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

Harlan Stenn <stenn@nwtime.org> Tue, 06 September 2022 05:11 UTC

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From: Harlan Stenn <stenn@nwtime.org>
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Subject: Re: [Ntp] Antw: Re: Antw: [EXT] NTPv5 Loop Detection without Stratum
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Please indulge me.

There seems to be significant concern about some number of servers 
getting in to a loop.

Why?

What are the conditions under which this would happen?

What are the various end results of the condition(s) in which this happens?

Is there (something like) a "root distance" involved?

If so, at what point does a sufficiently large root distance affect each 
member of the loop?

Has any consideration been given to NTPv4's orphan mode, or even 
fallback to the local clock at a suitable stratum?

How many more time sources would be needed to prevent a loop?  How does 
the availability of 1 more time source affect this?  2 more?  3?

-- 
Harlan Stenn <stenn@nwtime.org>
http://networktimefoundation.org - be a member!

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