| 摘要 |
PURPOSE:To form and distribute data enciphering keys having high cipher intensity at a high speed by arranging data enciphering keys in plural blocks in a master station and a slave station in common and informing a key in a selected block to be used to the terminating side by a command every cipher communication. CONSTITUTION:A cipher processing part 4 receiving a random number forming command from a central processing part 1 finds out exclusive OR between the initial value IV0 of an IV register 43 and the counting value C of a binary counter 44 at that time and generates key data indicated by the equation 1 shown in figure. When the key data are set up in a DES algorithm processing part 48 and said IV0 is inputted to the processing part 48, the random number data RN0 of the 1st block which are enciphered by the key K0 are outputted from the processing part 48, inputted to the register 43 and transferred to a memory 2. Then, random number data RN1-RNn are generated by the similar procedure on the basis of the RN0 and these data RN1-RNn are used as data enciphering keys. |
