FILE ACCESS AUTHENTICATION SYSTEM, FILE ACCESS AUTHENTICATION METHOD, AND FILE ACCESS AUTHENTICATION PROGRAM

摘要

PROBLEM TO BE SOLVED: To improve security in a file access authentication system.;SOLUTION: In a file access authentication system, a management device stores a present decoding key in a decoding key table in association with identification information, generates a new encoding key and a new decoding key, transmits the present decoding key associated with the received identification information and the new encoding key, and stores the new decoding key corresponding to the new encoding key, as the present decoding key, in association with the identification information received from a client device. The client device stores an encoded file in association with the identification information, receives the present decoding key and the new encoding key, deletes the present decoding key when the encoded file is decoded with the present decoding key thus received, generates a new encoded file by using the new encoding key thus received, stores the new encoded file thus generated in association with the identification information transmitted to the management device, and deletes the encoded file thus decoded and the new encoding key.;COPYRIGHT: (C)2009,JPO&INPIT