Encryption key distribution system, key distribution ecu and key reception ecu

A key distribution electronic control unit (ECU) that transmits an encryption key to a key reception electronic control unit (ECU), the key distribution ECU comprising:

• a first memory;
• and
• a first processor coupled to the first memory and configured to:
• transmit the encryption key to the key reception ECU including a second memory and a second processor;
• receive, from the key reception ECU, first verification data of the transmitted encryption key, the first verification data being calculated from a common key held by the key reception ECU and an identifier of the key reception ECU;
• and
• determine completion of transmission of the encryption key to the key reception ECU, based on a result of determination as to whether the received first verification data matches second verification data of the encryption key, the second verification data of the encryption key being calculated from the same common key as the common key which is stored in the key distribution ECU and the identifier of the key reception ECU.

A key reception electronic control unit (ECU) that receives an encryption key from a key distribution electronic control unit (ECU) that transmits the encryption key, the key reception ECU comprising:

• a first memory;
• and
• a first processor coupled to the first memory and configured to:
• record the encryption key which is received from the key distribution ECU including a second memory and a second processor in the first memory;
• calculate first verification data of the received encryption key from a common key which is stored in the first memory and an identifier of the key reception ECU;
• and
• transmit the calculated first verification data to the key distribution ECU.