摘要 |
A method for authenticating a vehicle-external device in a bus system of a motor vehicle comprising control units is provided. In order to effectively and inexpensively prevent a sequence control system that is stored in a control unit from being manipulated, an authentication device is provided in the bus system. The authentication device transmits an authentication request to the vehicle-external device. The vehicle-external device signs the authentication request with a secret key of an asymmetric pair of keys, such as a pair of public keys, and transmits the signed authentication request or exclusively the signature to the authentication device. The authentication device determines a signature of the authentication request using the same algorithm as the vehicle-external device, and decodes the signature transmitted by the vehicle-external device using the public key which is complementary to the secret key, and compares the determined signature with the transmitted signature. |