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Improvements to the NIST Network Time Protocol Servers



Judah Levine


The National Institute of Standards and Technology operates 22 network time servers at various locations. These servers respond to requests for time in a number of different formats, and provide time stamps that are directly traceable to the NIST atomic clock ensemble in Boulder. The link between the servers at locations outside of the NIST Boulder Laboratories and the atomic clock ensemble is provided by the ACTS system, which has a direct connection to the clock ensemble and which transmits time information over dial-up telephone lines using a two-way protocol to measure the transmission delay. I will discuss improvements to the ACTS servers and to the time servers themselves. These improvements have resulted in almost an order of magnitude improvement in the performance of the system.


ACTS, Internet Time, Network Time Protocol, NTP


Levine, J. (2008), Improvements to the NIST Network Time Protocol Servers, Metrologia (Accessed July 21, 2024)


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Created December 5, 2008, Updated February 17, 2017