Abstract: A prescribed virtual person was created for allowing a real person (user) in the actual world to pretend to be the virtual person (virtual person) and act as the virtual person when acting on a network and registered in a database 12a of a financial institution 7 for enabling the user to make shopping or the like as the virtual person with an electronic certificate issued by the financial institution 7 for the virtual person when pretending to be the virtual person and acting on the network, and the address of the virtual person necessary as the destination of a purchased article was set to a nearby convenience store. When acting on the network as the virtual person, cookies are rendered easily acceptable as compared with the case of the real person.

Abstract: A prescribed virtual person was created for allowing a real person (user) in the actual world to pretend to be the virtual person (virtual person) and act as the virtual person when acting on a network and registered in a database 12a of a financial institution 7 for enabling the user to make shopping or the like as the virtual person with an electronic certificate issued by the financial institution 7 for the virtual person when pretending to be the virtual person and acting on the network, and the address of the virtual person necessary as the destination of a purchased article was set to a nearby convenience store. When acting on the network as the virtual person, cookies are rendered easily acceptable as compared with the case of the real person.

Abstract: A personal identification device 1 comprises a fingerprint sensor 1a that detects a fingerprint; and a scanner 1b that calls a storage medium 2 mounted on a portable device 3 worn on a finger, a wrist, or an ankle of a user for reading recording information stored on the storage medium 2. The fingerprint sensor and the scanner are integrally provided in a device main body of the personal identification device. The personal identification device further comprises fingerprint comparison means 1c for comparing fingerprint data of a user's finger detected by the fingerprint sensor 1a with fingerprint comparison data read by the scanner 1b from the storage medium 2 of the portable device 3 worn on the finger or the wrist of the user. The fingerprint comparison means 1c identifies that the holder of the storage medium is an authentic user based on a match between the fingerprint data and the fingerprint comparison data.

Abstract: A prescribed virtual person was created for allowing a real person (user) in the actual world to pretend to be the virtual person (virtual person) and act as the virtual person when acting on a network and registered in a database 12a of a financial institution 7 for enabling the user to make shopping or the like as the virtual person with an electronic certificate issued by the financial institution 7 for the virtual person when pretending to be the virtual person and acting on the network, and the address of the virtual person necessary as the destination of a purchased article was set to a nearby convenience store. When acting on the network as the virtual person, cookies are rendered easily acceptable as compared with the case of the real person.

Abstract: In a communication system, a transmitter device encrypts variable-length data having a data length corresponding to a kind of information to be transferred or a communication capacity, using a natural random number, to produce a variable-length random number sequence. Then, the transmitter device performs an exclusive OR operation per bit between the variable-length random number sequence and the information to produce transfer information, and transmits the transfer information to a receiver device. The transmitter device further transmits the variable-length data and the natural random number in an encrypted manner to the receiver device. The receiver device reproduces the variable-length data and the natural random number transmitted in the encrypted manner, and then encrypts the variable-length data using the natural random number to produce a variable-length random number sequence which is identical with the foregoing variable-length random number sequence produced at the transmitter device.