[ntp:hackers] ntpd's sync state

Danny Mayer mayer at ntp.isc.org
Sun Jun 1 01:39:16 UTC 2008


Harlan Stenn wrote:
> Dave (et al),
> 
> There is a need to be able to easily and consistently determine if
> system clock and/or ntpd's idea of its internal state and the system
> clock are "correct" (for some definition of correct).
> 
> To offer this ability, it seems to me that the first thing we need to
> nail down is the definition and specification of "correct".
> 

The real problem with this is that there is no such thing as "correct"
since all the results are statistical in nature. That's the true nature
of things like offset and error budget. You have no hope of defining
such "correctness".

You also have the problem of define what the official reference time is 
since different countries have the own standards and reference points. 
In the US it's NIST in Boulder, Colarado, in the UK it's NPL in 
Teddington (I think), in France is the standards lab in Paris (I forget 
where), and so on.

Danny


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