NIST should be very proud of the Internet Time Service, which is an important public resource,” says NIST physicist Jeff Sherman, who collected the statistics and co-authored the new report. (The study focused on just two servers because they are local to NIST and easy to access, and they carry 25 percent of the total traffic, a statistically representative sample.)
NIST has operated the Internet Time Service since 1993. The service receives about 16 billion requests per day (as of January 2016). The 20 timeservers are located at 12 sites around the country, including NIST campuses in Gaithersburg, Md., and Boulder, Colo. The servers are linked to the NIST time scale, an ensemble of atomic clocks that maintain the U.S. version of Coordinated Universal Time. The time scale is calibrated by the NIST-F1 and NIST-F2 cesium fountain atomic clocks, the U.S. civilian time standards.
Importantly, the Internet Time Service provides a reliable source of time independent of the satellite-based Global Positioning System. Demand may increase with the growth of the Internet of Things, in which more devices will be connected to the Internet without any direct human intervention.