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Re: [ntpwg] I-D Action: draft-ietf-ntp-checksum-trailer-02.txt

Miroslav Lichvar <mlichvar@redhat.com> Mon, 07 September 2015 13:22 UTC

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Date: Mon, 07 Sep 2015 14:49:42 +0200
From: Miroslav Lichvar <mlichvar@redhat.com>
To: Martin Burnicki <martin.burnicki@meinberg.de>
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Subject: Re: [ntpwg] I-D Action: draft-ietf-ntp-checksum-trailer-02.txt
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On Mon, Sep 07, 2015 at 10:28:12AM +0200, Martin Burnicki wrote:
> Miroslav Lichvar wrote:
> >I was thinking about detecting network asymmetries on the path between
> >client and server. If C1 and C2 are not equal, the paths were
> >different and the source could be rejected in the source selection or
> >have a smaller weight when combining with others.
> 
> On the other hand, if the delays in bot directions can be measured
> separately and this is done properly on the involved nodes then it shouldn't
> matter if the request and reply packets go over different routes.

I think the correction fields are supposed to include only the
processing delays. The NTP-aware devices generally can't know the
network delays between them.

-- 
Miroslav Lichvar
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