paul wrote: [] > Thank you, David. > > In my situation, no GPS is availiable. So can I expect better > performance when GPS is used as reference clock, or when a stratum-1 > NTP server is added to the network?
Local GPS or a local stratum-1 server will make a significant difference. When using the Internet the quality of your connection to the remote server, and the remote server loading are probably more important factors than precisely how that server is synced (i.e. whether it has a local GPS clock). > And, I noticed the offset for Narvik is more stable than that for > Hydra, is it due the PPS feeded to Narvik? But Bacchus is doing good > too without PPS, Why? Hydra is running Windows-7. Because Windows Vista and XP may have a 1KHz clock, the interpolation scheme which is used with XP does not work correctly. So if you like to think of it this way, the Windows-7 system is using purely "native Windows 1KHz" timing, but the XP system is using "interpolated 64Hz" timing, and the guys who wrote and implemented that interpolation did a great job. If Narvik and Hydra had the same OS, I would expect similar performance. Bacchus does currently have a GPS/PPS signal, paralleled off one of the GPS receivers. It runs Windows 2000. It can be a bit of a testbed, so unlike Feenix and Stamsund the GPS/PPS is not guaranteed to be there. Without the GPS/PPS local reference clock, it performs similarly to Narvik. We're into the region where the performance would be improved by keep the PCs, or at least their timing oscillator crystal, at a more constant temperature. Cheers, David _______________________________________________ questions mailing list [email protected] https://lists.ntp.org/mailman/listinfo/questions
