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Usage analysis of a national internet time service



Jeffrey A. Sherman, Judah Levine


The Internet Time Service (ITS) at the National Institute of Standards and Technology (NIST) currently receives over 12 billion time requests per day. ITS servers derive their system time from the NIST atomic-referenced timescale and distribute it freely to the public. Here we explore detailed ITS usage patterns discovered by analysis of inbound network traffic. For example, over a period of four weeks, just two of the approximately twenty ITS servers received requests from 316 million unique Internet Protocol (IPv4) addresses, which is at least 8.5% of the entire Internet. We offer recommendations for providers and consumers of network time services.
Journal of Research (NIST JRES) -


internet time service, network time protocol (NTP), time transfer


Sherman, J. and Levine, J. (2016), Usage analysis of a national internet time service, Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD (Accessed April 23, 2024)
Created March 8, 2016, Updated November 14, 2018