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

Martin Burnicki <martin.burnicki@meinberg.de> Wed, 09 December 2020 22:53 UTC

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From: Martin Burnicki <martin.burnicki@meinberg.de>
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Subject: Re: [Ntp] Antw: [EXT] Re: Timescales
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Miroslav Lichvar wrote:
> 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?

As I said earlier, IMO the current TAI offset would be sufficient.

BTW, do you know Poul-Henning Kamp's Proposal to distribute leap second
warning and the current TAI offset via DNS? See:
http://phk.freebsd.dk/time/20151122/


Martin
-- 
Martin Burnicki

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