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Re: [Ntp] [EXT] Re: The bump, or why NTP v5 must specify impulse response

Warner Losh <imp@bsdimp.com> Tue, 14 April 2020 21:10 UTC

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From: Warner Losh <imp@bsdimp.com>
Date: Tue, 14 Apr 2020 15:10:43 -0600
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To: "Salz, Rich" <rsalz=40akamai.com@dmarc.ietf.org>
Cc: Ulrich Windl <Ulrich.Windl@rz.uni-regensburg.de>, Miroslav Lichvar <mlichvar@redhat.com>, "ntp@ietf.org" <ntp@ietf.org>
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Subject: Re: [Ntp] [EXT] Re: The bump, or why NTP v5 must specify impulse response
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On Tue, Apr 14, 2020 at 3:06 PM Salz, Rich <rsalz=
40akamai.com@dmarc.ietf.org> wrote:

>
> >    Yes, I also realized that our GPS-based startum-1 server basically
>     measures room temperature when looking at the frequency correction.
>
> HA!
>
> But at least you don't have quantum effects if you change floors, right? :)
>

Only if you fly in planes or are moving. The Sagnac Effect is quite real
even at low speeds in a spinning environment.

Working at Timing Solutions years ago, we had to rope off an area around a
test system. You could see when a certain manager would lumber through the
lab in the data, which spoiled the calibration that was being done and it
had to start over... :)

But neither of these are likely effects large enough to matter to ntp.

Warner

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