Network Timing and the 2015 Leap Second
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.
KeywordsLeap 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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