Method and equipment for encrypting/decrypting physical characteristic information, and identification system utilizing the physical characteristic information

• US 7,200,549 B1
• Filed: 05/31/2000
• Issued: 04/03/2007
• Est. Priority Date: 06/21/1999
• Status: Expired due to Fees

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Shinzaki, Takashi, Fujii, Yusaku
• Primary Examiner(s): Moise; Emmanuel
• Assistant Examiner(s): Tran; Tongoc
• Application Number:
  US09/583,882
• Time in Patent Office: 2,498 Days
• Field of Search: 713164-171, 713189-194, 713/161, 713200-202, 713184-186, 382/115, 340/5.1
• US Class Current: 713/161
• CPC Class Codes: H04L 63/0428 wherein the data content is protected, e.g. by encrypting or encapsulating the payload
• CPC Class Codes: H04L 9/08 Key distribution or management, e.g. generation, sharing or updating, of cryptographic keys or passwords network architectures or network communication protocols for supporting key management in a packet data network H04L63/06
• CPC Class Codes: H04L 9/0822 using key encryption key
• CPC Class Codes: H04L 9/32 including means for verifying the identity or authority of a user of the system or for message authentication, e.g. authorization, entity authentication, data integrity or data verification, non-repudiation, key authentication or verification of credentials
• CPC Class Codes: H04L 9/3231 Biological data, e.g. fingerprint, voice or retina network architectures or network communication protocols for supporting authentication of entities using biometrical features in a packet data network H04L63/0861

Abstract

A cryptographic method and equipment decrypting a cryptographic key by generating an auxiliary code based on a randomly determined numeric key and including a result of encryption into a cryptogram. Upon decryption, the cryptographic key is restored using the numeric key restored according to the entire cryptogram. A cryptographic method and equipment scrambles and encrypts physical characteristic information, and descrambles a result of a decryption, thereby enabling any alteration to a cryptogram to be detected because even a minor alteration thereto changes the result of the decryption. A remote identification system encrypts physical characteristic information using a password as a cryptographic key, and fluctuation of the physical characteristic information, authenticating information represented as a different bit pattern at each identifying processing is generated and sent to a transmission medium.

Claims

1. A cryptographic method comprising:

receiving physical characteristic information representing a characteristic inherent to an individual;

randomly determining a numeric key;

generating a cryptographic key from said numeric key and a predetermined primary key;

encrypting said physical characteristic information using said cryptographic key; and

generating an auxiliary code for decrypting said cryptographic key, from said encrypted physical characteristic information and said numeric key.

2. A decryption method comprising:

receiving encrypted physical characteristic information and an auxiliary code;

restoring a numeric key from said received encrypted physical characteristic information and said auxiliary code;

restoring cryptographic key from said numeric key and a predetermined primary key; and

decrypting said encrypted physical characteristic information by using said cryptographic key and obtaining physical characteristic information.

3. A cryptographic equipment, comprising:

an inputting unit inputting physical characteristic information representing a characteristic inherent to an individual;

a numeric key generating unit randomly determining numeric key;

a key generating unit generating a cryptographic key from said numeric key and a predetermined primary key;

an encrypting unit encrypting said physical characteristic information using said cryptographic key; and

a code generating unit generating an auxiliary code from said encrypted physical characteristic information and said numeric key.

4. A decryption equipment comprising:

a receiving unit receiving an encrypted physical characteristic information and an auxiliary code;

a numeric key restoring unit restoring a numeric key from said encrypted physical characteristic information and said auxiliary code;

a key generating unit generating a cryptographic key from said numeric key and a predetermined primary key; and

a decrypting unit decrypting said encrypted physical characteristic information by using said cryptographic key.

5. A storage media storing a program to read and be executed by a computer, comprising:

an inputting procedure inputting physical characteristic information representing a characteristic inherent to an individual;

a numeric key generating procedure randomly determining a numeric key;

a key generating procedure generating a cryptographic key from said numeric key and a predetermined primary key;

an encrypting procedure encrypting said physical characteristic information using said cryptographic key; and

a code generating procedure generating an auxiliary code from said encrypted physical characteristic information and said numeric key.

6. A storage media storing a program to read and be executed by a computer, comprising:

a receiving procedure receiving a cryptogram including an encrypted physical characteristic information and an auxiliary code;

a numeric key restoring procedure restoring a numeric key from said encrypted physical characteristic information and said auxiliary code;

a key generating procedure generating a cryptographic key from said numeric key and a predetermined primary key; and

a decrypting procedure decrypting said encrypted physical characteristic information by using said cryptographic key.