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Re: [Ntp] Routing asymmetries in v5

Daniel Franke <dfoxfranke@gmail.com> Mon, 13 April 2020 14:45 UTC

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From: Daniel Franke <dfoxfranke@gmail.com>
Date: Mon, 13 Apr 2020 10:44:52 -0400
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To: Watson Ladd <watsonbladd@gmail.com>
Cc: NTP WG <ntp@ietf.org>
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Subject: Re: [Ntp] Routing asymmetries in v5
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On Sun, Apr 12, 2020 at 9:42 PM Watson Ladd <watsonbladd@gmail.com> wrote:

> It seems that corrections are discarded if asymmetric and I don't
> think this is necessary. If we have all the boxes speaking NTPv5
> corrections, then the routing delay in the boxes should be compensated
> out and the correction field will properly adjust the measurements.
> Maybe I'm missing something.

I don't think "all the boxes speaking NTPv5 corrections" is something
that's ever likely to happen. The situation I was worried about when I
added the CRC stuff is that boxes on one path are doing corrections
and the ones on the other aren't, in which the case the correction is
going to make the asymmetry worse as often as it makes it better. But
maybe you're right; I think this is an issue that would benefit from
implementations and experiments.

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