NTS: Authenticated Time at Meta
Summary
This Meta Engineering post explains Network Time Security (NTS, RFC 8915) and how Meta is deploying authenticated time via nts.meta.com. It covers the motivation for authenticating time, the stateless cookie design, the two-phase NTS handshake, and how clients can adopt NTS, while noting adoption gaps on mobile platforms and the broader security implications of secure time as the root for certificates and tokens.