SPF, which abbreviates Sender Policy Framework, is an authentication system that aims at blocking the so-called email counterfeiting. Basically, this indicates sending a message from one email and making it look like it’s sent from another one with the purpose to scam in some way the person receiving it. When the SPF protection is activated for a domain name, a record which has all of the mail servers authorized to email messages with addresses under the domain is created. The record is kept on all the DNS servers that direct the web traffic worldwide, therefore they all will recognize whether an e-mail message originates from a trustworthy server or not. The check is performed at the first server where the email goes through and in the first case the e-mail message is forwarded, and in the second it's discarded and it never gets to the intended recipient. Employing SPF records for your domain names will stop any unauthorized people from making use of your email addresses for harmful objectives.