Re: [Ntp] [EXT] Hard NO: Re: WGLC - draft-ietf-ntp-ntpv5-requirements

Hal Murray <halmurray@sonic.net> Tue, 19 December 2023 09:08 UTC

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To: "Windl, Ulrich" <u.windl@ukr.de>
cc: "ntp@ietf.org" <ntp@ietf.org>, Hal Murray <halmurray@sonic.net>
From: Hal Murray <halmurray@sonic.net>
In-Reply-To: Message from "Windl, Ulrich" <u.windl@ukr.de> of "Tue, 19 Dec 2023 08:30:26 +0000." <68d0192572af4a0e9374f372b0221752@ukr.de>
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Subject: Re: [Ntp] [EXT] Hard NO: Re: WGLC - draft-ietf-ntp-ntpv5-requirements
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u.windl@ukr.de said:
> I wonder about the "defined response to a "time impulse"":

I think the idea behind that is that PLLs in series are (much) more 
complicated than single PLLs.  If each individual PLL is stable, the chain may 
be unstable.

I'm not enough of a PLL wizard to provide a good explanation.

This becomes a problem when people notice that it takes a long time for NTP to 
settle so they dig around and find the time constand and make it converge 
faster.  What works on their system is less likely to work on a deeper stratum 
or may not even be stable on their current system -- just waiting for the 
right input signal to come along.


-- 
These are my opinions.  I hate spam.