| 摘要 |
PROBLEM TO BE SOLVED: To prevent a situation as much as possible where security cannot be ensured due to leakage of a key to be used for cryptographic communication.SOLUTION: Cryptographic communication is carried out between a security chip (SC) and an IC by using a communication key 2-1. If recovery of a communication line is detected after detection of disconnection of the communication line with a game machine, authentication is implemented again with the game machine, the communication key is updated to a key 2-2, and the cryptographic communication is carried out by using the updated communication key 2-2. |
