JP7388417B2 - Information processing method, card, microcontroller and computer program - Google Patents

Description

The present invention relates to an information processing method, a card, a microcontroller , and a computer program in a device with a biometric authentication function.

2. Description of the Related Art Smart cards using biometric information are used to confirm the user's identity using a security IC card for unlocking a door or information, an IC card for payment of a credit card or a prepaid card, and the like. Biometric information includes voice prints and veins, but in the case of cards, fingerprint sensors are often used.

In the above-mentioned fingerprint authentication on an IC card, before issuing the IC card, the issuing company obtains the user's fingerprint data in advance and incorporates a template, which can be obtained when the user uses it. This is done based on a comparison of fingerprint data and a template. In such fingerprint authentication, if the degree of match (similarity) between fingerprint data acquired by a fingerprint sensor and a template is equal to or higher than a threshold value, it is determined that the person is the person in question (Patent Document 1, etc.).

International Publication No. 2018/003689

As described above, fingerprint authentication on an IC card is performed based on comparison with a template. However, human fingerprints are affected by humidity and temperature, and fingerprint sensors are also affected by the environment in which they are used, so the match rate between fingerprint data read by a fingerprint sensor and a fingerprint template is low, even if the fingerprints are the same. Varies depending on usage environment. If the threshold for matching rate is increased to increase security, errors may occur due to changes in the usage environment, even with the fingerprint of the person in question.

An object of the present invention is to provide an information processing method, a card, a microcontroller , and a computer program that can adapt authentication using a fingerprint sensor in a device with biometric authentication to changes in the usage environment.

In the information processing method of the present disclosure, a processing unit built into a card including a non-temporary storage medium and a fingerprint sensor determines the usage environment of the card based on data obtained from a reader/writer of the card, and The threshold values stored in the non-temporary storage medium for each usage environment are read out according to the determined usage environment, and the fingerprint data acquired by the fingerprint sensor and the fingerprint template for comparison stored in the non-temporary storage medium are combined. The user of the card is authenticated by comparing the calculated match rate with the read threshold value.

It is a figure which shows the example of the content of an IC card. FIG. 2 is a block diagram showing the configuration of an IC card. 3 is a flowchart illustrating an example of an authentication processing procedure by a processing unit. FIG. 2 is a block diagram showing the configuration of an IC card in a second embodiment. 7 is a flowchart illustrating an example of an authentication processing procedure by a processing unit according to the second embodiment. 12 is a flowchart illustrating an example of an authentication processing procedure by a processing unit according to a third embodiment.

The present invention will be specifically described with reference to drawings showing embodiments thereof.

(First embodiment)
FIG. 1 is a diagram showing an example of the contents of the IC card 1. As shown in FIG. FIG. 1 shows the front surface of an IC card 1. As shown in FIG. The IC card 1 has a contact plate 11 and a fingerprint sensor 12 exposed. In addition, a hologram, registered name, etc. may be processed on the surface of the IC card 1 for credit card payment. The contact plate 11 is connected inside the IC card 1 to a processing section to be described later, and realizes contact communication with the outside via connection terminals included in the contact plate 11. The fingerprint sensor 12 is a contact sensor about the size of a thumb. The fingerprint sensor 12 is preferably provided at a position where the user naturally places his/her finger when using the IC card 1, in order to read the fingerprint of the finger placed thereon.

FIG. 2 is a block diagram showing the configuration of the IC card 1. As shown in FIG. The IC card 1 includes a processing unit 10, a fingerprint sensor 12, and a contactless I/F 13 including an antenna module for realizing contactless communication.

The processing unit 10 is an MCU (Micro Controller Unit), and includes a processor 100, a ROM (Read Only Memory) 102, a RAM (Random Access Memory) 103, and a memory 104.

Processor 100 executes processing based on computer program 1P stored in ROM 102. The ROM 102 stores a computer program 1P that the processor 100 refers to. The computer program 1P is stored in advance during the manufacturing process of the IC card 1 and the processing section 10. The computer program 1P may be read and stored by the processor 100 from an external storage medium when the ROM 102 has a read mode and a rewrite mode.

RAM 103 is a volatile memory that temporarily stores data generated by processor 100.

Memory 104 is a non-volatile memory (non-temporary storage medium) that stores data referenced by processor 100. Memory 104 is, for example, a flash memory. The memory 104 stores a fingerprint template registered in advance by the user and a threshold value for this fingerprint template when the IC card 1 is manufactured.

In this embodiment, the memory 104 stores threshold values for different usage environments. As will be described later, when the usage environment is identified by "country", threshold values for each country are stored in the memory 104 in association with identification codes that identify the country. The memory 104 may store threshold values for each region (Asia, large states such as America, subdivided regions, etc.). For example, the threshold value in a country (or region) that is drier than the issuing country (or region) of the IC card 1 is set to be equal to or slightly higher than the threshold value in the issuing country (or region). Conversely, the threshold value of a country that is wetter than the issuing country (or region) of the IC card 1 is set and stored as being lower than the threshold value of the issuing country (or region), that is, the standard is set to be looser. The usage environment is not limited to country or region, but may be classified using other data as long as the season and temperature can be inferred.

Processor 100 is connected to contact plate 11 via contact I/F 110. The processor 100 is capable of transmitting and receiving power and communicating with a wired reader/writer that similarly has contact terminals via a plurality of connection terminals included in the contact plate 11 .

Processor 100 is connected to fingerprint sensor 12 via internal I/F 120. The processor 100 can acquire fingerprint data read by the fingerprint sensor 12.

The processor 100 can communicate with a reader/writer via a contactless I/F 13 that includes an antenna module. The non-contact I/F 13 includes an antenna coil (not shown) disposed inside along the edge of the IC card 1 as an antenna module. The processor 100 is activated when the antenna module receives radio waves transmitted from the reader/writer, and the processor 100 is capable of wireless communication with the reader/writer via the non-contact I/F 13.

The fingerprint sensor 12 is a capacitive type sensor that reads the unevenness of a finger and outputs it as two-dimensional data. The fingerprint sensor 12 may also be of an optical type, an ultrasonic type, or the like.

When the IC card 1 configured as described above comes into contact with a wired reader/writer through the contact plate 11, the processing unit 10 and the fingerprint sensor 12 are each supplied with power due to the potential connected to the terminal of the contact plate 11. and execute the process. Similarly, in the IC card 1, when the antenna coil receives radio waves emitted from a wireless reader/writer, the electric power excited by the antenna coil is supplied to the processing unit 10 and the fingerprint sensor 12, and the processing unit 10 and the fingerprint sensor 12 Can perform processing.

In the IC card 1 of this embodiment, the processor 100 of the processing unit 10 uses the fingerprint template stored in the memory 104 to compare the fingerprint data read by the fingerprint sensor 12 with the fingerprint template, and the matching rate is lower than the threshold value. It is determined that the authentication was successful if the value is also high. In the IC card 1 of this embodiment, a plurality of threshold values corresponding to the environment are stored in the memory 104, and a judgment is made using the threshold value corresponding to the usage environment inferred from data obtained from the reader/writer. Enables authentication that adapts to the environment.

FIG. 3 is a flowchart illustrating an example of an authentication processing procedure by the processing unit 10. When the processing unit 10 receives power supply through interaction with the reader/writer, it executes the following authentication process.

When the processor 100 of the processing unit 10 receives a specific command from the reader/writer to start a transaction during data exchange with the reader/writer (step S101), it returns data as a response. (Step S102).

The processor 100 extracts data related to the usage environment included in the specific command received in step S101 (step S103). If it is EMV compliant, for example, a GPO (GET PROCESSING OPTIONS) command may be used as the specific command. The GPO command includes a code (Terminal Country Code) indicating the country of the reader/writer. This allows processor 100 to determine the country in which the payment is to be made.

The processor 100 determines the usage environment from the data regarding the usage environment extracted in step S103 (step S104). In step S104, the processor 100 determines the country, for example.

The processor 100 reads the threshold corresponding to the determined usage environment from the memory 104 (step S105). In step S105, the processor 100 reads, for example, a threshold value corresponding to the determined country and the region in which the country is included. In step S105, if the threshold value corresponding to the determined country does not exist in the memory 104, the processor 100 reads the threshold value set as a default.

The processor 100 receives an authentication request from the reader/writer (step S106), and outputs a fingerprint data acquisition request to the fingerprint sensor 12 in response to the received authentication request (step S107). The processor 100 acquires the fingerprint data responded from the fingerprint sensor 12 (step S108).

The processor 100 compares the fingerprint template stored in the memory 104 with the acquired fingerprint data (step S109), and calculates the matching rate (step S110).

The processor 100 determines whether the match rate is higher than the threshold read in step S105 (step S111), and if it is determined that the match rate is higher than the read threshold (S111: YES), it determines that the authentication is successful. (Step S112). The processor 100 advances the process to step S114.

If it is determined that the match rate is less than or equal to the read threshold (S111: NO), the processor 100 determines that authentication has failed (Step S113), and advances the process to Step S114.

In step S114, the processor 100 outputs the determination result to the reader/writer (step S114), and ends the authentication process.

As mentioned above, even if the fingerprint changes due to humidity or temperature or the fingerprint sensor 12 is affected due to different usage environments, the threshold value corresponding to the usage environment is used to determine the proper authentication. Processing can be carried out.

(Second embodiment)
In the second embodiment, the processing unit 10 performs verification using fingerprint templates of different fingers (for example, thumb and index finger). FIG. 4 is a block diagram showing the configuration of the IC card 1 in the second embodiment. The IC card 1 in the second embodiment has the same configuration as the IC card 1 in the first embodiment except for the details of stored data and processing. Therefore, the same components as those in the first embodiment are given the same reference numerals and detailed explanations will be omitted.

As shown in FIG. 4, in the second embodiment, the memory 104 of the IC card 1 stores a plurality of threshold values for fingerprint templates for each usage environment, corresponding to different fingers registered in advance by the user.

Then, the processor 100 determines whether or not the fingerprint templates of different fingers match each other using a threshold value depending on the usage environment. An example of a processing procedure by the processor 100 will be described below.

FIG. 5 is a flowchart illustrating an example of an authentication processing procedure by the processing unit 10 of the second embodiment. Among the processing procedures shown in the flowchart of FIG. 5, the same steps as those shown in the flowchart of FIG. 3 of the first embodiment are given the same step numbers, and detailed description thereof will be omitted.

After determining the usage environment (S104), the processor 100 of the processing unit 10 reads out threshold values corresponding to the determined usage environment for different fingers (Step S125).

Upon acquiring the fingerprint data (S108), the processor 100 selects a fingerprint template for one finger from among the plurality of fingerprint templates stored in the memory 104 (Step S129). The processor 100 compares the selected fingerprint template with the fingerprint data acquired in step S129 (step S130), and calculates a match rate (step S110).

The processor 100 determines whether the calculated match rate is higher than the threshold read out for the fingerprint template selected in step S129 (step S131). If it is determined that the matching rate is higher than the threshold (S131: YES), the processor 100 determines that the authentication is successful (S112).

In step S131, if the processor 100 determines that the calculated match rate is less than or equal to the read threshold for the selected fingerprint template (S131: NO), the processor 100 determines whether there are any remaining fingerprint templates for other fingers. A judgment is made (step S132). If it is determined that the remaining number remains (S132: YES), the processor 100 returns the process to step S129.

If it is determined that no other fingerprint template remains (S132: NO), the processor 100 determines that authentication has failed (S113), and advances the process to step S114.

In the second embodiment, it is possible to perform fingerprint authentication compatible with different fingers and depending on the usage environment. It becomes possible to carry out appropriate fingerprint authentication according to the usage environment.

(Third embodiment)
In the third embodiment, the threshold value is appropriately adjusted in consideration of other conditions in addition to the usage environment. The IC card 1 in the third embodiment has the same configuration as the IC card 1 in the first embodiment except for details of processing. Therefore, the same components as those in the first embodiment are given the same reference numerals and detailed explanations will be omitted.

In the third embodiment, the memory 104 stores threshold values for different usage environments and required levels of security for fingerprint templates. If the IC card 1 is a credit card, threshold values for each use environment and amount range are stored in the memory 104. If the IC card 1 is a secure device regarding an access key to information, it is preferable that the memory 104 stores threshold values for each usage environment and for each security level of data to be accessed.

Regarding the level of security, the processor 100 may determine that the level of security is high and use it if the issuing country of the IC card 1 is different from the usage environment, that is, the country determined in step S104. Conversely, if the issuing country of the IC card 1 and the usage environment, ie, the country determined in step S104, are the same, the processor 100 may determine that the level of security is low and use the IC card.

FIG. 6 is a flowchart illustrating an example of an authentication processing procedure by the processing unit 10 of the third embodiment. Among the processing procedures shown in the flowchart of FIG. 6, the same steps as those shown in the flowchart of FIG. 3 of the first embodiment are given the same step numbers, and detailed description thereof will be omitted.

In the third embodiment, when the processor 100 determines the usage environment (S104), it acquires data indicating the level of security in authentication from the reader/writer (Step S301). As shown in FIG. 6, the process in step S301 may be performed after determining the usage environment in step S104, or may be performed before the process of receiving a specific command in step S101.

The processor 100 reads out the threshold value corresponding to the data indicating the level of security obtained from the reader/writer in step S301 and the usage environment determined in step S104 (step S302).

The processor 100 then performs a process of comparing the match rate calculated by comparing the fingerprint data that can be obtained from the fingerprint sensor 12 with the stored fingerprint template with the threshold read out in step S302 (S111). ), perform the authentication process.

This makes it possible to perform fingerprint authentication in accordance with the usage environment and the required level of security. It becomes possible to carry out appropriate fingerprint authentication according to the usage environment.

In the first to third embodiments, fingerprint authentication on an IC card has been described as an example. However, the target for updating the fingerprint template is not limited to IC cards. For example, the above threshold adjustment may be applied to unlocking using a fingerprint sensor in, for example, a USB (Universal Serial Bus) device (secure device) that exhibits a locking function for information and communication.

The embodiments disclosed above are illustrative in all respects and are not restrictive. The scope of the present invention is indicated by the claims, and includes all changes within the meaning and range equivalent to the claims.

1 IC card 10 processing unit 100 processor 101 ROM
104 Memory 1P Computer program 12 Fingerprint sensor

Claims (9)

A processing unit built into the card, which includes a non-transitory storage medium and a fingerprint sensor,
determining the usage environment of the card based on data obtained from the reader/writer of the card;
reading the threshold values stored in the non-temporary storage medium for each usage environment according to the determined usage environment;
Calculating a match rate between the fingerprint data acquired by the fingerprint sensor and a fingerprint template for verification stored in the non-temporary storage medium;
An information processing method that authenticates a user of the card by comparing a calculated match rate with a read threshold value. The information processing method according to claim 1, wherein the threshold value is stored in association with data identifying the country or region in which the card is used. The information processing method according to claim 1, wherein the threshold value is stored in association with a country identification code obtained from the reader/writer. The processing unit reads a specific threshold value when the threshold value corresponding to the usage environment determined based on the data obtained from the reader/writer is not stored in the non-temporary storage medium. The information processing method according to any one of the items. The non-temporary storage medium stores threshold values for each usage environment for each of the verification fingerprint templates corresponding to different fingers,
The information processing method according to any one of claims 1 to 4, wherein the processing unit reads threshold values of fingerprint templates of different fingers corresponding to the determined usage environment. The non-temporary storage medium stores threshold values for each level of security and usage environment,
The processing unit includes:
Determining the required level of security based on the data obtained from the reader/writer,
The information processing method according to any one of claims 1 to 5, further comprising reading a threshold value according to the determined level of security and the determined usage environment. a fingerprint sensor that acquires fingerprint data;
a non-temporary storage medium that stores a fingerprint template for comparison with the fingerprint data and a threshold value for each usage environment for the fingerprint template;
a processing unit that executes processing on the fingerprint data and the fingerprint template;
The processing unit includes:
Determining the usage environment of the card based on data obtained from the card reader/writer,
reading a threshold value corresponding to the determined usage environment from the non-temporary storage medium;
Calculating a match rate between the fingerprint data acquired by the fingerprint sensor and a fingerprint template for verification stored in the non-temporary storage medium;
A card that authenticates the user of the card by comparing a calculated match rate with a read threshold. a fingerprint sensor that acquires fingerprint data;
a non-temporary storage medium that stores a fingerprint template for comparison with the fingerprint data and a threshold value for each usage environment for the fingerprint template;
a processing unit that executes processing on the fingerprint data and the fingerprint template;
Equipped with
The processing unit includes:
Determining the usage environment of the card based on data obtained from the card reader/writer,
reading a threshold value corresponding to the determined usage environment from the non-temporary storage medium;
Calculating a match rate between the fingerprint data acquired by the fingerprint sensor and a fingerprint template for verification stored in the non-temporary storage medium;
The user of the card is authenticated by comparing the calculated match rate with the read threshold value.
microcontroller. a computer embedded in the card, including a non-transitory storage medium and a fingerprint sensor;
Determining the usage environment of the card based on data obtained from the card reader/writer ,
reading the threshold values stored in the non-temporary storage medium for each usage environment according to the determined usage environment;
Calculating a match rate between the fingerprint data acquired by the fingerprint sensor and a fingerprint template for verification stored in the non-temporary storage medium;
A computer program that executes a process of authenticating a user of the card by comparing the calculated match rate with a read threshold value.

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