Nippon Telegraph and Telephone Corporation

Tomoo Fukazawa

Masami Urano

Yukio Tsuruoka

Yoshinao Kikuchi

Ken Takeya

A secret information serveron a networkand a client apparatusconstitute an authentication information generating system. The secret information serverhas a function to confirm the validity of a user in accordance with user identification information received from the client apparatusand a function to hold the secret information database of each user and to send the secret information database of a user whose validity has been confirmed to the client apparatusof the user. The client apparatushas a main memoryhaving a domain A where an application or a main OS is executed and a domain B which has a program execution environment mutually independent of that for the domain A. The secret information database received from the secret information serveris saved in the domain B, and authentication information is generated by using the secret information database. Secret information required to generate the authentication information for user authentication is held securely at low cost.

Authentication information generating system, authentication information generating method, client apparatus, and authentication information generating program for implementing the method

The present invention discloses a method for randomizing a microprocessor system, such as an IC card, in order to prevent the microprocessor system from being tampered with. The method ensures that the randomized microprocessor system realizes a functionality equivalent to that of an original microprocessor system and enables easy modification of a configuration of the microprocessor system. In the context of this disclosure, to randomize a microprocessor system means to randomize a microprocessor and a program included in the microprocessor system while maintaining an equivalence of functionality realized by the microprocessor system regardless of this randomization. According to the present invention, the method for randomizing a microprocessor system performing a given functionality consists in (a) randomizing items stored in a memory in accordance with randomizing information, and (b) randomizing a microprocessor so as to allow the microprocessor to have an access to the randomized items stored in the memory. Thus, a randomized microprocessor system performing a functionality equivalent to the given functionality is generated.

Apparatus and method for modifying microprocessor system at random and maintaining equivalent functionality in spite of modification, and the same microprocessor system

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Tokyo, Japan

Tomoo Fukazawa