NTP (Network Time Protocol) - Used to synchronize clocks on devices across a network

NTP uses a client-server architecture.

An NTP server listens on udp/123 for time requests from NTP clients. It does not update it's own time

An NTP client and server can be on the same device

NTS (Network Time Security) - Authentication protocol that ensures that the time received from an NTP server is accurate

• Requires an NTS Key Exchange Server on the network

NTS Process with Key Exchange Server

1. Device TLS handshake with KE Server
2. Device requests cookie
3. KE Server responds with cookie
4. Device sends NTP request with cookie to NTP server
5. NTP server responds with accurate time

PTP (Precision Time Protocol) - Hardware base time synchronization

• Provides accuracy down to the nanosecond