Re: [Ntp] An RFC6921-compliant NTP implementation
Daniel Franke <dfoxfranke@gmail.com> Thu, 01 April 2021 15:05 UTC
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From: Daniel Franke <dfoxfranke@gmail.com>
Date: Thu, 01 Apr 2021 11:04:46 -0400
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To: Martin Burnicki <martin.burnicki@meinberg.de>
Cc: NTP WG <ntp@ietf.org>, bob.hinden@gmail.com
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Subject: Re: [Ntp] An RFC6921-compliant NTP implementation
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FTL is an annoyance for NTS if you have a common reference frame, and a
disaster if you don't. Suppose you have a client and server that are 25
light-milliseconds apart. If you get a response back 60 milliseconds after
you send your request, then in a subluminal universe you can deduce that
you're getting an error of at most 5ms on account of network asymmetry (I
don't think any NTP implementation supports this optimization, but byztimed
does). With no speed limit on communication, this trick doesn't work any
more and the error could be up to 30ms. With time travel, you can't bound
your error at all, because latencies can be negative.
On Thu, Apr 1, 2021 at 5:39 AM Martin Burnicki <martin.burnicki@meinberg.de>
wrote:
> Hi,
>
> On 2021-04-01 02:00 Daniel Franke wrote:
> > Building on the groundbreaking results from CERN's OPERA experiment
> > showing that neutrinos can be accelerated to superluminal speeds merely
> > by loosening the contacts on a transmission cable, I'm pleased to report
> > a mostly-successful experiment building an RFC6921 ("Design
> > Considerations for Faster-Than-Light (FTL) Communication") compliant
> > implementation of NTP.
> > [...]
>
> This sounds like a real cool improvement.
>
> I can imagine that "bad guys" will try to spoof this. Will it be
> possible to use NTS to avoid that? ;-)
>
> Martin
> --
> Martin Burnicki
>
> Senior Software Engineer
>
> MEINBERG Funkuhren GmbH & Co. KG
> Email: martin.burnicki@meinberg.de
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> Linkedin: https://www.linkedin.com/in/martinburnicki/
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- Re: [Ntp] An RFC6921-compliant NTP implementation Martin Burnicki
- [Ntp] An RFC6921-compliant NTP implementation Daniel Franke
- Re: [Ntp] An RFC6921-compliant NTP implementation Daniel Franke
- [Ntp] Antwort: An RFC6921-compliant NTP implement… kristof.teichel