What is Sender Policy Framework (SPF)?

Sender policy framework (SPF) is an email authentication method that identifies mail servers allowed to send emails for a given domain.

Because of SPF, Internet service providers can identify scammers, phishing, or spoofers when they are trying to send malicious emails from a domain that belongs to a company or a brand.

Firstly, SPF establishes a policy framework (SPF record) that profiles which email servers are authorized to send emails from that domain.

When an inbound server receives an email, it references the rules for the bounce domain in the Domain Name System (DNS). Next, it compares the IP address of the incoming email to the authorized addresses defined in the SPF record.

The receiving server uses SPF record rules to determine if the incoming email will be rejected, accepted, or flagged.

SPF record check or SPF validator is a tool that determines whether an SPF record is valid. It looks up the record, displays found records and tests it to find any issues that could create problems when delivering emails.

An SPF record provides an additional layer of security since it allows domain owners to create a list of approved inbound domains to minimize the risk of phishing or scamming and helps other servers verify your domain’s legitimacy.

SPF, DKIM, and DMARC are all protocols that enhance email security.

SPF alone isn’t enough to recognize spoofed messages since the sender’s address (From field) can be pirated. They all work together but differently.

DKIM cryptographically verifies that the From field (sender’s address) and message haven’t been changed in transit.

DMARC checks that the domain in SPF and DKIM check matches the sender’s domain in the From field. If the message fails both SPF and DKIM, it specifies how service providers should deliver it – accept, reject, or mark it as spam.