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Re: [Ntp] Timescales

Steve Allen <sla@ucolick.org> Thu, 10 December 2020 01:28 UTC

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Date: Wed, 09 Dec 2020 17:28:00 -0800
From: Steve Allen <sla@ucolick.org>
To: NTP WG <ntp@ietf.org>
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Subject: Re: [Ntp] Timescales
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On Wed 2020-12-09T17:33:08-0700 Philip Prindeville hath writ:
> It seems to me that time advances, only, and at a fairly constant rate [...]
>
> It simply goes “tick tock tick tock”… and that’s all it does.

Time does that and clocks do not.

In the arena of precise time a few basic principles that do not exist
in POSIX time are

All sources of time disagree; all clocks are wrong.
Political/legal/bureaucratic concerns of agencies funding maintenance
and distribution of time sometimes overrule technical concerns.
Systems wanting precise time need a plan for dealing with all that.

--
Steve Allen                    <sla@ucolick.org>              WGS-84 (GPS)
UCO/Lick Observatory--ISB 260  Natural Sciences II, Room 165  Lat  +36.99855
1156 High Street               Voice: +1 831 459 3046         Lng -122.06015
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