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

Dieter Sibold <dsibold.ietf@gmail.com> Thu, 16 April 2020 17:28 UTC

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From: Dieter Sibold <dsibold.ietf@gmail.com>
To: Harlan Stenn <stenn@nwtime.org>
Cc: "Salz, Rich" <rsalz=40akamai.com@dmarc.ietf.org>, Doug Arnold <doug.arnold@meinberg-usa.com>, Watson Ladd <watsonbladd@gmail.com>, NTP WG <ntp@ietf.org>, Daniel Franke <dfoxfranke@gmail.com>
Date: Thu, 16 Apr 2020 19:27:29 +0200
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Subject: Re: [Ntp] The bump, or why NTP v5 must specify impulse response
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The problem with this combination is that we currently have no 
implementation that conforms to RFC5905 completely.
There are different use cases for potential clients. Some of them are 
not well served with the current algorithm other are. A modular approach 
would allow both: to apply an algorithm most suitable to the application 
and to be compliant with the protocol spec.

Dieter


On 16 Apr 2020, at 11:58, Harlan Stenn wrote:

> On 4/15/2020 6:38 AM, Salz, Rich wrote:
>>>    We had the same discussion at the transition from ntpv3 to ntpv4.
>>>    If you do this, please do not call it NTP.
>>
>> Can you explain why 3->4 could still be called NTP but 4->5 should 
>> not?
>
> You didn't quote enough context.
>
> NTP is a combination of two parts:
>
> - the protocol/packet structure
> - algorithmic and response behavior
>
> If you are only specifying the protocol in this new thing then it is
> dangerous/misleading/irresponsible to call this v5 document "NTP".
>
> It is only slightly less dangerous/misleading/irresponsible to call it
> "NTPv5 Protocol", regardless of whether or not there is also an "NTPv5
> Algorithms and Response Behavior".
>
> -- 
> Harlan Stenn <stenn@nwtime.org>
> http://networktimefoundation.org - be a member!

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