SPF, is a validation system, which is designed to prevent the so-called e-mail spoofing where an e-mail message can be sent from one address, but to look as being sent from another, generally with the purpose to fraud the recipient someway. If SPF protection is enabled for a domain name, a specific record is made for it in the Domain Name System and all of the DNS servers around the world receive it. The record includes all of the email servers that are permitted to send valid messages from an email address within the domain. When an email is sent, the very first DNS server it goes to verifies the SPF record and in case its sending server is permitted, the message is sent to the targeted destination. When, however, the sending server is not present in the SPF record for the specified domain, the e-mail message won't be forwarded and it'll be removed. When you employ this solution, it will stop third parties from sending spam messages which seem to have been sent from you.