What is SPF?

SPF as mentioned under RFC 7208 is an email authentication standard that protects organizations against impersonation. 

SPF, or Sender Policy Framework, is a method that email servers use to determine if an email is legitimate. It's used by companies who send out large amounts of email marketing campaigns, and it helps prevent spoofing and phishing attacks.

It works like this: when you send an email from your company's domain name (e.g., [company name].com),the SPF record for that domain tells other mail servers which IP addresses are authorized to send messages on behalf of your domain. If someone tries to send an email from another IP address, the receiving server can reject it as fake because it doesn't match the SPF record.

What is an SPF Record? 

You can think of SPF like a passport: when you travel abroad, you are required to have one. This is also true for email messages—SPF helps identify which servers are allowed to send messages on behalf of your domain.

The IP addresses of these servers are defined within your SPF record, which can be considered as a directory in your Domain Name System that stores a live list of all authorized sending sources for your domains. 

SPF Record Example 

Given below is an SPF record example:

This record defines a set of hosts as valid senders for all messages sent through the server at 192.168.0.0/16, but it does not specify where those messages will be delivered—they could be delivered locally or they could be delivered by another server on the Internet, depending on how the other servers are configured in the email infrastructure (which we’ll get into later).