On Saturday 28 December 2013 20:52 John Williamson wrote in uk.d-i-y:

On 28/12/2013 20:39, wrote:
dennis wrote:
The satnav may know which roads are closed, the map wont.

How does a satnav know that roads are closed? A satnav is
simply a map that knows dynamically where on the map it is,
it isn't psychic.

Some satnavs have a receiver for live(ish) traffic and road information.
It's normally piggybacked onto classic FM, IIRC.



Or it's running on a smartphone with 3G.
--
Tim Watts Personal Blog: http://squiddy.blog.dionic.net/

http://www.sensorly.com/ Crowd mapping of 2G/3G/4G mobile signal coverage