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Re: [Ntp] The bump, or why NTP v5 must specify impulse response

Kurt Roeckx <kurt@roeckx.be> Thu, 16 April 2020 13:55 UTC

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Date: Thu, 16 Apr 2020 15:55:47 +0200
From: Kurt Roeckx <kurt@roeckx.be>
To: Harlan Stenn <stenn@nwtime.org>
Cc: Tony Finch <dot@dotat.at>, NTP WG <ntp@ietf.org>, "Salz, Rich" <rsalz=40akamai.com@dmarc.ietf.org>, Watson Ladd <watsonbladd@gmail.com>, Daniel Franke <dfoxfranke@gmail.com>, Doug Arnold <doug.arnold@meinberg-usa.com>, Dieter Sibold <dsibold.ietf@gmail.com>
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Subject: Re: [Ntp] The bump, or why NTP v5 must specify impulse response
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On Thu, Apr 16, 2020 at 06:43:00AM -0700, Harlan Stenn wrote:
> 
> >From the NTP Project's POV, chronyd is *not* a conforming NTP
> implementation, as it uses different algorithms and does not honor the
> behavioral characteristics of the application of impulse changes.

Does that mean you're saying that the algorithms can't be
improved?

Does that mean that if you support NTPv4 and NTPv5, and NTPv5 has a
different algorithm, and you talk to something that does NTPv4,
you should have a complete emulation of what an NTPv4 server
should have done, including serving a different time because
the impulse response is different?


Kurt

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