Authentication
SPF, DKIM, DMARC, transport security, and domain trust.
3 topics in this category.
Sender Policy Framework (SPF)
RequiredPublish a single, bounded SPF policy that authorizes legitimate envelope senders without exceeding the 10-DNS-lookup limit or using overly permissive qualifiers.
DomainKeys Identified Mail (DKIM) Signatures
RequiredCryptographically sign outgoing email messages with DKIM using aligned domains, minimum 2048-bit keys, canonicalization, and regular selector rotation.
Domain-based Message Authentication, Reporting, and Conformance (DMARC)
RequiredEnforce domain-aligned email authentication with a DMARC policy that instructs receivers how to handle unauthenticated mail and generates aggregate feedback reports.