JP4884052B2 - Biometric authentication system - Google Patents

Description

  The present invention relates to a biometric authentication system for registering biometric information acquired from a user and authenticating whether or not the user is the user by comparing the biometric information acquired from the user with the registered biometric information.

In recent years, interest in security, such as access control and access control to data and services, has increased. Under such circumstances, collation of biometric information represented by fingerprint collation is attracting attention as one of collation methods having a higher security level than password collation and card collation.
On the other hand, biometric information must be registered in advance in order to verify identity by collating biometric information, and biometric information that is one of the personal information is registered by the enforcement of the Personal Information Protection Law. There is a growing awareness of the dangers of being leaked from or stolen.
Therefore, a biometric authentication system has been proposed in which biometric information is divided to generate partial biometric information and register each partial biometric information in a different storage device to prevent the entire biometric information from being leaked or stolen at once. Yes.

In these conventional biometric authentication systems, biometric information is registered as follows.
In the invention described in Patent Document 1, biometric information is divided at a division rate determined based on a random number or a division rate designated by a user, stored in a storage unit and a portable storage unit, and synthesized at the time of collation.
In the invention described in Patent Document 2, the biometric information is divided into two parts by dividing the biometric information into blocks and dividing them into block numbers described in the distribution information and block numbers not described. One biometric information is registered in the portable storage carrier and the other is registered in the center device which is a storage device, and the biometric information is synthesized by referring to the distribution information at the time of collation. The distribution information is registered in the center device or the verification device.
In the invention described in Patent Document 3, authentication information finely divided at a plurality of division positions is assigned to the user database DB on the system side and the user terminal side, and synthesized by referring to the restoration key at the time of collation. A restoration key that is information on the division position is stored in the user database DB.

JP 2001-67137 A JP2002-351844 JP 2002-312317 A

However, in the prior art, there is a problem that a part of biological information, which is ultimate personal information that cannot be changed, can be leaked or stolen in a recoverable state.
That is, in the invention described in Patent Document 1, either a part of the biological information known to be the first half of the original biological information or a part of the biological information known to be the second half is leaked. Risk of being stolen or stolen.
In the invention described in Patent Document 2, if both the distribution information and the divided biometric information are leaked or stolen by an internal criminal who has access authority to the center device or the verification device, the distribution information There is a risk that a part of the biological information can be restored based on it.

Further, in the invention described in Patent Document 3, if both the restoration key and the divided authentication information are leaked or stolen by an internal criminal who has access authority on the system side, the biometric is based on the restoration key. There is a risk that part of the information can be restored.
In this way, the fact that a part of biometric information can be restored gives psychological resistance to users who entrust their biometric information to others, and provides security against internal crimes to businesses that manage the biometric information of users. It caused an excessive investment burden for strengthening.

  The present invention has been made to solve the above-described problem, and even if registered biometric information is leaked or stolen by an internal crime or the like, even part of the biometric information cannot be restored. An object is to provide a biometric authentication system having high confidentiality.

In order to solve such a problem, the present invention divides biometric information acquired from a user into a plurality of parts, registers them in different storage devices according to the distribution information, and restores the biometric information registered according to the distribution information and performs collation A biometric authentication system, a block forming unit that divides biometric information acquired from a user into a plurality of block data, a distribution information generating unit that generates distribution information that defines allocation of block data to a storage device, and distribution information Is divided into a predetermined number so that each becomes incomplete complementary data, and block data is distributed and stored in the storage device according to the distribution information, and the complementary data divided by the distribution information dividing means is predetermined. There is provided a biometric authentication system comprising registration means for separately storing a plurality of storage devices.

  According to such a configuration, the distribution information necessary for restoring the divided biological information is divided into incomplete complementary data and stored in each storage device. Therefore, the information stored in each storage device is stored in the information stored in each storage device. It is possible to make it difficult to partially restore the biometric information based on it, and to reliably reduce the risk of information leakage.

Further, it is preferable that the distribution information dividing means divides the distribution information into complementary data by distributing partial information of the distribution information.
According to such a configuration, the data size of the complementary data becomes smaller than the original distribution information, and an increase in communication amount and memory capacity when storing the complementary data in the storage device can be suppressed.

Further, it is preferable that the distribution information dividing means randomly selects one of a plurality of predetermined division patterns and distributes the partial information according to the selected division pattern.
According to this configuration, it is possible to eliminate the relationship between the complementary data and the distribution information, make it difficult to partially restore the biological information, and reliably reduce the risk of information leakage.

In addition, the distribution information dividing means randomly generates a bit string having the same number of bits as the distribution information as the first complementary data and calculates the second complementary data as an exclusive OR of the distribution information and the first complementary data. It is preferable.
According to this configuration, it is possible to eliminate the relationship between the complementary data and the distribution information, make it difficult to partially restore the biological information, and reliably reduce the risk of information leakage.

Furthermore, it is preferable that the blocking unit divides the block data into block data having a size smaller than the data size representing the characteristic portion of the biological information.
According to such a configuration, it is possible to increase the confidentiality of the divided biological information and reliably reduce the risk of information leakage.

According to the biometric authentication system of the present invention, the biometric information acquired from the user is divided according to the distribution information, and the distribution information is divided at random, and the divided biometric information and the divided distribution information are stored in separate storage devices. Since the information is stored, even if the divided distribution information is leaked together with the divided biological information, even part of the biological information cannot be restored.
Therefore, it is possible to reduce the management burden on the business operator who manages the psychological resistance of the user and the biological information of the user.

The biometric authentication system authenticates the user by registering and collating the user based on biometric information such as the face or fingerprint including the user's personality, fingerprint, vein, iris, palm shape, palm print, voice, handwriting, etc. It is. For example, it can be used when authenticating a user of an entry / exit management system, a data management system, a service providing system, or the like.
Hereinafter, a biometric authentication system according to an embodiment of the present invention will be described.

<First embodiment>
FIG. 1 shows an example of the configuration of the biometric authentication system according to the first embodiment.
The biometric authentication system communicates with the registration / verification terminal 1 in a contactless manner using a registration / verification terminal 1 for registering and collating biometric information, and an IC card used by a user and storing a part of the biometric information. And a storage device 3a, a storage device 3b,... That store part of the biometric information and communicate with the registration / verification terminal 1 via the communication network 4.

Next, the registration / collation terminal 1 will be described in detail with reference to FIG. FIG. 2 shows the configuration of the registration / collation terminal 1.
The registration / verification terminal 1 includes a biometric information acquisition unit 10, an input unit 15, a storage unit 11, a control unit 12, a communication unit 13, 3a with the storage device 2, a communication unit 14 with the storage device 3b,. Yes.
The biometric information acquisition unit 10 includes a camera that captures a facial image that is biometric information, acquires a user's face image, and outputs the acquired facial image to the control unit 12. In this embodiment, a camera is used to acquire a face image. However, the present invention is not limited to this, and is used with a sensor that reads a fingerprint or palm print, a microphone that records voice, a touch pen that reads handwriting, and the like. Depending on the biological information to be selected, it is appropriately selected.

The storage unit 11 is a memory device including a semiconductor memory, a magnetic disk, and the like, and includes a division pattern, a registration processing / collation processing program, various programs to be described later, intermediate results of the processing, and a storage device. 3a and various setting data such as addresses of the storage devices 3b are stored.
The division pattern is data that determines how the distribution information data is divided, and a plurality of division patterns are set and stored in advance. A division pattern ID is assigned to each division pattern, and the division pattern is stored in a state where search by the division pattern ID is possible (hereinafter referred to as a division pattern table).

The control unit 12 is a calculation / control device such as a DSP or LSI, CPU, MPU, etc., and inputs the acquired biometric information and executes registration processing / collation processing according to the program and settings. Is output.
The description in the control unit 12 indicates functional blocks of registration processing and collation processing among the programs stored in the storage unit 11.
That is, a user ID acquisition unit 120 that acquires a user ID for identifying a user input from the input unit 15 and a block division unit that divides the biological information acquired by the biological information acquisition unit 10 into a plurality of block data. 121, distribution information generating means 122 for generating distribution information for associating each block data with the storage device 2 and storage device 3 as distribution destinations, and selecting a division pattern for dividing the distribution information from the division pattern table Distribution information dividing means 123 for dividing distribution information according to the division pattern, biometric information dividing means 124 for dividing biometric information by distributing block data according to the distribution information, user ID and divided biometric information, divided Biological information for storing distribution information and divided division pattern IDs in the storage device 2 and the storage devices 3a, 3b,. Registration unit 125, divided division pattern ID and divided distribution information stored in storage device 2 and storage devices 3a, 3b,..., Registration information reading unit 126 for reading divided biological information, and division pattern Distribution information restoring means 127 for restoring the original distribution information from the division pattern ID and distribution information read with reference to the table, and a living body for restoring the original biological information from the biological information read according to the restored distribution information The information restoring means 128 and the biometric information matching means 129 for matching the biometric information acquired from the user who wants to obtain authentication with the restored biometric information are used, and registration processing and matching processing are performed using these means. Done.
Details of the registration processing and collation processing and details of processing executed by each means in these processing will be described later.
Note that some or all of these programs may be realized in hardware by a logic circuit.

The communication unit 13 is a card reader / writer, a USB interface circuit, or the like, and performs communication with the storage device 2 that is an IC card possessed by the user. Note that the communication unit 13 may employ either wired communication or wireless communication.
The communication unit 14 is a communication circuit having an interface unit with a communication network 4 such as a LAN, WAN, or the Internet, and performs communication with the storage devices 3a, 3b,.
The input unit 15 includes a key switch such as a numeric keypad, and is a user interface unit through which a user inputs a registration start instruction, a user ID, and the like.

Next, returning to FIG. 1, the storage device 2 will be described.
The storage device 2 is a portable storage device such as an IC card provided with a semiconductor memory or the like, a USB memory, or a flash memory card, and registers / verifies a user ID, divided biometric information, and divided distribution information. It is read from the terminal 1 and stored so as to be writable. The storage device 2 is owned by the user and used for registration / verification.

  The storage device 3a, the storage device 3b,... Are storage devices such as server devices installed in the management area, and store the user ID, the divided biological information, and the divided distribution information from the registration / verification terminal 1. It is possible to read from and write to the registration / verification terminal 1. The storage device 3a, the storage device 3b,... Are managed under strict security by the business operator.

(Operation at the time of registration in the first embodiment)
Next, the operation when the biometric authentication system according to the first embodiment registers the biometric information of the user will be described with reference to FIGS.
Further, in this example, it is assumed that an IC card that is the storage device 2 and stores an ID number for identifying the user is issued in advance, and the user carries the issued IC card. . The biometric information, the distribution information, and the division pattern ID are each divided into the division number N = 3, and the divided information is stored in the three storage devices of the storage device 2, the storage device 3a, and the storage device 3b. Is done.

When the user goes to the installation location of the registration / verification terminal 1 and operates the input unit 15 to instruct the start of registration, the registration process shown in FIG. 3 is started.
When the user approaches or attaches the IC card to the communication unit 13 which is a card reader / writer, the card reader / writer detects this and establishes communication with the IC card. When communication is established, the user ID acquisition unit 120 acquires the ID number stored in the IC card via the card reader / writer, and temporarily stores the acquired ID number in the storage unit 11.

  In step S310, the biometric information acquisition unit 10 captures the user's face to generate a face image, and extracts a plurality of feature portions related to the facial part from the face image. Then, biometric information composed of the data of the plurality of characteristic portions is temporarily stored in the storage unit 11. In this example, the biometric information acquisition unit 10 will be described assuming that 120 pieces of feature part data represented by 10 bytes are extracted and biometric information of L = 1,200 bytes is acquired. The data length L is an example, and an information amount suitable for collation is appropriately determined.

In step S320, the block dividing means 121 divides the biological information acquired by the biological information acquisition unit 10 into B blocks of M blocks, and temporarily stores the block information in the storage unit 11.
The block size B is preset to a value of 1 or more and less than L. M is determined from L and B, and M = [(L−1) / B] +1. However, [x] represents a floor function that gives a maximum integer less than or equal to x for a real number x.
The block size B is preferably set to be smaller than the data size for expressing the characteristic portion from the viewpoint of the confidentiality of the biological information. In other words, if the setting is made in this way, the data of the characteristic part is scattered.
The smaller the value of B, the better the confidentiality of the biometric information. On the other hand, the smaller the value of B, the larger the number M of blocks. This increases the data size of the distribution information and the storage device. Communication amount and the required memory amount of the storage device. Therefore, it is preferable to set the block size B as small as possible within the allowable range from the viewpoint of the communication amount with the storage device and the memory amount of the storage device.
In this example, a case where B = 3 and M = 400 are described. Reference numeral 400 in FIG. 4 exemplifies blocked biological information.

In step S330, the control unit 12 causes the distribution information generation unit 122 to generate distribution information that retains the correspondence between the blocks and the storage devices that store the respective block data.
Reference numeral 410 in FIG. 4 illustrates distribution information. The number of elements of the distribution information matches the number of blocks M, and the storage device number that is the value of each element is a numerical value from 1 to N that represents the storage device. In this example, “1” is stored in the storage device 2. A storage device number “2” is assigned to the device 3a, and a storage device number “3” is assigned to the storage device 3b. For example, the storage device number of the first element of the distribution information 410 being 3 means that the data of the first block is stored in the storage device 3b.
The distribution information generating unit 122 generates distribution information by randomly generating a numerical value of 1 or more and N or less M times.
The distribution information does not necessarily have to be randomly generated, and may be generated based on a predetermined rule, or the block data is equally distributed to each storage device with respect to the reliability in collation of block data. Distribution information may be generated.

In step S340, the distribution information dividing unit 123 divides the distribution information generated by the distribution information generating unit 122 by performing the following processing.
(1) A division pattern ID is randomly determined based on a random number. For example, it is assumed that the division pattern ID is determined to be 181.
(2) A division pattern associated with the division pattern ID determined by searching the division pattern table is selected and read. The division pattern is information that defines how the distribution information is divided.
Reference numeral 450 in FIG. 4 exemplifies the read division pattern. The number of elements of the division pattern matches the number of elements of the distribution information and is M. The value of each element is the above-described storage device number, and the storage device number defines which storage device stores each element of distribution information (specified by the distribution information element number in the figure).

(3) The selected division pattern is compared with the distribution information. If the two match, the process returns to (1) and the division pattern is selected again.
Since the division pattern is selected based on random numbers, it is uncorrelated with the distribution information. However, even if both coincide by chance, the correlation is completely eliminated by this process. This process is particularly effective when the number of blocks M is small.
(4) The distribution information is divided by distributing the elements of the distribution information generated by the distribution information generation means 122 according to the selected division pattern to N pieces of data.
460, 470, and 480 in FIG. 4 exemplify distribution information obtained by dividing the distribution information 410 according to the division pattern 450. The first distribution information 460 is assigned to the storage device 2. The distribution information 460 is data in which 3 which is the first element of the distribution information 410, 1 which is the second element of the distribution information 410, 2 which is the Mth element of the distribution information 410, and the like. The second distribution information 470 is allocated to the storage device 3a, and the third distribution information 480 is allocated to the storage device 3b.

(5) The determined division pattern ID is divided into N pieces of data. Specifically, the following processes (5-1) to (5-4) are performed.
(5-1) A binary number R1 having the same number of bits as the binary expression I of the division pattern ID is randomly generated.
For example, the division pattern ID is 8 bits. When the division pattern ID is 181, I = 10110101. It is assumed that 11001101 is generated as R1.
(5-2) The exclusive OR T1 is calculated for each bit of I and R1. At this time, the division pattern ID I is divided into two, R1 and T1.
In the above example, T1 = 0111000.
(5-3) A binary number R2 having the same number of bits as T1 is randomly generated.
Here, it is assumed that 10110110 is generated as R2.
(5-4) The exclusive OR T2 is calculated for each bit of T1 and R2. At this time, the division pattern ID I is divided into three, R1, R2, and T2.
In the above example, T2 = 11001110.
In this example, since N = 3, the division process ends when the division is performed into three, but when N is 4 or more, T2, as in (5-3) to (5-4). What is necessary is just to divide I into N by dividing T3.

  The distribution information divided into N pieces as described above is incomplete, and is complementary data in which the original complete distribution information cannot be restored unless all N pieces are collected. In addition, since the distribution information is divided according to a randomly selected division pattern, there is no relation between the contents of the distribution information and the method of dividing the distribution information, and the elements of the distribution information are derived from the contents of the divided distribution information. The order cannot be restored (part of the distribution information can be restored). Since a part of the distribution information cannot be restored, a part of the biological information divided according to the distribution information cannot be restored.

Further, the data size of the divided distribution information is a small data size of 1 / N of the original distribution information.
Further, the division pattern ID divided into N pieces is complementary data in which the original division pattern ID cannot be restored unless all N values are known.

  The distribution information divided by the above processing and the divided division pattern ID are temporarily stored in the storage unit 11.

In step S350, the biometric information dividing unit 124 acquires the biometric information acquisition unit 10 by distributing each block divided by the block dividing unit 121 to N pieces of data according to the distribution information generated by the distribution information generating unit 122. Divide biological information. Each divided biological information is temporarily stored in the storage device 11.
4, 420, 430, and 440 exemplify biological information obtained by dividing the biological information 400 according to the distribution information 410. The first biological information 420 is assigned to the storage device 2. The biological information 420 stored in the storage device 2 is data in which the data of the second block, the data of the sixth block,..., The data of the (M−1) th block are connected. The second biological information 430 is assigned to the storage device 3a, and the third biological information 440 is assigned to the storage device 3b.

In step S360, when the user approaches or attaches the IC card 2 to the card reader / writer 13, the communication unit 13 that is the card reader / writer detects this and establishes communication with the IC card 2. When the communication is established, the biometric information registration unit 125 controls the communication unit 13 which is a card reader / writer, and the user ID acquired by the user ID acquisition unit 120 and the distribution information dividing unit 123 1 The IC card 2 stores the first division pattern ID (R1), the first distribution information, and the first partial biometric information divided by the biometric information division unit 124.
Furthermore, the biometric information registering unit 125 controls the communication unit 14 to establish communication with the storage device 3a which is the server a, and the user ID and the divided second divided pattern ID (R2) and divided. The divided second distribution information and the divided second biological information are transmitted to the server a. The server a receives these and stores the second divided pattern ID divided, the second divided distribution information, and the divided second biological information in association with the user ID.
Hereinafter, as in the case of the server a, the user ID, the divided third division pattern ID (T2), the divided third distribution information, and the divided third biological information are the server b. It memorize | stores in the memory | storage device 3b. Similarly, when N is 4 or more, the user ID and the divided fourth to Nth information are sequentially stored in the storage device 3 (not shown).

  In step S370, the control unit 12 deletes and registers information related to the user such as the user ID, face image data, and distribution information temporarily stored in the storage unit 11 so that information is not leaked from the storage unit 11. The process ends.

(Operation at the time of verification in the first embodiment)
The operation of the biometric authentication system of the present invention for collating user biometric information will be described with reference to FIG.
When the user goes to the installation location of the registration / verification terminal 1 and causes the IC card 2 as the storage device 2 to approach or be attached to the communication unit 13 as the card reader / writer, the verification process shown in FIG. 5 is started.

In step S500, the user ID acquisition means 120 acquires the user ID stored in the IC card 2 in the same manner as in step S300 of FIG.
In step S510, the control unit 12 controls the card reader / writer 13 by the registered information reading unit 126 to store the divided first division pattern ID (R1) stored in the IC card 2, and the first divided division ID. Distribution information and the divided first biological information are acquired and temporarily stored in the storage unit 11.
Furthermore, the registration information reading unit 126 transmits the user ID to the storage device 3a that is the server a via the communication unit 14 and the communication network 4. The server a searches and reads out the divided second division pattern ID (R2) corresponding to the received user ID, the divided second distribution information, and the divided second biological information, and registers / Transmit to the verification terminal 1. The control unit 12 receives these and temporarily stores them in the storage unit 11.
The third divided pattern ID (T2) divided in the same manner as in the case of the server a, the third divided distribution information, and the divided third biological information are acquired from the storage device 3b that is the server b. .
When the number of divisions N is 4 or more, the fourth to Nth pieces of divided information are acquired from the storage device 3 (not shown) in the same manner as in the case of the servers a and b.

If registration information is successfully acquired from each storage device (YES in step S520), the process proceeds to step S530. If registration information corresponding to the user ID does not exist in each storage device (NO in step S520), it is determined that the person has not registered and is regarded as a mismatch, and the process proceeds to step S560.
In step S530, when a user who wants to obtain authentication presents a face to the biometric information acquisition unit 10 that is a camera, the camera captures the user and inputs face image data to the control unit 12. Temporarily stores the input face image data in the storage unit 11.

In step S540, the distribution information restoring unit 127 restores the original distribution information. Specifically, the following processing is performed.
(1) The original division pattern ID is restored from the divided division pattern ID read by the registration information reading unit 126.
That is, the exclusive OR of each bit of the divided Nth divided pattern ID and the divided (N-1) th divided pattern ID is calculated, and the calculation result and the (N-2) th divided pattern ID are calculated. The exclusive OR of each bit is calculated, and the exclusive OR of each bit of the first divided pattern ID divided by the calculation result is restored as the divided pattern ID.
In the case of this example, the operation result of the exclusive OR of T2 and R2 and the numerical value 181 that is the exclusive OR of R1 are restored.
(2) A division pattern corresponding to the division pattern ID restored by searching the division pattern table is selected and read.
For example, when the restored division pattern ID is 181, the division pattern 450 in FIG. 4 is selected.
(3) The original distribution information is restored from the divided distribution information read by the registered information reading means 126 according to the selected division pattern.

For example, when the division pattern 450 in FIG. 4 is selected, distribution information 460 from an IC card with a storage device number of 1, distribution information 470 from a server a with a storage device number of 2, and storage device number of 3 is stored. When the distribution information 480 is acquired from a certain server b, the distribution information 410 is restored as follows.
Since the storage device number with the distribution information element number 1 in the division pattern 450 is 1, the first element of the distribution information to be restored is 3 with reference to the distribution information 460, and the distribution information element number 2 in the division pattern 450 Since the storage device number of 1 is 1, the second element of the distribution information to be restored is 1 with reference to the distribution information 460..., And the storage device number of the distribution information element number M is 1 in the division pattern 450. The M-th element of the distribution information restored from is 2 with reference to the distribution information 460.

In step S550, the biometric information restoring unit 128 restores the original biometric information from the divided biometric information acquired by the registered information reading unit 126 according to the distribution information restored by the distribution information restoring unit 127.
For example, the distribution information 410 of FIG. 4 has been restored, the biological information 420 from the IC card with the storage device number 1, the biological information 430 from the server a with the storage device number 2, and the storage device number 3. When the biological information 440 is acquired from a certain server b, the biological information 400 is restored as follows.
Since the storage device number with the block number 1 in the distribution information 410 is 3, the first block of the biometric information to be restored becomes the first block with reference to the biometric information 440, and the block number 2 in the distribution information 410 is stored. Since the device number is 1, the second element of the distribution information to be restored is the second block with reference to the biometric information 420..., And since the storage device number with the block number M in the distribution information 410 is 2 The M-th element of the distribution information is the M-th block with reference to the biological information 430.

  In step S560, the biometric information collating unit 129 collates the face image data acquired from the user for whom the biometric information acquiring unit 10 intends to obtain authentication with the biometric information restored by the biometric information restoring unit 128, and the collation result ( The collation match or collation mismatch) is output to the application system by controlling the communication unit 14, and the user ID and face temporarily stored in the storage unit 11 so as not to leak information from the storage unit 11 in step S570 Information related to the user such as image data, distribution information, and division pattern ID is deleted, and the collation process is terminated.

As described above, the distribution information stored in each storage device and the biological information are not directly related, and it is assumed that the divided distribution information and the divided biological information leak at the same time. However, it is impossible to restore all of the original biological information as well as a part of the original biological information.
Therefore, since the risk due to information leakage is surely reduced, it is possible to reduce the user's psychological resistance to depositing his / her own biological information with another person. The effect of reducing psychological resistance with a sense of security that one's personal information is not completely under the control of another person, especially by making one of the storage devices that store biometric information a portable storage device managed by the user Will rise.

In addition, even a business operator who manages the biometric information of a user does not need to invest excessive security for internal crimes and the management burden is reduced.
Also, since the data size of the divided distribution information is small, the risk of information leakage can be reduced without significantly increasing the communication amount and the storage amount of each storage device as compared with the prior art. This is particularly effective when an IC card having a slow communication and a small storage capacity is used as the storage device 2.

<Second Example>
Next, a biometric authentication system according to the second embodiment of the present invention will be described.
The main difference of the second embodiment from the first embodiment is that the distribution information dividing means 123 divides the distribution information without using the division pattern, and the registration / collation terminal 1 does not require the division pattern table. The memory capacity of the storage unit 11 required for the above is reduced.
Along with the above differences, the processing in some means is different from the first embodiment, but the others are the same as the first embodiment, so a part of the explanation is omitted, and the first embodiment is the same as the first embodiment. Only the differences will be described.

The overall configuration of the biometric authentication system according to the second embodiment is shown in FIG. 1 and is common to the first embodiment.
The configuration of the registration / collation terminal 1 according to the second embodiment is shown in FIG. However, the storage unit 11 does not store the division pattern table. Further, processing by the following means is different from that of the first embodiment.
In the second embodiment, the division number N is 2, the distribution information generation means 122 generates distribution information in which the storage device number is represented by 0 or 1, and the distribution information division means 123 (the division pattern is The distribution information is divided into a random bit string and a bit string that is an exclusive OR of the random bit string, and the biometric information registration unit 125 stores the user ID, the divided distribution information, and the divided biometric information in each storage device. The registration information reading means 126 reads the user ID, the divided distribution information, and the divided biological information from each storage device (does not process the division pattern ID), and restores the distribution information. The means 127 calculates the exclusive OR of the read distribution information to restore the original distribution information.

(Operation at the time of registration in the second embodiment)
The operation of the biometric authentication system according to the second embodiment of the present invention for registering the user's biometric information will be described with reference to FIG.
Note that the operations of steps S300, S310, S320, S350, and S370 are the same as those in the first embodiment, and a description thereof will be omitted.

In step S330, the distribution information generation unit 122 generates and stores distribution information that retains the correspondence between the block and the storage device that stores each block data by generating 0 or 1 bit data randomly M times. This is temporarily stored in the unit 11. The distribution information is an M-digit bit string.
In this example, if the storage device number is 0, it is stored in the storage device 2 that is an IC card, and if the storage device number is 1, it is stored in the storage device 3a that is the server a. .

In step S340, the distribution information dividing unit 123 performs the following processes (1) to (3) to divide the distribution information data generated by the distribution information generating unit 122 into two data, and stores the data in the storage unit 11. Temporarily store.
(1) Bit data of 0 or 1 is randomly generated M times to generate an M-digit bit string X.
(2) The exclusive OR of the distribution information and the bit string X is calculated for each digit. Assume that the M-digit bit string that is the operation result is Y.
(3) If the bit string X matches the distribution information, or if the bit string Y matches the distribution information, the process returns to (1) and is re-divided.
Since the bit string X and the bit string Y are generated based on random numbers, there is no correlation with the distribution information. However, even if both coincide by chance, the correlation is completely eliminated by this processing. This process is particularly effective when the number of blocks M is small.
Thus, the distribution information is divided into M-digit bit strings X and Y. Each of the bit string X and the bit string Y is incomplete, and is complementary data in which the original complete distribution information cannot be restored unless both are prepared. In addition, since neither the contents of the bit string X nor the contents of the bit string Y are related to the contents of the distribution information, it is impossible to restore a part of the biometric information divided from the contents of any bit string.

In step S350, the biological information dividing unit 124 divides each block data divided by the block dividing unit 121 according to the distribution information generated by the distribution information generating unit 122 into two pieces of biological information, and stores the divided biological information. This is temporarily stored in the unit 11.
In step S <b> 360, the biometric information registration unit 125 sends the user ID and the bit string X that is the distribution information divided by the distribution information division unit 123 and the biometric information divided by the biometric information division unit 124 via the communication unit 13. The information is stored in the IC card, and the other of the user ID, the divided distribution information bit string Y, and the divided biological information is stored in the server a via the communication unit 14 and the communication network 4.

(Operation at the time of verification in the second embodiment)
The operation of the biometric authentication system according to the second embodiment of the present invention for collating user biometric information will be described with reference to FIG.
Since the operations of steps S500, S520, S530, S550, S560, and S570 are the same as those in the first embodiment, the description thereof is omitted.

In step S510, the registration information reading unit 126 controls the card reader / writer to acquire the bit string X stored in the IC card and the divided biological information, and temporarily store them in the storage unit 11.
Further, the registration information reading unit 126 controls the communication unit 14 to store the bit string Y stored in correspondence with the user ID acquired by the user ID acquisition unit 120 from the storage device 3a that is the server a and the divided information. The biometric information is read out and temporarily stored in the storage unit 11.
In step S540, the distribution information restoring unit 127 restores the original distribution information. That is, the exclusive OR of the bit string X and the bit string Y is calculated in each digit. The calculation result is the original distribution information.

  In this example, the case where the division number N is 2 has been described. However, even when N is 3 or more, the data can be divided into complementary data of the distribution information. For example, when N = 3, the distribution information dividing unit 123 generates the bit strings X and Y as described above for the binary representation of the distribution information, and then generates a random bit string X1 having the same number of bits as the bit string Y. The distribution information is divided into bit strings Y and X1, Y1 by calculating and calculating the exclusive OR Y1 of the bit string Y and the bit string X1. When N is 4, Y1 may be divided in the same manner.

As described above, the distribution information stored in each storage device and the biometric information cannot even restore a part of the original biometric information, so the risk of information leakage is reliably reduced and the psychology of the user Management burden of a business operator who manages physical resistance and user's biological information is reduced.
Further, since it is not necessary to store the division pattern table, the memory amount required for the registration / verification terminal 1 can be reduced as compared with the first embodiment.

  In the above two embodiments, the case where the facial information is used as the biological information has been described. However, the present invention is also applied to the case where the biological information is a fingerprint, a vein, an iris, a palm, a palm print, a voice, a handwriting, or the like. Is possible.

In the above-described two embodiments, the terminal is described as the registration / collation terminal 1 that performs the registration process and the collation process. However, the functions are separated into a registration terminal that performs only the registration process and a collation terminal that performs only the collation process. In this way, the communication unit 13 of the verification terminal can be realized by a card reader, so that the cost is low. Further, the registration / verification terminal 1, the registration terminal, and the verification terminal may be mixed in the authentication system.
In this case, the registration terminal includes the biometric information acquisition unit 10, the storage unit 11, the control unit 12, the communication unit 13, the communication unit 14, the input unit 15, the user ID acquisition unit 120, and the block division unit 121. The distribution information generating unit 122, the distribution information dividing unit 123, the biometric information dividing unit 124, and the biometric information registering unit 125 are configured to execute the registration process shown in FIG. The collation terminal includes a biometric information acquisition unit 10, a storage unit 11, a control unit 12, a communication unit 13, a communication unit 14, an input unit 15, an ID number acquisition unit 120, a registration information reading unit 126, and a distribution. The information restoring means 127, the biometric information restoring means 128, and the biometric information matching means 129 are configured to execute the matching process shown in FIG.

In the above two embodiments, one of the storage devices has been described as a portable storage device such as an IC card. However, all of the storage devices may be server devices. The communication unit 13 becomes unnecessary, and the registration / verification terminal 1 can be realized at low cost.
In this case, in steps S300 and S500, the user inputs the user ID through the input unit 15, the user ID acquisition unit 120 acquires the user ID from the input unit 15, and the biometric information registration unit 125 in step S360 The divided first biological information or the like is stored in the storage device 3a, the divided second biological information or the like is stored in the storage device 3b, and the biological information reading means 126 is divided in step S510. Are obtained from the storage device 3a, and the second divided biological information is obtained from the storage device 3b.

It is a figure which shows the structure of a biometric authentication system. 2 is a diagram showing a configuration of a registration / verification terminal 1. FIG. It is a figure which shows the flowchart of the operation | movement at the time of registration in a biometrics authentication system. It is a figure which shows the example of the data which a biometrics authentication system produces | generates. It is a figure which shows the flowchart of the operation | movement at the time of collation in a biometrics authentication system.

Explanation of symbols

1 Registration / verification terminal 2 Storage device (IC card)
3a Storage device (server a)
3b storage device (server b)
4 communication network 10 biometric information acquisition unit 11 storage unit 12 control unit 13 communication unit 14 communication unit 15 input unit 120 user ID acquisition unit 121 block division unit 122 distribution information generation unit 123 distribution information division unit 124 biometric information division unit 125 biological Information registration means 126 Registration information reading means 127 Distribution information restoration means 128 Biological information restoration means 129 Biological information collation means 400 Biological information divided into blocks 410 Distribution information 420, 430, 440 Divided biological information 450 Division patterns 460, 470, 480 Divided distribution information

Claims (5)

A biometric authentication system that divides biometric information acquired from a user into a plurality of parts, registers them in separate storage devices according to the distribution information, and restores the biometric information registered according to the distribution information and performs verification. Blocking means for dividing the acquired biometric information into a plurality of block data, distribution information generating means for generating distribution information for determining allocation of the block data to the storage device, and complementary information each of which is incompletely complementary Distribution information dividing means for dividing the data into a predetermined number so as to become data, and storing the block data in the storage device in accordance with the distribution information and storing the complementary data divided by the distribution information dividing means in the predetermined number A biometric authentication system comprising registration means for storing separately in the storage device.
  The biometric authentication system according to claim 1, wherein the distribution information dividing unit divides the distribution information into the complementary data by distributing partial information of the distribution information.   The biometric authentication system according to claim 2, wherein the distribution information dividing unit randomly selects one of a plurality of predetermined division patterns and distributes the partial information according to the selected division pattern.   The distribution information dividing means randomly generates a bit string having the same number of bits as the distribution information as first complementary data, and generates second complementary data as an exclusive OR of the distribution information and the first complementary data. The biometric authentication system according to claim 1 for calculating. The biometric authentication system according to any one of claims 1 to 4, wherein the blocking means divides the block data into smaller block data having a data size that represents a characteristic portion of the biometric information.

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