| 摘要 |
PURPOSE:To prevent a chargeable program from illegal use by adding a program identification signal. CONSTITUTION:A program discrimination signal 31 having prescribed corresponding relation between a ciphered program 21 and an initial value signal 71 is formed from an identification signal adding means 3 and these three signals are ciphered by a recording device 4 and recorded in a storage carrier 5. A signal to be a key deciphering the program 21 has been previously stored in a prescribed address of a nonvolatile storage device in an unshown user's terminal. When the storage carrier 5 is mounted on said user's terminal so that the user uses the compensated program 21, the signal to be the key deciphering the chargeable program 21 and stored in said nonvolatile storage device is read out by using the program identification signal 31 stored in the storage carrier 51 as an address signal. Thus, the chargeable program can be deciphered and executed by the key signal. |
