The transferring of accumulated data from a plurality of vehicles to a data processing station involves transmitting a first packet type request from each vehicle via an open radio channel in response to a predetermined operation. This operation may consist of the vehicle's ignition being turned off. The first packet type is detected at a receiving station if a transmitting vehicle is within the vicinity of the receiving station. The receiving station transmits an instruction for data in the form of a second packet type upon detecting a first packet type. Thereafter, a portion of the accumulated data is transmitted from a detected vehicle in response to instructions generated by the receiving station.
