Secret reconstruction method, distributed secret reconstruction device, and secret reconstruction system

摘要

PROBLEM TO BE SOLVED: To provide a secrecy reconstruction method, a distributed secrecy reconstruction device, and a secrecy reconstruction system for reconstructing the original secrecy information without disclosing the distributed information possessed by each member.;SOLUTION: The secrecy reconstruction method is the method for reconstructing the original secrecy information S by gathering t (2≤t≤n) members in such a case that first distributed information X_i (i=1, 2, ... , n) is generated from a certain secrecy information S and distributed to each member. When reconstructing the original secrecy information, each of the members gathered, while keeping the 1st distributed information X_i possessed by each of the members secret, disperses the 1st distributed information X_i by using the secrecy distribution method and distributes to each of other members as 2nd distributed information X_{i, j} (j=1, 2, ... , n), and receives the 2nd distributed information X_{i, j} from other members. The intermediate calculation result S_i for reconstructing the original secret information S is computed by distributed calculation, and the original secret information S is reconstructed from the intermediate calculation result S_i of each member.;COPYRIGHT: (C)2005,JPO&NCIPI