Need trusted NTP Sources

Jay Ashworth jra at
Sun Feb 9 20:16:25 UTC 2014

----- Original Message -----
> From: "Saku Ytti" <saku at>

> > In the architecture I described, though, is it really true that the
> > odds of the common types of failure are higher than with only one?
> I think so, lets assume arbitrarily that probability of NTP server not
> starting to give incorrect time is 99% over 1 year time.
> Then either of two servers not giving incorrect time is 0.99**2 i.e. 98%, so
> two NTP servers would be 1% point more likely to give incorrect time than one
> over 1 year time.

That's only true if the two devices have common failure modes, though,
is it not?
Jay R. Ashworth                  Baylink                       jra at
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