CENTRAL UNIT, ROAD TOLL SYSTEM AND METHODS FOR OPERATING A ROAD TOLL SYSTEM AND A CENTRAL UNIT

摘要

A method for operating a central unit (2) in a road toll system comprises sending a verification command or a software routine from the central unit (2) to an on-board unit (1), thereby instructing the on-board unit (1) to perform one or more defined actions and to transmit an answer to the central unit (2) that includes results of the defined actions. The method further comprises waiting for an answer from the on-board unit (1) in response to the verification command or software routine. If an answer is received from the on-board unit (1), the received answer is compared to an expected answer. The on-board unit (1) is classified as not trustworthy if no answer is received or if the received answer differs from the expected answer and the on-board (1) is classified as trustworthy if the received answer matches the expected answer.