| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent, as much as possible, the inconvenience such that cryptocommunication has to be stopped thereafter when common factors of each other differ between both performing the cryptocommunication. <P>SOLUTION: A counter is added and updated (R, N, 0 to R, N, 1 to R, N, 2 to R, N+1, 0 to and so on) according to transmission and reception of cryptogram (operation instruction and operation response), and when counter updates on a main control part side and a CU communication control part side become inconsistent due to non-arrival of the operation response, a random number R is generated and transmitted as the operation instruction (Ek(R)) from a main control part to a CU communication control part, and both counters of the main control part and the CU communication control part are initialized (R, 0, 0). <P>COPYRIGHT: (C)2013,JPO&INPIT |
