Acteiive Corporation

Crypto Basic Corporation

Tokyo University of Science Foundation

Satoshi Iriyama

Masanori Ohya

Luigi Accardi

Massimo Regoli

Maki Kihara

An encrypted data processing system is provided including an encryption device and a server. The encryption device includes an encrypting section that encrypts first information based on a first encryption key and transmits the encrypted information for registration to the server, and encrypts second information based on a second encryption key and transmits the encrypted information to be compared to the server. The server includes a comparison section that employs a cipher comparison function for comparing encrypted information to compare the encrypted information for registration against the encrypted information to be compared, and transmits a comparison result to the encryption device. The encryption device further includes a comparison result decrypting section that employs a decryption function for decrypting the comparison result with the first encryption key and the second encryption key to find a degree of matching between the first information and the second information.

Encrypted data processing system and program

Public data including a prime number p, a natural number d, a matrix Q, and a matrix S are acquired by a public data acquisition section, and secret key including natural numbers n, kis generated by a shared secret key generation section. A matrix M(M=SQS) is calculated by a non-commutative matrix generation section and transmitted to a communication party, and a matrix M(M=SQS) is acquired from the communication party. A matrix M(M=SMSk) is computed as a common secret key by a shared secret key computation section. An encryption/decryption device is thereby capable of rapid generation of the secure common secret key.

Common secret key generation device, encryption device, decryption device, common secret key generation method, encryption method, decryption method, and program

An encryption device generates non-commutative matrices A1, A2 based on private data A and prime numbers p1, p2, and operates the non-commutative matrices A1, A2 on vectors v, v. The encryption device performs non-linear transformation to transform the vectors v, vinto bit sequences, and joins these to the bit sequences W1, W2. The encryption device repeats the operation of the non-convertible matrices and the non-linear transformation until the respective numbers of bits of the bit sequence W1 and the bit sequence W2 have reached a number of bits of a bit sequence expressing encryption target data. The encryption device derives a pseudo-random number bit sequence by computing the exclusive logical sum between the bit sequence W1 and the bit sequence W2, and performs encryption using the pseudo-random number bit sequence. The encryption device is thereby able to increase the speed of encryption processing and to increase the cryptographic strength in cases in which the number of bits of the encryption target data is modifiable.

Growing community of inventors

Tokyo, Japan

Satoshi Iriyama