JPH09245139A - Authenticating type security system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively prevent the forgery and the duplication of an object by confirming the legality of identification data only by autographic data generated based on reference data obtained by a prescribed machine from a reference area difficult to produce the same thing. SOLUTION: With respect to identification data M' among data W' with autograph obtained from a magnetic stripe 3, hashing processing is executed to obtain hashed data D'. Autographic data S' among data W' with autograph is simultaneously inverse-transformed by a multivariable polynomial tuple Q to separate them into hashed data D" and random data R' each. Two hashed data D' and D" obtained like this are compared with each other to inspect the autograph to check the presence/absence of the alteration, etc., of data. At the same time of this, identification data M' is separated into reference data F' and managing data A' to compare identification data F' with reference data F" obtained from a reference area to check the presence/absence of the alteration, etc., of data.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a security system for preventing forgery and duplication of an object such as a prepaid card, a credit card, an ID card, etc., which requires judgment of authenticity.

[0002]

2. Description of the Related Art As a means for preventing counterfeiting or copying of an object, for example, physical characteristics peculiar to the object are recorded as data, and this data is compared with the actual physical characteristics to verify the authenticity. Although various methods have been proposed for determining the above, it is not impossible to scrutinize, analyze, and duplicate the unique characteristics.

Further, one of the conventional security systems
As one method, there is known an authentication system in which signature data is generated from original data using a signature generation rule and the signature data is inspected using a signature inspection rule to confirm the authenticity of the original data. According to this system, a person who knows the signature inspection rule can inspect the signature data and confirm the authenticity of the original data. Also, only those who know the signature generation rule can generate their own signed data,
The data can be modified. Since the authenticity of the data can be effectively determined by this system, a mechanism for attaching the data recording medium to the object such as by sealing it and guaranteeing the authenticity has also been attempted.

However, in this system, it is not possible to prevent dead copying of signed data, and it is also necessary to obtain a plurality of samples of signed data and original data for illegal purposes. Analysis of
It is not impossible to decipher the signature generation rule to newly generate signed data or falsify the data.

[0005]

SUMMARY OF THE INVENTION In view of the problems of the prior art as described above, the main object of the present invention is to effectively prevent the forgery and duplication of an object and provide a highly safe security system. It is in.

[0006]

According to the present invention, there is provided a security system for preventing forgery and duplication of an object which requires the determination of authenticity. A reference area that is readable but difficult to artificially create because it is generated randomly at random and identification data based on the reference data read from the reference area is stored and retained. And a signature data storage area for storing and holding signature data for authenticating the identification data, wherein the signature data is generated based on the identification data or the reference data. The authenticity is determined by comparing the reference data read at the time of the determination with the reference data included in the identification data or the signature data and the signature data. It is achieved by providing the authentication type security system, characterized in that is performed based on the authentication result of the identification data by.

As described above, the signature generated based on the reference data obtained by reading with a predetermined machine from the reference area where it is difficult to artificially produce the same thing, or the identification data to be collated by the reference data. Since the authenticity of the identification data stored and held in the identification data storage area can be confirmed only by the data, it is extremely difficult to analyze the signature generation rule by using, for example, a plurality of samples, and It becomes extremely difficult to newly generate signed data or falsify the data without knowing it. Moreover, even if only the signed data is simply dead copied, the authenticity is denied because the reference data is different for other objects, that is, the illegal application to other objects can be effectively prevented. .

In particular, the management data, which is information necessary for managing the object, is combined with the reference data to form identification data, so that the management data includes information about the object and the signature generator. If it is separately collated with, it is possible to more effectively prevent new generation of signed data and falsification of the data.

Further, since the signature data is generated based on the compressed identification data obtained by compressing the identification data, the bit length required for the processing can be suppressed and the time required for the signature inspection can be shortened. can do.

As the reference area, it is difficult to artificially reproduce the magnetic fibers which are randomly arranged in paper or resin, the unevenness of the paper is used, or the surface roughness of the sheet material is used. Moreover, any device can be used as long as it can be detected with good reproducibility by a predetermined machine. Examples of such a method include JP-A-6-168363 and JP-A-5-168363.
For example, those disclosed in Japanese Patent Laid-Open No. 2-33444 and Japanese Patent Publication No. 57-500851.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

FIG. 1 shows a prepaid card to which the present invention is applied. This card 1 is a polyester sheet 2
This card consists of a magnetic stripe 3 containing an identification data storage area for storing as identification data a combination of management data that specifies the issuer, ticket type and card usage, and reference data described below, and a frequency. There are provided a perforated region 4 to be perforated with the consumption of the magnetic field and a reference region 5 in which magnetic fibers are randomly dispersed in the resin of the base sheet 2. The magnetic stripe 3 further includes a signature data storage area described later.

FIG. 2 shows a card reader to which the present invention is applied. The card reader 10 includes a motor-driven roller for taking a card into a slot 11 and ejecting the card after reading the data.
2 are built-in. Along the slot 11, a magnetic head 13 for reading the magnetic stripe 3 and an inductive magnetic head 14 for reading the reference area 5 are provided. The reference numeral 15 designates a punching unit for sequentially punching the punching area 4 of the card to indicate the consumption of power, and punching the used reference area 5 to destroy the used reference area 5 if necessary. Show.

Next, with reference to FIG. 3, a signature data generation procedure of the card 1, that is, a card creation procedure will be described. First,
A signal is mechanically read from the reference area 5 along the reading locus set on the card reader side, and the signal is combined with the management data A as the reference data F.
Identification data M consisting of 4-bit data blocks m _{1 to} m ₄
Is written in the identification data storage area of the magnetic stripe 3. Next, a hashing process as shown in FIG. 4 is performed on the identification data M. That is, first, the data block m ₁ is fixed to the fixed 64-bit data block h ₀ ,
Combined with h ₀ ′, two 64-bit data blocks h ₁ , h ₁ ′ are obtained. The data block m ₂ is then combined with the 64-bit data blocks h ₁ , h ₁ ′ to obtain two 64-bit data blocks h ₂ , h ₂ ′.
These steps are repeated 4 times to obtain two 64-bit data blocks h ₄ and h ₄ ′. The finally obtained hashed data D has a data length of 128 bits.

As shown in FIG. 3, the hashed data D is combined with predetermined random data R to form input data Z of, for example, 100 bits, which matches the signature data length to be written. An affine transformation L, a bijective polynomial transformation P, and an affine transformation K are sequentially performed on this input data Z (Z → Y → X → S), that is, by the signature generation function G, the final signature data S is obtained. Then, it is written together with the above-mentioned recording data M in each storage area of the magnetic stripe 3. The entire data written in the magnetic stripe 3 in this manner is called signed data W. At this time, the signature data storage area and the identification data storage area may be arranged independently of each other, but may be data encrypted by an arbitrary encryption method not shown.

Here, the bijective polynomial transformation P transforms an arbitrary element Y on a finite field into an arbitrary element X. The difficulty of analyzing the signature generation rule is that multivariable simultaneous equations on the finite field are used. It is based on the difficulty of solving the equation. Further, affine transformation is performed before and after the transformation so that the signature generation function G will not be easily guessed from the signature check function V described later. Further, in h ₀ and h ₀ ′ in the hashing process, affine transformations L and K in the signature generation function G, and bijective polynomial transformation P,
Since it is possible to select arbitrary constants, various authentication systems can be formed, and it is difficult to estimate the signature generation rule. Further, since the random data R are connected at the time of signature generation, it is difficult to more effectively estimate the signature generation rule.

When this card 1 is used, first, as shown in FIG. 5, the identification data M'of the signed data W'obtained from the magnetic stripe 3 is processed in the same manner as described above. Hashing processing is performed and hashed data D ′
Get. At the same time, the signature data S'of the signed data W'is inversely transformed by the multivariate polynomial tuple Q (the above Z → Y
(Corresponding to the inverse conversion process of → X → S), that is, the inverse conversion is performed by the calculation by the signature check function V, and the hash conversion data D ″ and the random data R ′ are separated. By comparing the two hashed data D ′ and D ″, signature verification is performed and it is checked whether the data is forged or tampered with.

At the same time, the identification data M'is used as the reference data F '.
And management data A '. Here, the identification data F'is compared with the reference data F "obtained from the reference area by the inductive magnetic head 14 to check the authenticity of the card and the presence or absence of forgery or tampering of the data. Only when it is confirmed that the comparison results of'and D "and the reference data F'and F" are proper, that is, when the authenticity of the card is confirmed, the aptitude signal is output from the judging device and the applicability is determined. In addition to this, it also provides a predetermined service according to the management data A ′.
However, if it is confirmed that it is the same as the previously stored management data A (not shown), an aptitude signal may be output.

Since it is practically impossible to duplicate the same reference area as described above, it is possible to prevent dead copying of the card. Further, the reference data F ″ obtained from the reference area by the induction type magnetic head 14 has a different value each time it is read due to various factors such as card transportation, stop position error, contamination degree, and deterioration of magnetism over time.
Therefore, the authenticity of the card is checked based on whether or not the degree of coincidence exceeds a predetermined value. For example, even if the reference data F ′ is extracted from the identification data M ′ as magnetic data for the purpose of illegal use, the reference data F ″ is read from the reference area 5, and the two are compared to clarify the relationship between them, Because the reference data F ″ changes each time it is read for the above reason, the relationship cannot be specified even if a plurality of samples are used, and a card having an arbitrary reference area is illegally created, and the reference data F It is also extremely difficult to make the identification data M ′ corresponding to Moreover, since it is extremely difficult to create signature data based on the identification data, it is extremely difficult to falsify the data. Therefore, since it is extremely difficult to perform dead copy, forgery (copy), and data tampering with the card (object), it is virtually impossible to carry out fraudulent acts on the object.

In the above embodiment, the object is, for example, an information storage card or an ID card. However, it is possible to confirm that the object is an authentic one such as precious metals, securities, room or car keys, etc. It goes without saying that it can be arbitrarily applied to what needs to be proved.

[0021]

As described above, according to the present invention, an authentication system can be realized with signature data having a relatively small bit length, and it can be used in a simple magnetic recording medium.
In addition, the processing time required for signature generation and signature verification is short, and operation is possible at a speed and size that can be incorporated into a conventional card reader / writer, such as the size of programs and memory areas required for algorithm construction.

Since the reference data read from the reference area where it is difficult to artificially produce the same is compared with the identification data with a signature, it is extremely difficult to illegally copy the object card. Becomes Similarly, it is difficult to analyze the system from samples of multiple cards.

Furthermore, it is also difficult to analyze the signature generation rule from a card or a card reader, and it is possible to make the forgery and falsification of magnetic data that is relatively easy to copy extremely difficult. That is, even if a card reader (signature inspection machine) is illegally obtained and analyzed, it is extremely difficult to estimate the signature generation rule based on the difficulty of solving a multivariable simultaneous equation on a finite field. Thus, generation and modification of signed data can be effectively prevented.

[Brief description of drawings]

FIG. 1 is a front view showing a prepaid card as an example of a recording medium to which a system according to the present invention is applied.

FIG. 2 is a diagram showing an example of a card reader for a prepaid card.

FIG. 3 is a block diagram showing a procedure for creating a card according to the present invention.

4 is a block diagram showing details of a hashing process in FIG.

FIG. 5 is a block diagram showing procedures for card authentication and reading according to the present invention.

[Explanation of symbols]

 1 Card 2 Base Sheet 3 Magnetic Stripe 4 Perforation Area 5 Reference Area 10 Card Reader 11 Slot 12 Card Transport Unit 13 Magnetic Head 14 Inductive Magnetic Head 15 Perforation Unit

(72) Inventor Hiroyuki Matsumoto, 3-10, Fukuura, Kanazawa-ku, Yokohama, Kanagawa Prefecture, Japan 3-10 Fukuura, Japan (72) Inventor, Masataka, 3-10, Fukuura, Kanazawa-ku, Yokohama, Kanagawa Prefecture, Japan, Japan

Claims (4)

[Claims] 1. A security system for preventing counterfeiting and copying of an object that requires a determination of authenticity, the object being machine readable but physically generated at random. Therefore, it is difficult to artificially produce the same reference area, an identification data storage area for storing and holding identification data based on the reference data read from the reference area, and the identification data is authenticated. A signature data storage area for storing and holding signature data for storing the signature data, the signature data is generated based on the identification data or the reference data, and the authenticity determination is a reference read at the time of the determination. Data and
An authentication-type security system, which is performed based on a comparison result with reference data included in the identification data or the signature data and an authentication result of the identification data by the signature data. 2. The authentication type security system according to claim 1, wherein the identification data is data including management data for managing the object and the reference data. 3. The authentication security system according to claim 1, wherein the signature data is generated based on compressed identification data obtained by compressing the identification data. 4. The authentication type security system according to claim 1, wherein the reference area is formed by randomly arranging magnetic fibers in paper or resin.