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Sender Policy Framework
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Application Layer — Email
Protocol Overview
Full Name
Sender Policy Framework
Abbreviation
SPF
OSI Layer
Application Layer
Category
Email
RFC
RFC 7208
About SPF
Email authentication protocol that specifies which mail servers are authorized to send email for a domain via DNS TXT records.
Application Layer
Email
Standards Reference
SPF is defined in RFC 7208, published by the Internet Engineering Task Force (IETF). RFCs are the official standards documents for internet protocols and are freely available for public review.