In the partial dispersion information generation means where the distributed information generation device and the classified information restoration device, the generation method of information of the distribution which accompanies authority information, it has

摘要

PROBLEM TO BE SOLVED: To achieve access control with a simple configuration by using a threshold secret sharing scheme wherein an exclusive OR is used.;SOLUTION: A partial distributed information generating means has a secret information input section for inputting secret information and a random number input section for inputting random numbers, performs an exclusive OR (XOR) operation of the input secret information and random numbers, and generates partial distributed information. Authority information which generates random numbers when restoring secret information is made to correspond to predetermined number of pieces of information composed of random numbers and secret information as one unit and input in the secret information input section and the random number input section, distributed information is generated by combining, by a combining means, the partial distributed information output from the partial distributed information generating means, and the generated distributed information and authority information are transmitted from a transmitting section to an administrator having prescribed authority.;COPYRIGHT: (C)2009,JPO&INPIT