Security system based on certification

• US 6,031,464 A
• Filed: 05/09/1997
• Issued: 02/29/2000
• Est. Priority Date: 05/08/1996
• Status: Expired due to Term

• Current Assignee: Matsumoto Tsutomu, NHK Spring Company Limited
• Original Assignee: NHK Spring Company Limited, Tsutomu Matsumoto
• Inventors: Matsumoto, Tsutomu, Ohno, Masatake, Matsumoto, Hiroyuki
• Primary Examiner(s): Louis-Jacques, Jacques H.
• Assistant Examiner(s): Beaulieu, Yonel
• Application Number:
  US08/853,523
• Time in Patent Office: 1,026 Days
• Field of Search: 340/825.31, 340/825.34, 382/115, 235/449, 235/380, 235/382, 235/382.5, 235/379
• US Class Current: 340/5.86
• CPC Class Codes: G07F 7/08 by coded identity card or credit card or other personal identification means without personal verification means G07F7/02
• CPC Class Codes: G07F 7/125 Offline card verification

Abstract

The data containing reference data is transformed into signature data by a method which depends on a variable generated by the reference data, and the identification data is certified by inverse transformation of the signature data. The signature generating rule changes in dependence on the reference data, and it is therefore extremely difficult to analyze the signature generating rule from the medium or the card reader/writer so that the forgery or modification of magnetic or other data, which is otherwise easy to duplicate, can be made extremely difficult. Therefore, even when a reader is illicitly obtained, and analyzed, it is extremely difficult to estimate the signature generating rule as it owes to the difficulty of solving a set of multivariate simultaneous equations.

Claims

1. A security system for preventing forgery or duplication of an object whose authenticity is required to be determined, comprising:

an identification data storage region for retaining identification data which is associated with a reference data, said reference data being individually assigned when writing said identification data into said identification data storage region; and

a signature data storage region for storing signature data for certifying said identification data;

wherein said signature data is generated by transforming data including said identification data and/or said reference data by using a first variable which is generated from said identification data and/or said reference data; and

the authenticity of said object is determined according to a result of certifying said identification data with data generated by inverse transformation of said signature data in a manner which corresponds to a second variable generated from said identification data and/or said reference data.

2. A security system based on certification according to claim 1, wherein said reference data is generated by reading data from a reference region which is affixed to said object and is machine readable, said identification region being formed in such a physically random fashion as to make any duplication of said identification region extremely difficult.

3. A security system based on certification according to claim 1, wherein the authenticity of said object is determined according to a result of matching said reference data read from said reference region during the course of an authenticity determination process with said reference data included in said identification data and/or said signature data, and a result of certifying said identification data with said data generated by inverse transformation of said signature data in a manner which corresponds to a second variable generated from said identification data and/or said reference data.

4. A security system based on certification according to claim 1, wherein said identification data consists of a combination of administrative data for managing said object and said reference data.

5. A security system based on certification according to claim 1, wherein said signature data is generated from a compressed identification data obtained by data compressing said identification data.

6. A security system based on certification according to claim 1, wherein said reference region is formed by randomly placing magnetic fibers in paper or synthetic resin material.

7. A security system based on certification according to claim 1, wherein said first variable is related to a constant of said transformation.

8. A security system based on certification according to claim 1, wherein said first variable is related to an algorithm for said transformation.

9. A security system based on certification according to claim 1, wherein said transformation comprises a bijection polynomial transformation.

10. A security system based on certification according to claim 1, wherein said transformation further comprises an affine transformation.

11. A method for authenticating an object, comprising:

affixing a reference data region to said object, said reference data region comprising a randomly formed physical marking that is difficult to duplicate and which is machine readable to generate unique reference data associated with said object;

reading the reference data region to generate the reference data associated with said object;

associating administrative data with said object, the administrative data including data relating to the provenance of said object;

combining the reference data and the administrative data to generate unique identification data associated with said object;

writing the identification data in a machine readable identification data storage region on said object;

hashing the identification data with an arbitrary constant to generate hashed identification data;

generating unique signature data associated with said object, comprising;

combining the hashed identification data with random data to generate input data;

selecting at least one constant;

operating on the input data with the at least one constant and a signature generating function to generate the signature data, the signature generating function comprising at least one bijection polynomial transformation; and

, writing the signature data generated in a machine readable signature data storage region on said object.

12. The method of claim 11, wherein the signature generating function further comprises at least one affine transformation.

13. The method of claim 11, wherein generating the signature data further comprises generating a unique variable from the reference data, and wherein selecting the at least one constant comprises deriving the constant from the generated variable.

14. The method of claim 11, wherein the administrative data associated with said object is stored remotely from said object as original administrative data, and further comprising:

reading the identification data from the identification data region on said object;

separating the administrative data from the identification data read;

retrieving the remotely stored original administrative data associated with said object; and

,

authenticating said object by comparing the administrative data read from said object with the retrieved original administrative data.

15. The method of claim 11, further comprising:

reading the identification data from the identification data storage region on said object;

separating the reference data from the identification data read;

reading the reference data from the reference data region on said object;

hashing the identification data read with an arbitrary constant to generate hashed identification data;

reading the signature data from the signature data storage region on said object;

inversely transforming the signature data read with a signature verifying function to generate hashed data combined with random data, the signature verifying function comprising at least one multivariate polynomial-tuple transformation;

separating the hashed data from the random data; and

,

authenticating said object by comparing the reference data separated from the identification data with the reference data read from the reference data region on said object, and by comparing the hashed identification data with the hashed data separated from the random data, respectively.

16. The method of claim 15 wherein inversely transforming the signature data with a signature verifying function further comprises:

generating a unique variable from the reference data read from the reference data region on said object;

deriving at least one constant from the generated variable; and

,

operating on the signature data with the at least one constant and the at least one multivariate polynomial-tuple to generate the hashed data.

17. The method of claim 13, wherein deriving the at least one constant from the generated variable comprises looking up the constant in a table defining a relationship between the variable and the constant.

18. The method of claim 11, further comprising compressing the identification data before hashing it.

19. The method of claim 11, wherein affixing a reference data region to said object comprises randomly distributing a plurality of magnetic fibers in a matrix of non-magnetic material and attaching the matrix to said object.

20. The method of claim 15, further comprising generating a "good" signal when said object is determined to be authentic.