What is TLS-RPT?

TLS-RPT (TLS Reporting) is a DNS record that gives large mail providers an address to send you daily reports about encryption problems when delivering email to your domain - failed secure connections, certificate errors, and attempts to downgrade to an unencrypted session:

• The monitoring half of a pair - MTA-STS sets the rule that mail to your domain must travel over verified encrypted connections, and TLS-RPT tells you when something - misconfiguration or attacker - is breaking that rule.
• Adoption is low - just 4% of Australian small business domains publish a TLS-RPT record^*, consistent with how far down the hardening path it sits: it matters once SPF, DKIM, an enforcing DMARC policy and MTA-STS are all in place.
• The record itself - is one line with a reporting address.

TLS-RPT is free telemetry for a control most businesses haven’t deployed yet - adopt them as a pair, in order.