NTPd does. However, in order the eliminate it, it assumes the RTT is symmetric, that is half is on the journey to the remote, half on the journey back. Asymmetric links do lead to systemic error in NTP.
(It assumes symmetry because there isn't any way to measure the asymmetry without first having time sync, and obvious catch-22. If you need better than 10ms accuracy, you'll need a GPS, etc.)
(It assumes symmetry because there isn't any way to measure the asymmetry without first having time sync, and obvious catch-22. If you need better than 10ms accuracy, you'll need a GPS, etc.)