US Patent 7228420 Method and system for technician authentication of a vehicle

The service technician accesses the prospective vehicle and obtains from a certification authority a certification that an authentic vehicle is associated with a cryptographic key. The service technician utilizes the cryptographic key in cryptographic communication with the prospective vehicle via a secure device having limited accessibility but being accessible by the service technician. The service technician determines whether the prospective vehicle is the authentic vehicle based on whether the cryptographic key is successfully utilized in the cryptographic communication with the prospective vehicle.