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[Ntp] Antw: Re: Antw: Re: Antw: [EXT] NTPv5 Loop Detection without Stratum

Ulrich Windl <Ulrich.Windl@rz.uni-regensburg.de> Wed, 31 August 2022 06:22 UTC

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Date: Wed, 31 Aug 2022 08:21:59 +0200
From: Ulrich Windl <Ulrich.Windl@rz.uni-regensburg.de>
To: halmurray@sonic.net
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Subject: [Ntp] Antw: Re: Antw: Re: Antw: [EXT] NTPv5 Loop Detection without Stratum
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>>> Hal Murray <halmurray@sonic.net> schrieb am 30.08.2022 um 22:11 in
Nachricht
<20220830201114.8AEE728C1D8@107-137-68-211.lightspeed.sntcca.sbcglobal.net>:

> Ulrich.Windl@rz.uni‑regensburg.de said:
>> But if the Reference ID for all GPS clocks would be "GPS ", wouldn't he
new
>> "loop avoidance" algorithm consider all those to be the same source, thus
a
>> loop? So we could not have redundant GPS sources any more??? 
> 
> That (or a variation) could be a feature rather than a bug.  Consider the 
> case 
> where some of the GPS receivers have a bug.  The obvious example is 1024 
> week 
> rollover.

Unfortunately about 90% (I guess) of all time servers use GPS. Fortunately a
time jump of one or several weeks is rather easy to discover, specifically when
jumping back.

> 
> ‑‑ 
> These are my opinions.  I hate spam.
> 
> 
> 
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