Sender Policy Framework, or SPF, is a validation system, which is employed to stop the so-called email spoofing where an e-mail message is sent from one e-mail, but to look as being sent from a different one, frequently with the idea to scam the recipient for some reason. If SPF protection is activated for a domain, a special record is generated for it in the Domain Name System and all of the DNS servers worldwide have it. The record features all email servers that are allowed to send legitimate messages from an email address part of the domain. When a message is sent, the very first DNS server it encounters verifies the SPF record and if the sending server is authorized, the message is sent to the targeted destination. When, however, the sending server is not present in the SPF record for the given domain, the message won't be forwarded and it will be removed. When you employ this solution, it will prevent third parties from sending spam messages which look as if they have been sent from you.