INFORMATION PROCESSOR, INFORMATION PROCESSING METHOD, INFORMATION PROCESSING SYSTEM AND PROVIDING MEDIUM

摘要

PROBLEM TO BE SOLVED: To prevent information from being copied illicitly. SOLUTION: A hash function and a service-key are stored in EEPROM 27 of a DVD player as a source. Its ID and license-key are stored in EEPROM 50 of a personal computer 2 as a sink. In a step 1, the player 1 requests the computer 2 for an ID. When it receives the supply of the ID, the player 1 applies a hash function to data (ID || service- key) that is acquired by connecting the ID and a service- key and acquires a key lk. Further, it creates a key of cryptograph sk and transmits data (e) that enciphers it with the key lk as a key to the computer 2. The computer 2 decodes the enciphered data (e) with the license- key as a key and acquires a key of cryptograph which is equal to the key sk.