QuestionHow Was SecureSync and NetClock 9400 Tested for Handling the December 31 2016 Leap Second?
AnswerTesting on SecureSync and NetClock 9400 products confirms proper handling of the leap second event at UTC midnight on December 31, 2016. Our testing consisted of combinations of application software, GPS receiver and its firmware and timing protocol as shown below.
- 5.5.0 (pending December release)
- 5.4.1 (see note below)
- Trimble Res-T v1.14
- Trimble Res-T v 1.17
- Trimble Res-T v 1.20
- Trimble Res SMT GG v1.9 (UTC and GPS)
- U-Blox v2.3
- All SAASM receivers
- IRIG timecodes
- ASCII timecodes
Recommendations and Notes
Our recommendation is to upgrade application software to the latest version in advance of the leap second event.
In the nominal case of using GPS as a reference, no user intervention is required. However, there is a specific condition that may require user intervention if the unit is not running the latest application software version. For those units running version 5.4.1 and the primary reference is another NTP server (stratum-2 operation) the leap second will not be resolved in any generated signals. There would be a 1 second error in these signals for a few minutes until the timing engine resolves the discontinuity in timestamps from the NTP server. The workaround is to login to the device and manually configure the leap second indicator before the leap second event, or upgrade to the latest version of application software.