PROCESS FOR SECURING THE PRIVACY OF DATA TRANSMISSION

摘要

The method of secure data transmission between an immobilizer (1) of a motor vehicle's anti-theft device and a motor control unit (2) includes storing an internal key (20') in both immobilizer and the motor control unit; generating a random bit sequence (21) from existing sensor data in the motor control unit in response to a wake-up signal (24) from the immobilizer (1); transmitting the random bit sequence from the motor control unit to the immobilizer and storing it therein; producing a key code (22) with the random bit sequence (21) and the internal key (20') in both control units; encoding a message (23) including redundant data with said key code (22) in the immobilizer; sending the message (23) to the motor control unit; reading and checking the message (23) in the motor control unit by means of the redundant data contained in the message (23) to verify correct encoding and transmitting a release signal to the motor control unit when the encoding is correct.