Road toll system linking on board unit with vehicle

A road toll system comprising:

• a remote server in communication with a vehicle-mounted unit, wherein the vehicle-mounted unit and a unique identification device are installed within the same vehicle, the remote server comprising a satellite navigation system implementing a position tracking function, the remote server receiving position or route information of the vehicle from the vehicle-mounted unit,
• wherein the remote server is adapted to receive an odometer value for the vehicle when the system is installed or reset, and
• wherein the remote server is adapted to compute a distance travelled based on the received position or route information, and compare a new odometer value for the vehicle received from the vehicle-mounted unit with an expected odometer value for the vehicle based on the computed distance traveled,
• wherein the vehicle-mounted unit will not function if the unique identification device is not present and a mismatch between the expected odometer value and the new odometer value of the vehicle will accrue.