Cost effective time servers

Eric S. Raymond esr at thyrsus.com
Mon Jun 24 18:17:37 UTC 2019


Patrick <nanog at haller.ws>:
> On 2019-06-20 20:18, Jay Hennigan wrote:
> > If you want to go really cheap and don't value your time, but do value
> > knowing the correct time, a GPS receiver with a USB interface and a
> > Raspberry Pi would do the trick.
> 
> https://www.ntpsec.org/white-papers/stratum-1-microserver-howto/
> 
> RPi + GPS Hat because time across USB has much jitter.

I wrote that white paper, and a good big chunk of the software in the recipe is mine.
The rest is about 25% percent of Dave Mills's reference implementation of NTP.

USB jitter isn't too bad, actually.  Unacceptable if you're doing pgysics experiments but
an order of magitude below the expected accuracy of WAN time synchronization.

That said, my recipe *is* better.  And a fun, simple, dirt-cheap build.
-- 
		<a href="http://www.catb.org/~esr/">Eric S. Raymond</a>





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