Where on Earth Are the Best-50 Time Servers?

  • Yi CaoEmail author
  • Darryl Veitch
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 11419)


We present a list of the Best-50 public IPv4 time servers by mining a high-resolution dataset of Stratum-1 servers for Availability, Stratum Constancy, Leap Performance, and Clock Error, broken down by continent. We find that a server with ideal leap performance, high availability, and low stratum variation is often clock error-free, but this is no guarantee. We discuss the relevance and lifetime of our findings, the scalability of our approach, and implications for load balancing and server ranking.


Leap second NTP Stratum-1 server Network measurement LI bits UTC Load balancing Clock synchronization 



Partially supported by Australian Research Council’s Discovery Projects funding scheme #DP170100451.


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.School of Electrical and Data EngineeringUniversity of Technology SydneySydneyAustralia

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