Re: [Ntp] CLOCK_TAI (was NTPv5: big picture)

Kurt Roeckx <kurt@roeckx.be> Tue, 05 January 2021 16:33 UTC

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Date: Tue, 05 Jan 2021 17:32:33 +0100
From: Kurt Roeckx <kurt@roeckx.be>
To: Magnus Danielson <magnus@rubidium.se>
Cc: Miroslav Lichvar <mlichvar@redhat.com>, ntp@ietf.org
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Subject: Re: [Ntp] CLOCK_TAI (was NTPv5: big picture)
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On Tue, Jan 05, 2021 at 04:51:13PM +0100, Magnus Danielson wrote:
> 
> Actually, here lies a problem. There seems to be fairly wide agreement
> that we want the core time-stamping to use a TAI-like form of time. This
> means, it keeps ticking, behaves like a well-functioned linear ramp.
> That makes any processing of it easy and so does all encoding.
> 
> UTC fails to be such a ramp in many encodings. When the leapsecond is
> inserted in 23:59:60, that becomes an encoding challenge for all the
> formats I know.

So you can opt to change the encoding of UTC, and use a
combination of days and seconds in that day.


Kurt