SPF
Sender Policy Framework
An email standard that lists which servers may send for a domain.
Sender Policy Framework is an email authentication method that publishes, in DNS, the list of mail servers authorized to send for a domain, letting receivers reject mail from unauthorized sources. It helps counter spoofing and phishing that forge the envelope sender. SPF alone breaks when mail is forwarded and does not check the visible From header. It works best combined with DKIM, which signs messages, and DMARC, which sets policy and alignment across both and enables reporting.
Sender Policy Framework: lists which mail servers may send for your domain.
Looking SPF up is step one. Getting tested on it is step two.
A free account opens all 4 Domain 1 objectives, 271 exam-style questions with a lesson and a lab on each, a placement check that skips what you already know, and a dated plan. No card.
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