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[Ntp] Antw: [EXT] Re: NTPv5 Loop Detection without Stratum ‑ Why do we want this?

Ulrich Windl <Ulrich.Windl@rz.uni-regensburg.de> Wed, 21 September 2022 05:53 UTC

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Date: Wed, 21 Sep 2022 07:53:43 +0200
From: Ulrich Windl <Ulrich.Windl@rz.uni-regensburg.de>
To: mayer@pdmconsulting.net, mlichvar@redhat.com
Cc: heiko.gerstung=40meinberg.de@dmarc.ietf.org, kristof.teichel=40ptb.de@dmarc.ietf.org, "ntp@ietf.org" <ntp@ietf.org>
References: <DA1F1664-8A84-4197-844A-CA7E8DAA36B8@meinberg.de> <OF43150191.DABAA331-ONC12588B5.00362DC0-C12588B5.003861AF@ptb.de> <YxckOm2+TD3tTPN4@localhost> <7d7f0656-2fd2-b781-4913-526a4be8cb62@pdmconsulting.net> <Yxg4Cba58hI/aPKw@localhost> <aba44bbc-2204-735e-daff-a29a59dac9da@pdmconsulting.net> <YxmKlSVTzOQah/nc@localhost> <10b1b402-9386-4fb3-4297-38d31bdc5c96@pdmconsulting.net> <Yx8I6sTGKTLKJr8c@localhost> <796c33e6-02dc-0665-c8a2-a143f9100bdd@pdmconsulting.net> <Yygb4pt5JdyIszWU@localhost> <23f26126-c39e-16ea-d862-c8ac706e37d5@pdmconsulting.net>
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Subject: [Ntp] Antw: [EXT] Re: NTPv5 Loop Detection without Stratum ‑ Why do we want this?
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>>> Danny Mayer <mayer@pdmconsulting.net> schrieb am 20.09.2022 um 15:37 in
Nachricht <23f26126-c39e-16ea-d862-c8ac706e37d5@pdmconsulting.net>:

...
>> Can you please tell us in which file and on what line we can see that
>> difference in handling of measurements made in client/server mode and
>> symmetric mode?
> 
> It's in there. If you don't want to read code you can read some of Dave 
> Mills's papers. Here's one document reference and I'm sure that you can 
> search for others. His book also talks about it.
> 
> https://doc.ntp.org/reflib/onwire/ 

Having the RFCs, the source code of the reference implementation, and the Mills paper, does not make things easier.
Ideally the RFCs would cover everything one needs to know.

...

Regards,
Ulrich

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