摘要:
A file processing unit comprises a first signature information producing unit that produces first signature information in accordance with a predetermined rule utilizing the data of a file designated by a file close request issued in an application used in a computer system, and a signature information storage control unit that stores the first signature information, correlated with the file designated by the file close request, in a storage unit.
摘要:
The authentication system has a signing station and a certifying station. The signing station divides the data to be transmitted into a plurality of data, a hash unit creates a plurality of authenticators by applying a different one-way function to each of the data. In the certifying station, a separating unit divides the data into a plurality of data, a hash unit creates a plurality of authenticators by applying a different one-way function to each data, and a comparing unit compares the authenticators prepared anew with the authenticators separated from the received data and checks the authentication of the data from the comparison.
摘要:
In a signature creating apparatus, a clock generates a time stamp and in which time can be set only by a computer installed in a certificate authority center. Further, connecting sections connects an apparatus ID for specifying an apparatus and the time stamp and personal identification information for identifying an implementor to a plain-text so as to create data for the signature. A signature creating circuit encrypts the data for the signature using a signature creating key or the like and generates the signature. A connecting section connects the signature to the data for the signature and transmits the data as data after signature.
摘要:
A cryptographic communication method is provided in which a cryptographic communication is performed by an easy operation even if both enciphered data and unenciphered data are mixed to be handled. In the transmission side, a communication key is used for enciphering data to be transmitted, and in the reception side the same communication key as in the transmission side is used for decoding received data. In the transmission side, an individual key that is different from the communication key is used for enciphering the data to be transmitted, the enciphered data are decoded by using the individual key first, and then the decoded data are enciphered by using the communication key so that the enciphered file can be transmitted.
摘要:
An information management method restoring electronic data using backup information upon the loss of electronic data stored on a recording medium. Information stored in a predetermined area of the recording medium having medium-specific information is encrypted using medium-specific information or a key generated therefrom and is derived outside the predetermined area.
摘要:
Before accepting a setting request from a predetermined manager in a plurality of date-and-time managers capable of issuing a date-and-time setting request, a setting request from any manager can be accepted. After accepting a setting request from a predetermined manager, only the setting request from the predetermined manager can be accepted. A date and time can be set in response to an accepted date-and-time setting request.
摘要:
A command authorization method that prevents a command issued by a third party from impersonating a command issued by a legitimate user, thereby maintaining high security. An authorization code stored in a command transmitted from a host is collated in a command authorization code parser. If the authorization code coincides with collating information therein, a command parser generates a predetermined access command, which is executed by a command controller.
摘要:
An electronic data protection system for protecting electronic data from illegal copying by a third party, includes: a storage medium for storing an encrypted electronic data, a medium number and encrypted permission information; a vendor computer having a personal key generating unit for generating a medium key based on the medium number, an electronic data decrypting key, and an encrypting unit for encrypting the electronic data decrypting key based on the medium key to generate the encrypted permission information; and a user computer having a personal key generating unit for generating a medium key based on the medium number, a decrypting unit for decrypting the encrypted permission information based on the medium key to generate the electronic data decrypting key which is the same as the electronic data decrypting key of the vendor computer, and a decrypting unit for decrypting the encrypted electronic data based on the electronic data decrypting key to generate a plain text electronic data.
摘要:
An encryption communication system including: a communication center having at least a key information generating unit for generating key generating information used for encryption communication; and a plurality of user computers, each interconnected by a plurality of paths through the communication center, and each having at least an encryption key generating unit and an encryption processing unit. The communication center generates the key generating information Z based on predetermined modulo arithmetic formula. The user computer sends a password PW to the communication center, receives the key generating information therefrom, and generates an encryption key K used between the user computer and another party's computer based on predetermined modulo arithmetic formula. Further, the communication center provides a plurality of modulus numbers to share prime numbers assigned to at least two paths between the user computer and the other party's computer, and between the user computer and another party's computer, so that is possible to reduce the number of prime numbers.
摘要:
A storage medium stores encrypted electronic data, a medium personal number which is unique for each storage medium and encrypted permission information. At least the medium personal number is written onto the storage medium in an un-rewritable form which a user computer cannot rewrite.