Transport security
MTA-STS tells participating senders to require trusted TLS for delivery to your MX hosts. TLS-RPT provides aggregate evidence about successful sessions and transport failures. DMARC123 generates the DNS setup, hosts policy files, validates public behavior, and organizes the reports.
Policy hosting
A managed domain may publish an mta-sts CNAME to dmarc123.com so DMARC123 can serve the policy. Customers may instead route that hostname to their own server. In either model, the policy must remain available at /.well-known/mta-sts.txt with a valid certificate for the managed-domain hostname.
DNS validation
DMARC123 checks the MTA-STS hostname route, policy TXT record, TLS-RPT TXT record, public policy URL, and policy content. The domain header reflects the current validation result rather than a separate workflow status.
TLS reporting
Successful-session totals are displayed as aggregate evidence. Receiving MX, receiving IP, sending MTA IP, result type, and failed-session count appear only when the report actually contains failure-detail objects.
Operational clarity
A success-only TLS policy displays a success summary instead of a fabricated zero-count detail row. When a sender reports failures without detail records, DMARC123 states that limitation explicitly.
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Existing users can sign in. Organizations evaluating DMARC123 can contact PM Technologies to discuss account access and deployment.
