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

Harlan Stenn <stenn@nwtime.org> Thu, 16 April 2020 21:13 UTC

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From: Harlan Stenn <stenn@nwtime.org>
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Date: Thu, 16 Apr 2020 14:12:54 -0700
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Subject: Re: [Ntp] The bump, or why NTP v5 must specify impulse response
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On 4/16/2020 6:55 AM, Kurt Roeckx wrote:
> 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?

Srsly?  No.

What is your definition of "improved"?

Does it cast the wide net that the current definitions and
specifications cover?

> 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?

At least you're thinking about this.

There are cases with regulatory requirements here.

There are liability risks.

Then again, the WG may decide to punt all of this for V5.

Similar to what POSIX did around leap seconds.

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

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