[ntp:questions] ESR looking for good GPS clocks

Michael Deutschmann michael at talamasca.ocis.net
Sat Mar 3 00:03:34 UTC 2012

I've recently noticed a post on celebrity hacker Eric S. Raymond's blog
that should be of interest here:


ESR has a project in mind that requires 100 special routers with
attached reference clocks that exceed NTP in quality.

He's run into the issue, often noted here, that there is a big price and
other deployment convenience differential between GPS devices that are
PPS capable and those that aren't -- despite the fact that the most
straightforward way to build a consumer GPS device involves a chip with
a PPS output pin.

So he's put out a call for someone, somewhere, to consider mass
producing a GPS suitable for timing, as he is about to produce a spike
in demand.

It's silly of him to ask only on his blog and not here, since many here
would want the same thing.  The only difference between what he wants
and the NTP hobbyist's dream is that he requires a USB interface.  An
NTP hobbyist would prefer raw RS-232 to cut conversion overhead, but ESR
wants to connect his reference clocks to router devices that only have
USB ports.  He claims to know the USB conversion impact and that his
error budget can take it.

(Not my dream though.  If I was to go to the trouble of installing a box
outside my home and routing a cable through the wall to my computers,
I'd like some weather sensors in the deal as well as just time...)

---- Michael Deutschmann <michael at talamasca.ocis.net>

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