Network Timing and the 2015 Leap Second

  • Darryl Veitch
  • Kanthaiah Vijayalayan
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 9631)


Using a testbed with reference timestamping, we collected timing data from public Stratum-1 NTP servers during the leap second event of end-June 2015. We found a wide variety of anomalous server-side behaviors, both at the NTP protocol level and in the server clocks themselves, which can last days or even weeks after the event. Out of 176 servers, only 61% had no erroneous behavior related to the leap second event that we could detect.


Leap second NTP Stratum-1 server Network measurement LI bits UTC 



Partially supported by Australian Research Council’s Linkage Projects funding scheme #LP120100073, in partnership with Symmetricom (now Microsemi).


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Copyright information

© Springer International Publishing Switzerland 2016

Authors and Affiliations

  1. 1.Faculty of Engineering and ITUniversity of Technology SydneyUltimoAustralia
  2. 2.Melbourne School of EngineeringUniversity of MelbourneMelbourneAustralia

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