Abstract: The public-key encryption method uses the sender-side apparatus by the creator of a ciphertest and creates the ciphertext of a plaintext x (?{0, 1}n), in y1=f(x0k1G(r)), y2=H(x0k1G(r))r with respect to the published trapdoor-equipped unidirectional function f and the random functions G, H. Meanwhile, the receiver of the ciphertext, who has received the ciphertext by the receiver-side apparatus via the communications line, performs the decryption processing with the use of f?1, i.e., the secret key, in accordance with the steps inverse to those of the encryption processing.

Abstract: A fingerprint identification system comprising: an IC card having a tamper-resistance; and a reader/writer having a tamper-resistance for reading/writing information from/into the IC card. In the reader/writer, a fingerprint image, as read by a fingerprint input unit, is preprocessed in a preprocessing unit, and extracted intermediate information is transmitted to the IC card. This IC card compares the intermediate information with the fingerprint information, and makes authentication information usable for an electronic authentication upon matching. By this electronic authentication with applications, the fingerprint identification system, which has a high level of safety and can reduce the cost is provided.

Abstract: The public-key encryption method uses the sender-side apparatus by the creator of a ciphertest and creates the ciphertext of a plaintext x (? {0, 1}n), in y1=f (x0k1G(r)), y2=H (x0k1G(r))r with respect to the published trapdoor-equipped unidirectional function f and the random functions G, H. Meanwhile, the receiver of the ciphertext, who has received the ciphertext by the receiver-side apparatus via the communications line, performs the decryption processing with the use of f?1, i.e., the secret key, in accordance with the steps inverse to those of the encryption processing.

Abstract: A fingerprint identification system comprising: an IC card having a tamper-resistance; and a reader/writer having a tamper-resistance for reading/writing information from/into the IC card. In the reader/writer, a fingerprint image, as read by a fingerprint input unit, is preprocessed in a preprocessing unit, and extracted intermediate information is transmitted to the IC card. This IC card compares the intermediate information with the fingerprint information, and makes authentication information usable for an electronic authentication upon matching. By this electronic authentication with applications, the fingerprint identification system, which has a high level of safety and can reduce the cost is provided.

Abstract: The public-key encryption method uses the sender-side apparatus by the creator of a ciphertest and creates the ciphertext of a plaintext x (?{0, 1}n) in y1=f (x0k1G(r)), y2=H (x0k1G(r))r with respect to the published trapdoor-equipped unidirectional function f and the random functions G, H. Meanwhile, the receiver of the ciphertext, who has received the ciphertext by the receiver-side apparatus via the communications line, performs the decryption processing with the use of f?1, i.e., the secret key, in accordance with the steps inverse to those of the encryption processing.

Abstract: A fingerprint identification system comprising: an IC card having a tamper-resistance; and a reader/writer having a tamper-resistance for reading/writing information from/into the IC card. In the reader/writer, a fingerprint image, as read by a fingerprint input unit, is preprocessed in a preprocessing unit, and extracted intermediate information is transmitted to the IC card. This IC card compares the intermediate information with the fingerprint information, and makes authentication information usable for an electronic authentication upon matching. By this electronic authentication with applications, the fingerprint identification system, which has a high level of safety and can reduce the cost is provided.

Abstract: A security system wherein, when a staff enters a building, a smart card carried by the staff is verified, and staff information inclusive of a staff number and fingerprint information is read from the smart card and is stored temporarily in a temporary storage file. When the staff logs on to a terminal, the fingerprint of the staff is read by a fingerprint input device (LS) and verified with the fingerprint information of the temporary storage file for verification. When the staff leaves the building, the staff number is read from the smart card the staff carries, and the corresponding staff information is erased from the temporary storage file. Security of a security object inside a security zone can be improved.

Abstract: The public-key encryption method uses the sender-side apparatus by the creator of a ciphertest and creates the ciphertext of a plaintext x (∈{0, 1}n) in y1=f(x0klG(r)), Y2=H(x0klG(r))r with respect to the published trapdoor-equipped unidirectional function f and the random functions G, H. Meanwhile, the receiver of the ciphertext, who has received the ciphertext by the receiver-side apparatus via the communications line, performs the decryption processing with the use of f−1, i.e., the secret key, in accordance with the steps inverse to those of the encryption processing.

Abstract: A fingerprint identification system comprising: an IC card having a tamper-resistance; and a reader/writer having a tamper-resistance for reading/writing information from/into the IC card. In the reader/writer, a fingerprint image, as read by a fingerprint input unit, is preprocessed in a preprocessing unit, and extracted intermediate information is transmitted to the IC card. This IC card compares the intermediate information with the fingerprint information, and makes authentication information usable for an electronic authentication upon matching. By this electronic authentication with applications, the fingerprint identification system, which has a high level of safety and can reduce the cost is provided.

Abstract: A public-key cryptographic scheme of high efficiency capable of verifying security in a standard model. In order to retain security against adaptive chosen ciphertext attacks, a ciphertext is generated by a combination of a plaintext and random numbers so that an illegal ciphertext input to a (simulated) deciphering oracle is rejected.

Abstract: A cipher communication method by public key cryptosystem, being provably secure and highly efficient, wherein a sender generates ciphertext within a sender device using a receiver's public key and sends the ciphertext over a communication line, and a receiver decrypts the ciphertext using a secret key. For n=pdq (p and q are prime integers, and pq is k bits), a plaintext space is set to be a subset of an open set (0,2k−2) and small residue groups, and an algorithm is formed so that the relationship among solutions of plural second-order equations can be clarified. This has enabled security to be proved by equivalence with the difficulty of the problem of prime factorization, and has achieved faster decryption processing, compared with conventional methods.

Abstract: A data storing device for storing data subjected to dispersion processing is disclosed, in which input data are subjected to a dispersion processing by a convolution operation of the input data with a dispersion function, and dispersed data thus obtained are stored so that the initial input data are restored to be retrieved by the convolution operation of the dispersed data with the inverse function of the dispersion function.