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

• US 7,962,754 B2
• Filed: 06/07/2005
• Issued: 06/14/2011
• Est. Priority Date: 06/21/1999
• Status: Expired due to Fees

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Fujii, Yusaku, Shinzaki, Takashi
• Primary Examiner(s): Homayounmehr; Farid
• Assistant Examiner(s): Tran; Tongoc
• Application Number:
  US11/145,925
• Publication Number:
  US 20050229009A1
• Time in Patent Office: 2,198 Days
• Field of Search: 713/186, 713/161, 713183-185, 382/115, 382/276, 382/278
• US Class Current: 713/186
• 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 equipment comprising:

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

a scrambling unit arithmetically converting each of a plurality of data blocks obtained by dividing said physical characteristic information into a predetermined length of data by using a predetermined reversible function concerning a data block to be converted and a plurality of data blocks having predetermined positional relationships including a positional relationship being adjacent to the data blocks to be converted or a positional relationship being separated from the data blocks to be converted by a predetermined number of the data blocks, and scrambling said physical characteristic information; and

an encrypting unit encrypting the scrambled physical characteristic information for every said predetermined length of data by using a cryptographic key of a predetermined length, where the cryptographic key is stored in a cryptographic key storage area, and

wherein the scrambling of said physical characteristic information occurs prior to the encrypting and the predetermined reversible function is Fourier transformation, and

the cryptographic key subsequent to the Fourier transformation is dependent on all of each of said plurality of data blocks components of the physical characteristic information.

2. A non-transitory storage media storing a program to read and be executed by a computer, comprising:

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

a scrambling procedure arithmetically converting each of a plurality of data blocks obtained by dividing said physical characteristic information into a predetermined length of data by using a predetermined reversible function concerning a data block to be converted and a plurality of data blocks having predetermined positional relationships including a positional relationship being adjacent to the data blocks to be converted or a positional relationship being separated from the data blocks to be converted by a predetermined number of the data blocks, and scrambling said physical characteristic information; and

an encrypting procedure encrypting the scrambled physical characteristic for every said predetermined length of data information by using a cryptographic key of a predetermined length, where the cryptographic key is stored in a cryptographic key storage area of the computer, and

wherein the scrambling of said physical characteristic information occurs prior to the encrypting and the predetermined reversible function is Fourier transformation, and

the cryptographic key subsequent to the Fourier transformation is dependent on all of each of said plurality of data blocks components of the physical characteristic information.

3. A cryptographic method comprising:

reading physical characteristic information representing a characteristic inherent to an individual and inputting said physical characteristic information to a computer;

arithmetically converting each of a plurality of data blocks obtained by dividing said physical characteristic information into a predetermined length of data by using a predetermined reversible function concerning a data block to be converted and a plurality of data blocks having predetermined positional relationships including a positional relationship being adjacent to the data blocks to be converted or a positional relationship being separated from the data blocks to be converted by a predetermined number of the data blocks, and scrambling said physical characteristic information; and

encrypting the scrambled physical characteristic information for every said predetermined length of data by using a cryptographic key of a predetermined length, where the cryptographic key is stored in a cryptographic key storage area of the computer, and

wherein the scrambling of said physical characteristic information occurs prior to the encrypting and the predetermined reversible function is Fourier transformation, and

the cryptographic key subsequent to the Fourier transformation is dependent on all of each of said plurality of data blocks components of the physical characteristic information.