PURPOSE:To improve to hold the secrecy by changing hourly the password, and renewing freely a data converting table in the storing media of a host computer only by a terminal user CONSTITUTION:To password data, time data messages are added and the password is converted by the converting character data corresponding to the time data for at least one hour In this case, a means to renew freely the renewal of the converting character data stored in the data base of a host computer 2 by a terminal 3 side user is provided Then, the decoding for the password is not fixed as conventionally, but changed as the time passes, and the user of the terminal 3 can re-write the converting character used as the time passes Thus, the secrecy of the information for the unfair user can be held

Data communication system

A public key cryptographic system and method is provided for a password or any other predefined personal secret information that defeats key factoring and spoofing attacks. The method adopts a new technique of encrypting a password or any predefined secret information by a numeric function of itself, replacing the fixed public key of the conventional RSA encryption. The whole process involving key generation, encryption, decryption and password handling is discussed in detail. Mathematical and cryptanalytical proofs of defeating factoring and spoofing attacks are furnished.

Password self encryption method and system and encryption by keys generated from personal secret information

PROBLEM TO BE SOLVED: To provide a cipher processing device capable of preventing unauthorized registration by a determination device in a system for performing biometric authentication by comparing data obtained by encrypting biological information read from a user with encrypted registration data while maintaining an encrypted state.SOLUTION: A cipher processing device 10 holds a first key KA1 and receives authenticated data in the case of authentication. The cipher processing device 10 includes a communication section 11 and an arithmetic section 12. The communication section 11 communicates with a calculation device 20 in which encrypted registration data C2 are registered, the encrypted registration data C2 being obtained by double encrypting registration data mto be collated with the authenticated data with the first key KA1 and a second key KA2, and a determination device 30 that utilizes the second key KA2 in the case of authentication. When registering the encrypted registration data C2 in the calculation device 20, the arithmetic section 12 generates a key K different from the first key KA1, generates cipher data C1 by double encrypting the registration data mwith the first key KA1 and the different key K, transmits the different key K to the determination device 30 via the communication section 11 and transmits the cipher data C1 to the calculation device 20.

Program, cipher processing method, and cipher processing device

PROBLEM TO BE SOLVED: To activate a target application by safely performing a user authentication with a specified computer with simple configuration. SOLUTION: Concerning the user authentication method for plural computer systems connected by the Internet, the user authentication is performed by one specified computer and a pair of character strings of authentication data are enciphered while using time information as a key, and tranferred to the other computer.

User authentication method

PURPOSE:To prevent a password from leaking even when a communication line is intercepted by enciphering an inputted password based on the input time of the password, and transmitting an enciphered password to a central control unit via the communication line. CONSTITUTION:A timepiece 24 and a password enciphering means 13 which enciphers the password based on the input time of the password represented by the timepiece 24 are provided on a terminal 1. And the password enciphered by the password enciphering means 13 is sent to the central control unit 2 via the communication line 3. In other words, the password inputted to the terminal 1 is enciphered based on the input time by the password enciphering means 13, and is sent to the central control unit 2 via the communication line 3. In such a way, it is possible to prevent the password from leaking even when the communication line 3 is intercepted.

Watanabe Naomi

Papers

Password enciphering system