| 摘要 |
PURPOSE:To eliminate the need for the control of an inherent key at the time of production of receiver and to reduce costs at the time of mass-production by constituting a part of a receiver so as to be detachable from a receiver main body. CONSTITUTION:First and second decoders and first and second memories are housed in a device 30 which is easily detachable from the pay television receiver main body. A first decoder 5 decodes an enciphered common key 17 by using an inherent key 18. A second memory 7 stores an enciphered common key 19, and a second decoder 4 decodes an enciphered scramble key 15 by using the common key 19. Thus, in the production of the receiver, a block 30 can be separated, for the pay television receiving device other than the block 30, the inherent key is unnecessary to be controlled, and a manufacture of a broadcast enterpriser is sufficient to control only the block 30 consisting of an IC card, etc. |
