1. Field of the Invention
The present invention relates to a secret information protection system in an information processing system, more particularly, it relates to a secret information protection system to prevent access to, and utilization of, secret information stored in a storage means from an unauthorized person.
2. Description of the Related Art
Recently, portable information processing systems, such as a personal computer, a word processor, an electronic pocket notebook (denshi-tetyo in Japanese) and the like, have become wide spread in various fields for use in business and for personal use.
In general, a portable information processing system stores the secret information to be protected, for example, by a business. Accordingly, the secret information must be protected from being accessed by an unauthorized person.
As one example, in a communication system formed by a plurality of members (subscribers) each having a personal computer, each member has an identification code (ID code) or a password to utilize the secret information. In this case, the ID code or the password is usually stored in a storage unit of the personal computer. If the personal computer is stolen and the ID code or the password therein is decoded by an unauthorized person, the system may be illegally used by that person so that fee for use of the system is charged to an authorized member.
As another example, in general, a file or data base is coded by a key-code to protect the secret information stored therein. If the key code is stolen, the secret information can be easily accessed and utilized by an unauthorized person.