Operated by NIST since 1993, Internet Time Service provides reliable source of time independent of satellite-based GPS. In one month of study alone, just 2 of the 20 NIST servers that supply time information to Internet-connected devices received requests from 316 million unique IP addresses. Located at 12 sites around the country, servers are linked to NIST time scale, an ensemble of atomic clocks that maintain U.S. version of Coordinated Universal Time.