Email SPF (Sender Policy Framework) is an email authentication protocol that helps prevent email spoofing and phishing by verifying that the sender of an email message is authorized to send messages on behalf of the domain in the message’s “From” field.
In other words, SPF allows the recipient’s email server to check that the sender’s IP address is allowed to send email on behalf of the domain in the “From” field. If the IP address is not authorized, the email can be rejected or marked as spam.
To set up SPF for a domain, the domain owner creates a DNS TXT record that lists the authorized IP addresses or domains that are allowed to send email on behalf of that domain. When an email is received, the recipient’s email server checks the SPF record to see if the sending IP address is authorized. If the IP address is authorized, the email is delivered as normal. If it’s not authorized, the email may be rejected or marked as spam.
SPF is one of several email authentication protocols, including DKIM (DomainKeys Identified Mail) and DMARC (Domain-based Message Authentication, Reporting, and Conformance), that are designed to improve email security and reduce email fraud.