What is Sender Policy Framework (SPF)?
Sender Policy Framework (SPF) is a setup for checking email by determining whether the sender is authorized to use a particular domain. The SPF uses the Domain Name System or the entries to verify a sender against a list of authorized IP addresses.
The SPF is part of a larger effort to protect users who receive email over the Internet. Creating open source SPF resources is part of this step to help protect users from a wide variety of threats associated with using email.
A standard called the Simple Mail Transfer Protocol, a popular protocol for sending messages over IP systems, allows email to be sent from anywhere with a specified source in headers, etc. The SPF is designed to improve email validation by is ensured The sender is authorized.
Without an SPF, an email recipient is vulnerable to something called email spoofing, which allows hackers and other unauthorized parties to use certain types of forged email to trick recipients. Some of these efforts relate to phishing attacks, in which hackers collect personal information about other users through fraudulent email messages.
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