An Acronym for Sender Policy Framework.
A standard defining a DNS record notation to describe which machines are originators of legit Email coming from a certain domain. Its intent is to prevent forging of sender headers in Email, thus hopefully making it more difficult to send Spam.
SPF records are stored in TXT ResourceRecords.
See also:
SPF homepageSPF libraries and patches (adding support for various MTAs)SPF / Exim / Gentoo note by Bob RaseyGentoo bug 58282: Exim needs SPF support4 pages link to SPF:
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