[ntp:questions] Is dispersion > jitter in all situations

David Woolley david at ex.djwhome.demon.invalid
Tue Jan 5 21:20:26 UTC 2010


B wrote:

> I want to know the accuracy on a certain NTP-server at stratum 3. It
> is easy to calulate the absolute error bounds that wont be exceeded
> with this equation
> OFFSET +/- [DELTA/2 + DISPERSION]. This will in my case be OFFSET +/-
> 4 seconds, but I need to know more precise, ie an indicator of


In that case there is something wrong in your configuration! ntpd will 
start ignoring servers if their root distance is rather less than this 
and it would be an unusual system where the leaf nodes go so long 
between polls that they can accumulate the additional dispersion needed 
to reach 4 seconds.




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