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RFC 7208 / MECHANISM GUIDE

Mechanisms and qualifiers

03

Policy terms are evaluated in order until a mechanism matches.

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DIAGRAM§ 4.6 ↗
RFC 7208 · § 4.6EXAMPLE
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Mechanisms and qualifiersPolicy terms are evaluated in order until a mechanism matches.Mechanisms and qualifiersv=spf1 ip4:192.0.2.10 -allOtherwise reach -all → fail
03
Reach -all otherwise

An unmatched sender reaches the illustrated fail result.

Protocol participantThreat or exceptionProtocol controlSimplified drawings · precise section references
KEY POINT

ip4 and ip6 test addresses; include invokes another domain’s policy under its defined rules.

  • ip4 and ip6 test addresses; include invokes another domain’s policy under its defined rules.
  • Qualifiers select pass, fail, softfail, or neutral when a term matches.
  • all always matches and commonly supplies a final result.
DETAILS

Examples are illustrative. Consult the linked RFC and its errata for implementation details.

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Privacy
All chapters in this RFC
  1. Which identity SPF checks
  2. Publish and find the record
  3. Mechanisms and qualifiers
  4. DNS work and errors
  5. Forwarding and result meaning
RFC 9700 / CHAPTERS

Chapters

For full details, tables, algorithms, and exceptions, read the original RFC.

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