On Thu, Aug 14, 2014 at 1:24 AM, Chris Barker <ftog@xxxxxxxxxxxxxx> wrote:
..
> I somehow doubt that a networked device will show you time that is accurate
> to the second, however accurate the network itself has to be. There is
> surely too much latency in the system.
NTP (network time protocol) deals with the latency.
http://tools.ietf.org/html/rfc5905
The basic idea is send a query to a server, record the time you wait,
get a response. Say it takes 20 msec from query to response; add
20/2=10 msec to received time and use the result. If you need better
accuracy, use several queries, possibly to different servers, and
average the results.
This is definitely not perfect, but it gives useful results -- much
better than 1 s accuracy -- in most cases. If you need something
better, like millisecond accuracy, a Rasberry Pi with a GPS attachment
can provide an NTP server on your network for not a lot of money.
--
_________________________________________________________________
Options: http://lists.thomasclausen.net/mailman/listinfo/olympus
Archives: http://lists.thomasclausen.net/mailman/private/olympus/
Themed Olympus Photo Exhibition: http://www.tope.nl/
|