Patent ID: 8009828
Filing Date: 2011-08-30
Classification: G06Q,G07C,H04L

Abstract:
1. An integrated shuffle validity proving device having a central processing unit for executing processing using a program stored within a memory of the central processing unit, provided in correspondence to an order number k which is an integer indicating an order of a plurality of said integrated shuffle validity proving devices, forming part of a single shuffle validity proving device in harmony with integrated shuffle validity proving devices whose order number are different from the order number of itself, upon receipt of a mix net input cryptogram, for supplying a mix net output cryptogram which is a result of shuffling the mix net input cryptogram, and for supplying a same conversion knowledge proof commitment and a permutation proof commitment for proving a validity of a shuffle, and subsequently upon receipt of a challenge value for authentication, for supplying a response corresponding to said challenge value, said integrated shuffle validity proving device comprising: a permutation proof commitment device, on a public key for commitment being applied and upon receipt of a permutation storage commitment including permutation proof texts by said integrated shuffle validity proving devices with the order number from 1 to κ−1 from outside, for adding a permutation proof text generated thereby to said permutation storage commitment to generate a permutation proof commitment, for encrypting said permutation proof commitment with said public key for commitment, and for transmitting encrypted permutation proof commitment outside, wherein one or a plurality of said permutation proof commitment devices are provided, said integrated shuffle validity proving device comprises: a same conversion knowledge proof commitment device, upon receipt of a same conversion commitment base derived from a common reference base and assigned the order number κ, said input cryptogram sequence assigned the order number κ, and a random number, for generating and supplying a same conversion knowledge proof commitment assigned the order number κ; a response generating device, upon receipt of a challenge value assigned the order number κ and a random number, for supplying a response assigned the order number κ; and a permutation proof commitment integrating device, upon receipt of said permutation proof commitment assigned the maximum number which is the number of said plurality of integrated shuffle validity proving devices, said challenge value assigned the maximum number, and a distributed secret key assigned the order number κ, for generating a cryptogram of an integrated permutation proof commitment into which said permutation proof commitments are integrated, and for supplying distributed decryption of said cryptogram by said distributed secret key, and said one or plurality of permutation proof commitment device, upon receipt of said public key for commitment, said permutation storage commitment assigned the order number κ, and a random number, generates and supplies said permutation proof commitment comprised of cryptograms by said public key for commitment and assigned the order number κ.