Sender Policy Framework, or SPF, is a verification system, which is used to stop the so-called email spoofing where an email message can be sent from one e-mail, but to seem as being sent from another, ordinarily with the objective to scam the recipient someway. When SPF protection is activated for a domain name, a special record is made for it in the Domain Name System and all the DNS servers globally get it. The record includes all of the e-mail servers that are allowed to send authentic messages from an e-mail address part of the domain. When an email is sent, the first DNS server it goes to verifies the SPF record and when the sending server is permitted, the message is forwarded to the target receiver. When, however, the sending server is not contained in the SPF record for the specified domain, the message won't be submitted and it will be discarded. Whenever you employ this solution, it'll prevent third parties from sending spam e-mails which seem to have been sent from you.