| 摘要 |
PURPOSE: To control access to broadcasting transmission by generating a seed used by a reception decoder in a card device containing a microprocessor device generating and transmitting data to be stored. CONSTITUTION: A verification unit 50 sends a data packet to a smart card 32 and generates a decoding seed and a display message on a screen. The verification unit 50 reads card identification number ID stored in the memory of the smart card. When an indication from a security protection computer, which is transmitted by a data packet, is given, the verification unit 50 and the smart card 32 execute a certifying process. The smart card 32 stores a card identification number, a second number and a modulus N stored in the verification unit 50 in it. Then, N is a public modulus being the multiple of two values P and Q, and P and Q are learnt only by a system generating the smart card. |
