Backgrounder on GPS accuracy, dGPS, aGPS etc http://www.theregister.co.uk/2011/03/10/rae_gps_report/ Jim -- datalude: information security e: jim at datalude.com Philippines: +63 2 403 1311 / mob: +63 917 849 3939 Hong Kong: +852 6840 6693 w: http://www.datalude.com/