[ntp:questions] Re: Philosophical question about strata

David Schwartz davids at webmaster.com
Thu Oct 13 19:02:30 UTC 2005

"Lee Sailer" <lee.sailer at direcway.com> wrote in message 
news:1129162116.801585.52900 at z14g2000cwz.googlegroups.com...

> First, thanks to everybody for replying.  However, my original question
> was not as clear as it could have been.  Let me continue...
> My company has 6 GPS time sources at various worldwide locations.  They
> are stratum 1.
> Every once in awhile, one or the other of them has a harddware problem.
> As a result, that one will drift a little.  That is, its offset will
> be 1, 2, or more seconds different from the other five.  When we detect
> this, we replce the hardware as a matter of course.
> Now, it seems to me that a stratum 2 server will never have this
> problem.  It gets time from several places, and uses the various
> algorithms to try to make sense.  The stratum 1 gets time from a bunch
> of satellites, and then if it screws up the calculation or has some
> sort of hardware glitch, then it is screwed.
> Therefore, I conclude:
> 1.  If everything is working, stratum 1 is better than stratum 2.
> 2.  If the stratum 1 hardware is suffering a slow degradation
> breakdown, then the stratum 2 will be better.
> Whaddya think 8-)

    I think you are using the word "better" without any clear notion of 
better for what purpose. A server that's either dead or or way off may be 
far more useful than a server that's slightly off -- if you're using 
multiple sources. (And you should be.)


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