COMPUTER DATA PROTECTION SYSTEM BY ENCRYPTION

PROBLEM TO BE SOLVED: To provide a means for preventing information from being stolen even when a physical key and a personal computer are stolen at the same time in a system wherein a physical key for permitting use of a software program for encryption/decryption is provided in addition to use of a physical key and encryption/decryption of data for taking countermeasures against leakage, missing or a theft of confidential data such as personal information. SOLUTION: The means above disclosed herein is a data encryption/decryption system comprising an encryption/decryption program, a computer for installing the program, an external connection element to the computer for permitting the decryption of the program, and a program for providing a decryption operation permission right to the external connection element. Entry of decryption operation permission password of the encryption/decryption program can be requested, entry of connection of the external connection element to the computer for installing the right provision program or entry of the connection and right provision program operation permission password can be requested. Various conditions can be provided to a decryption operation permission key. COPYRIGHT: (C)2008,JPO&INPIT