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DMARC ASPF -
The "aspf" tag stands for "Alignment Mode for SPF." It specifies how the SPF authentication results should be aligned with the email's From domain, and can have two values:
- "r": Relaxed alignment. SPF authentication results must only partially match the email's "Return-Path" (or "MAIL FROM") address and the email's From domain.
- "s": Strict alignment. Requires a strict alignment between the domain specified in the "Return-Path" (or "MAIL FROM") address and the email's From domain.
When these tags are combined within a DMARC record, it allows domain owners to request that recipient mail servers handle email originating from their domain in a specific way.
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