| 摘要 |
PROBLEM TO BE SOLVED: To prevent illegal copy of information. SOLUTION: An EEPROM 27 of a DVD player 1 as a source stores a hash function and a service- key. An EEPROM 50 of a personal computer 2 as a sink stores the ID and license0 key. A DVD player 1 requests an ID from the personal computer 2 (S1). At the time of receiving the ID, the DVD player 1 applies a hash function to data (ID ||service- key) obtained by connecting the ID with the service- key, and obtains a key lk. Moreover, the DVD player 1 generates a cryptographic key (sk), and transmits data (e) obtained by enciphering with the key (lk) as a key to the personal computer 2 (S8). The personal computer 2 decodes the encoded data (e) by using the license- key as a key, and obtains a cryptographic key (sk') equal to the cryptographic key (sk). |
