[ntp:questions] NTP vs RADclock?

skillzero at gmail.com skillzero at gmail.com
Thu Jun 7 06:23:04 UTC 2012

On Jun 6, 10:45 pm, David Woolley <da... at ex.djwhome.demon.invalid>
> skillz... at gmail.com wrote:
> > 2. Separate offset sync from rate sync. What I wasn't sure about is
> > why the rate sync would be so much more stable than offset sync since
> > they seem to both come from the same packet exchanges. Is the
> > advantage that the rate sync is smoothed over time whereas the offset
> > sync isn't?
> I seem to remember that NTPV3 had a fast loop for phase and a slower
> loop for frequency.

Do you mean NTP using a PLL for poll intervals below the Allan
intercept (~2000 seconds) and an FLL for poll intervals above it? I'm
aware of that aspect of it, but if I understand it correctly, that was
still used for both offset and rate synchronization.

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