PTP

NTP achieves millisecond-level accuracy, which is sufficient for authentication, logging, and certificate management. Some applications need far more precision: a financial exchange recording trade timestamps needs microsecond accuracy. A broadcast television facility distributing live video needs nanosecond-level synchronization.

PTP achieves this through hardware timestamping — the network card and switch hardware stamp packets at the wire level rather than in software, eliminating the timing jitter introduced by OS scheduling. PTP-aware switches (called boundary clocks or transparent clocks) forward PTP packets while correcting for their own forwarding delays.

The result is sub-microsecond to nanosecond-level clock accuracy across a network.

For most IT environments, PTP is not relevant — NTP is more than adequate. PTP appears in specialized domains: trading infrastructure, broadcast facilities, cellular network backhaul, and industrial automation. If your environment requires PTP, every switch in the path needs to support hardware timestamping, which is a significant infrastructure requirement.