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

Danny Mayer <mayer@pdmconsulting.net> Mon, 05 September 2022 19:51 UTC

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Date: Mon, 05 Sep 2022 15:50:50 -0400
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To: Ulrich Windl <Ulrich.Windl@rz.uni-regensburg.de>, halmurray@sonic.net
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From: Danny Mayer <mayer@pdmconsulting.net>
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Subject: Re: [Ntp] Antw: Re: Antw: Re: Antw: [EXT] NTPv5 Loop Detection without Stratum
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On 8/31/22 2:21 AM, Ulrich Windl wrote:
>> 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.
>
NTP (at least the reference implementation as I cannot say what the 
others do) will refuse to move back or forward that much and would 
consider the timestamp invalid.

Danny

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