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Re: [Ntp] Antw: [EXT] Re: Timescales

FUSTE Emmanuel <emmanuel.fuste@thalesgroup.com> Wed, 09 December 2020 14:07 UTC

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From: FUSTE Emmanuel <emmanuel.fuste@thalesgroup.com>
To: "ntp@ietf.org" <ntp@ietf.org>
Thread-Topic: [Ntp] Antw: [EXT] Re: Timescales
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Date: Wed, 09 Dec 2020 14:07:28 +0000
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Subject: Re: [Ntp] Antw: [EXT] Re: Timescales
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Le 09/12/2020 à 14:46, Miroslav Lichvar a écrit :
> On Wed, Dec 09, 2020 at 02:29:32PM +0100, Ulrich Windl wrote:
>> However you could see the leap indication flag also as "leap confirmation"
>> flag (actually there will be a leap event). With only DCF-77 clocks this could
>> be a problem. As said earlier, it would be best if NTP could reliably transfer
>> the leapsecond table, or at least the relevant part of it to make clients know
>> in advance that and when a leap event is scheduled.
> There is the tzdist (RFC7808) protocol designed for that.
>
> NTP could distribute a leap-second table (it already did it with
> Autokey, right?), but isn't NTP about distributing current time,
> rather than reconstructing time in the past or future?
>
"Current" is a referential problem. As soon as you distribute/tackle 
different time scale which one is "current" ?
You will more or less  inevitably start to need to reconstruct time in 
the past or future.

Emmanuel.

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