SPF
Definition
SPF (Sender Policy Framework) is an email authentication protocol that allows domain owners to specify which mail servers are authorized to send emails on their behalf.
Examples
- A company publishes an SPF record in its DNS to specify that only its mail servers and a trusted marketing platform can send emails from its domain.
- An email from an unauthorized IP address fails SPF checks and is flagged as potentially fraudulent by the recipient's mail server.
Overview
SPF (Sender Policy Framework) is a DNS-based email authentication protocol that helps prevent email spoofing and unauthorized use of a domain in email headers. It allows the owner of a domain to specify which IP addresses or servers are permitted to send email on behalf of that domain.
By checking the SPF record of the sending domain, receiving mail servers can verify whether the message came from an authorized source. If the sender is not listed in the domain’s SPF record, the message may be rejected, quarantined, or marked as suspicious, depending on the recipient’s email security policy.
SPF plays a critical role in defending against phishing attacks, spam, and business email compromise by making it harder for attackers to impersonate trusted domains.
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