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[Ntp] Antw: [EXT] Re: Temperature Compensation for NTP?

Ulrich Windl <Ulrich.Windl@rz.uni-regensburg.de> Tue, 08 December 2020 15:06 UTC

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Date: Tue, 08 Dec 2020 16:06:46 +0100
From: Ulrich Windl <Ulrich.Windl@rz.uni-regensburg.de>
To: "ntp@ietf.org" <ntp@ietf.org>, mlichvar@redhat.com
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Subject: [Ntp] Antw: [EXT] Re: Temperature Compensation for NTP?
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>>> Miroslav Lichvar <mlichvar@redhat.com> schrieb am 08.12.2020 um 11:00 in
Nachricht <20201208100015.GU2352378@localhost>:
> On Tue, Dec 08, 2020 at 10:35:45AM +0100, Ulrich Windl wrote:
>> Hi!
>> 
>> The avarage computer oscillator is mainly controlled by temperature. Up to

> now NTP does not have a computational model to consider the temperature 
> nearby the oscillator, while most modern systems have some temperature 
> sensor(s).
> 
> I don't see how this is related to NTP. Is the current specification
> preventing servers or clients from implementing a software temperature
> compensation?

If the protocol standard does not specify a clock model, I'm fine. However
(e.g.) the increase of dispersion (which is way too large IMHO) will mostly
depend on the environental stability. So to get that value right or atr least
close, one would have to take temperature effect into account.
Or alternatively: Quickly explain how the increase of dispersion was
determined ;-)

Regars,
Ulrich

> 
> ‑‑ 
> Miroslav Lichvar

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