<p>Hi Peter, all</p>
<p>Check out Tom Tom's Live Traffic product description - apparently this uses feedback from 80 million mobile phones and 1.6 million Tom-tom devices with their own mobile phone subsystem. Average speed trends on segments of road indicate whether the road is clear or congested.</p>
<p>Presumably the Dutch police were buying an additional service, that told them the actual average speeds. It seems like a good idea for the police to have detailed information so that they can issue warnings when a motorway is snarled up, or a traffic to/from a sporting event is causing disruption.</p>
<p>The Register article says the police identified roads with chronic speeding problems from the data, and targeted those roads with radar speed checks.</p>
<div class="gmail_quote">On 28 Apr 2011 01:50, "Peter Fairbrother" <<a href="mailto:zenadsl6186@zen.co.uk">zenadsl6186@zen.co.uk</a>> wrote:<br type="attribution"></div>