[time] GPS Time Server Survey
Thu Apr 24 22:32:49 UTC 2008
On Thu, Apr 24, 2008 at 3:20 PM, Jan Hoevers <ml.janhoevers at xs4all.nl> wrote:
> No way you can maintain that kind of accuracy with "a good crystal",
> even an oven controlled one would not do the job. And the average pool
> member will not sell his home to buy a cesium osc.
they're not that expensive. as i write this, there's one on ebay under
$2.5k. rubidiums are easily had under a thousand; the bare physics
package can be had for a couple hundred.
> What problem are you trying to solve anyway? We serve time over the
> internet, typically with an accuracy of 5 - 50 ms. That is
> milliseconds, not nanoseconds, not even microseconds.
"because i can"
note that i was the one who observed (twice) that there's ethernet
(and possibly ADSL) between any of my clients thereby seriously
impacting my accuracy.
> We have no need for a 30 ns reference, as it would be a million times as
> accurate as the service we can offer to the pool users.
but that doesn't stop me from wanting a 30ns reference.
> I do believe the pool will need more accuracy in the future, but right
> now the network is the bottleneck, not the time reference.
yes, i think this morning we all saw that the network sucks.
GDB has a 'break' feature; why doesn't it have 'fix' too?
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