KR102671054B1 - Method and system for payment for central bank digital currency - Google Patents

Abstract

It provides a payment method and system that can process payments using Central Bank Digital Currency (CBDC) without double payments even in offline situations (situations where the user's terminal cannot connect to the server through the network).

Description

Payment method and system for central bank digital currency {METHOD AND SYSTEM FOR PAYMENT FOR CENTRAL BANK DIGITAL CURRENCY}

The explanation below relates to payment methods and systems for central bank digital currency.

Central Bank Digital Currency (CBDC) is an electronic form of currency issued by the central bank. CBDC implementation method is a single ledger method (account method) in which the central bank or banks store and manage CBDC accounts and related transaction information. ) and distributed ledger methods in which multiple transaction participants manage the same transaction records.

[Prior document number]

Korean Patent No. 10-1862637

It provides a payment method and system that can process payments using Central Bank Digital Currency (CBDC) without double payments even in offline situations (situations where the user's terminal cannot connect to the server through the network).

In the payment method of a computer device, the computer device includes a security area, a hardware security module (HSM), and at least one processor, and the payment method is performed by the at least one processor through short-distance communication in an offline situation. Receiving a nonce value from the terminal of the end user who will receive the remittance; By the at least one processor, a remittance transaction including the first last transaction information stored in the secure area, the received nonce value, and a hash value of the security value is signed using the secret key of the HSM and transmitted to the terminal. steps; transmitting, by the at least one processor, the original text of the security value to the terminal when a verification success message is received from the terminal; and storing, by the at least one processor, the second last transaction information according to the remittance transaction and the latest balance of the electronic wallet in the secure area.

According to one side, the security area may be characterized as including a Trusted Execution Environment (TEE) security area or a White-Box Cryptographic (WBC) security area.

According to another aspect, in response to the offline situation changing to an online situation, the terminal transmits the original text of the remittance transaction and the security value to the CBDC ledger, thereby synchronizing the transaction that occurred in the offline situation.

According to another aspect, the payment method may further include the step of authenticating the terminal by exchanging a certificate with the terminal by the at least one processor.

According to another aspect, the certificate is issued to include device-specific information of the device to which the certificate was issued, public information of the HSM included in the device, issuing authority information, and expiration date, and is stored in a security area included in the device. It can be characterized as being.

According to another aspect, signature verification of the remittance transaction may be processed in the terminal using public information of the HSM included in the certificate of the computer device.

According to another aspect, the step of signing the remittance transaction using the secret key of the HSM and transmitting it to the terminal further transmits the public information of the HSM to the terminal, and transmits the public information of the HSM to the terminal. It may be characterized in that the signature verification of the remittance transaction is processed using the method.

In the payment method of a computer device, the computer device includes a first security area, a Hardware Security Module (HSM), and at least one processor, and the payment method includes short-distance communication in an offline situation by the at least one processor. A step of transmitting a nonce value to the terminal of an end user making a remittance through; Receiving, by the at least one processor, from the terminal a remittance transaction signed using a secret key of the HSM of the terminal, the remittance transaction comprising: first last transaction information stored in a second secure area of the terminal; Contains the hash value of the delivered nonce value and security value -; signature verifying, by the at least one processor, the received money transfer transaction; verifying, by the at least one processor, a nonce value included in the received remittance transaction; transmitting a verification success message to the terminal when verification of the signature and verification of the nonce value are successful by the at least one processor; storing, by the at least one processor, the received money transfer transaction and a second last transaction in the first secure area; and receiving, by the at least one processor, the original text of the security value transmitted in response to receiving the verification success message from the terminal.

According to one side, each of the first security area and the second security area may include a Trusted Execution Environment (TEE) security area or a White-Box Cryptographic (WBC) security area.

According to another aspect, in order to synchronize a transaction that occurred in the offline situation in response to the offline situation changing to an online situation, the payment method may include the remittance transaction stored in the first secure area by the at least one processor. And it may further include the step of transmitting the original text of the security value to the CBDC ledger.

According to another aspect, the payment method may further include authenticating the terminal by exchanging a certificate with the terminal by the at least one processor.

According to another aspect, the certificate is issued to include device-specific information of the device to which the certificate was issued, public information of the HSM included in the device, issuing authority information, and expiration date, and is stored in a security area included in the device. It can be characterized as being.

According to another aspect, the step of verifying the signature may be characterized by verifying the signature of the remittance transaction using public information of the HSM included in the terminal, the issuing agency information, and the expiration date.

According to another aspect, the step of receiving the signed remittance transaction further includes receiving public information of the HSM included in the terminal from the terminal, and the step of verifying the signature uses the public information of the received HSM. Thus, the remittance transaction may be characterized by signature verification.

A computer program stored on a computer-readable recording medium is provided in conjunction with a computer device to execute the method on the computer device.

Provided is a computer-readable recording medium on which a program for executing the above method on a computer device is recorded.

At least one processor configured to execute computer-readable instructions; security area; and a Hardware Security Module (HSM), wherein a nonce value is received from the terminal of an end user who will receive the remittance through short-distance communication in an offline situation, by the at least one processor, and first and last transaction information stored in the security area. , the remittance transaction including the received nonce value and the hash value of the security value is signed using the secret key of the HSM and transmitted to the terminal, and when a verification success message is received from the terminal, the original text of the security value transmits to the terminal, and stores the second last transaction information according to the remittance transaction and the latest balance of the electronic wallet in the secure area.

At least one processor configured to execute computer-readable instructions; first security zone; and an HSM (Hardware Security Module), wherein a nonce value is transmitted by the at least one processor to the terminal of an end user making a remittance through short-distance communication in an offline situation, and a secret key of the HSM of the terminal is received from the terminal. Receive a signed remittance transaction using, - the remittance transaction includes a hash value of the first last transaction information, the transmitted nonce value, and the security value stored in the second security area of the terminal; Signature verifies the received remittance transaction, verifies the nonce value included in the received remittance transaction, and if the signature verification and verification of the nonce value are successful, transmits a verification success message to the terminal, and the reception A computer device is provided, wherein the remittance transaction and the second last transaction are stored in the first security area, and the terminal receives the original text of the security value transmitted in response to receiving the verification success message.

Even in offline situations (where the user's terminal cannot connect to the server through the network), payments can be processed using Central Bank Digital Currency (CBDC) without double payments.

1 is a diagram illustrating an example of a network environment according to an embodiment of the present invention.
Figure 2 is a block diagram showing an example of a computer device according to an embodiment of the present invention.
Figure 3 is a diagram showing an example of the internal configuration of an end-user terminal according to an embodiment of the present invention.
Figure 4 is a flowchart showing an example of an online payment method according to an embodiment of the present invention.
Figure 5 is a flowchart showing an example of an offline payment method according to an embodiment of the present invention.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings.

The payment system according to embodiments of the present invention may be implemented by at least one computer device. At this time, the computer program according to an embodiment of the present invention may be installed and driven in the computer device, and the computer device may perform the payment method according to the embodiments of the present invention under the control of the driven computer program. The above-described computer program can be combined with a computer device and stored in a computer-readable recording medium to execute a payment method on the computer.

1 is a diagram illustrating an example of a network environment according to an embodiment of the present invention. The network environment in FIG. 1 shows an example including a plurality of electronic devices 110, 120, 130, and 140, a plurality of servers 150 and 160, and a network 170. Figure 1 is an example for explaining the invention, and the number of electronic devices or servers is not limited as in Figure 1. In addition, the network environment in FIG. 1 only explains one example of environments applicable to the present embodiments, and the environment applicable to the present embodiments is not limited to the network environment in FIG. 1.

The plurality of electronic devices 110, 120, 130, and 140 may be fixed terminals or mobile terminals implemented as computer devices. Examples of the plurality of electronic devices 110, 120, 130, and 140 include smart phones, mobile phones, navigation devices, computers, laptops, digital broadcasting terminals, PDAs (Personal Digital Assistants), and PMPs (Portable Multimedia Players). ), tablet PC, etc. For example, in FIG. 1, the shape of a smartphone is shown as an example of the electronic device 110. However, in embodiments of the present invention, the electronic device 110 actually communicates with other devices through the network 170 using a wireless or wired communication method. It may refer to one of various physical computer devices capable of communicating with electronic devices 120, 130, 140 and/or servers 150, 160.

The communication method is not limited, and may include not only a communication method utilizing a communication network that the network 170 may include (for example, a mobile communication network, wired Internet, wireless Internet, and a broadcast network), but also short-range wireless communication between devices. For example, the network 170 may include a personal area network (PAN), a local area network (LAN), a campus area network (CAN), a metropolitan area network (MAN), a wide area network (WAN), and a broadband network (BBN). , may include one or more arbitrary networks such as the Internet. Additionally, the network 170 may include any one or more of network topologies including a bus network, star network, ring network, mesh network, star-bus network, tree or hierarchical network, etc. Not limited.

Each of the servers 150 and 160 is a computer device or a plurality of computers that communicate with a plurality of electronic devices 110, 120, 130, 140 and a network 170 to provide commands, codes, files, content, services, etc. It can be implemented with devices. For example, the server 150 provides services (e.g., payment service, virtual exchange service, risk monitoring service, instant messaging) to a plurality of electronic devices 110, 120, 130, and 140 connected through the network 170. It may be a system that provides services, game services, group call services (or voice conference services), messaging services, mail services, social network services, map services, translation services, financial services, search services, content provision services, etc.).

Figure 2 is a block diagram showing an example of a computer device according to an embodiment of the present invention. Each of the plurality of electronic devices 110, 120, 130, and 140 described above or each of the servers 150 and 160 may be implemented by the computer device 200 shown in FIG. 2.

As shown in FIG. 2, this computer device 200 may include a memory 210, a processor 220, a communication interface 230, and an input/output interface 240. The memory 210 is a computer-readable recording medium and may include a non-permanent mass storage device such as random access memory (RAM), read only memory (ROM), and a disk drive. Here, non-perishable large-capacity recording devices such as ROM and disk drives may be included in the computer device 200 as a separate permanent storage device that is distinct from the memory 210. Additionally, an operating system and at least one program code may be stored in the memory 210. These software components may be loaded into the memory 210 from a computer-readable recording medium separate from the memory 210. Such separate computer-readable recording media may include computer-readable recording media such as floppy drives, disks, tapes, DVD/CD-ROM drives, and memory cards. In another embodiment, software components may be loaded into the memory 210 through the communication interface 230 rather than a computer-readable recording medium. For example, software components may be loaded into memory 210 of computer device 200 based on computer programs installed by files received over network 170.

The processor 220 may be configured to process instructions of a computer program by performing basic arithmetic, logic, and input/output operations. Commands may be provided to the processor 220 by the memory 210 or the communication interface 230. For example, processor 220 may be configured to execute received instructions according to program code stored in a recording device such as memory 210.

The communication interface 230 may provide a function for the computer device 200 to communicate with other devices (eg, the storage devices described above) through the network 170. For example, a request, command, data, file, etc. generated by the processor 220 of the computer device 200 according to a program code stored in a recording device such as memory 210 is transmitted to the network ( 170) and can be transmitted to other devices. Conversely, signals, commands, data, files, etc. from other devices may be received by the computer device 200 through the communication interface 230 of the computer device 200 via the network 170. Signals, commands, data, etc. received through the communication interface 230 may be transmitted to the processor 220 or memory 210, and files, etc. may be stored in a storage medium (as described above) that the computer device 200 may further include. It can be stored as a permanent storage device).

The input/output interface 240 may be a means for interfacing with the input/output device 250. For example, input devices may include devices such as a microphone, keyboard, or mouse, and output devices may include devices such as displays and speakers. As another example, the input/output interface 240 may be a means for interfacing with a device that integrates input and output functions, such as a touch screen. At least one of the input/output devices 250 may be configured as one device with the computer device 200. For example, like a smart phone, a touch screen, microphone, speaker, etc. may be included in the computer device 200.

Additionally, in other embodiments, computer device 200 may include fewer or more components than those of FIG. 2 . However, there is no need to clearly show most prior art components. For example, the computer device 200 may be implemented to include at least some of the input/output devices 250 described above, or may further include other components such as a transceiver, a database, etc.

In order to process payments using Central Bank Digital Currency (CBDC), the end-user terminal must frequently communicate with the server to update ledger information. Meanwhile, payments between end users must be made even in offline situations, such as situations where the end user terminal cannot connect to the network. At this time, double payments should not occur and end users should be able to be authenticated.

Figure 3 is a diagram showing an example of the internal configuration of an end-user terminal according to an embodiment of the present invention. The first end-user terminal 310 and the second end-user terminal 320 according to this embodiment can process payments while communicating with the server 330, but in an offline situation, the end-user terminals (the first end-user terminal) Offline payments between end-user terminals can be processed through communication between (310) and the second end-user terminal (320). Afterwards, when communication with the server 330 becomes possible, end-user terminals can synchronize the contents of the offline payment with the server 330 through communication with the server 330. The server 330 may be a server device of a service provider that processes payments using CBDC between the CBDC platform and end-user terminals. Hereinafter, the term “server” used without particular limitation in this specification may mean a server of a service provider.

To prevent double payment during offline payments, the first end-user terminal 310 is equipped with a P2P communication module 311, a Hardware Security Module (HSM) 312, and a Trusted Execution Environment (TEE) security system as shown in FIG. 3. It may include area 313. The second end-user terminal 320 may also have the same or similar internal configuration as the first end-user terminal 310. The first end-user terminal 310 and the second end-user terminal 320 may be implemented by the computer device 200 described with reference to FIG. 2, and are not essential for offline payment in the embodiment of FIG. 3. Elements have been omitted.

The P2P communication module 311 may include a communication module for short-distance communication, such as Bluetooth or NFC (Near Field Communication). In order for payments to be made between end users even in situations where users cannot communicate with the server through the network (e.g., offline situations such as temporary network failures or disasters), at least the end users' terminals (e.g. Since communication between the first end user terminal 310 and the second end user terminal 320 of FIG. 3 must be possible, the P2P communication module 311 may be required.

The HSM 312 may include a module for managing and protecting private keys that cannot be physically copied or extracted. In general, instead of using the method of using a secret key such as an encryption key in the encryption API by loading it in memory, etc., the HSM 312 can utilize a method of sending the data inside the HSM 312 and receiving the result when encrypting and decrypting the data. there is. Therefore, since the secret key is managed internally and is not leaked to the outside, and the cryptographic operation itself can be performed inside the HSM 312, leakage of the secret key can be fundamentally prevented. For example, the computer device 200 of FIG. 2 may further include a physical device for the HSM 312.

The TEE security area 313 can provide security functions such as application integrity and data confidentiality in a safe execution environment by providing an independent hardware security area. For example, the processor 220 included in the computer device 200 of FIG. 2 may include a TEE function for providing the TEE security area 313.

Additionally, depending on the embodiment, the TEE security area 313 configured in hardware may be replaced with software technology. For example, WBC (White-Box Cryptographic) is a software technology that can safely store data and prevent the stored data from being revealed even if the encryption algorithm is executed on an untrusted terminal.

It will be easy to understand that the TEE-based security area described later can be expanded to a “security area” that includes either a hardware security area or a software security area.

Since Bluetooth, NFC for short-distance communication, HSM, and TEE for security are already well known, detailed explanations will be omitted.

In order to process payment in an offline situation, it is assumed that the conditions (1) to (5) below are satisfied in the payment method according to the present embodiments.

(1) Each of the end-user terminals (eg, each of the first end-user terminal 310 and the second end-user terminal 320) may be an HSM device with a unique secret key. In other words, two or more end-user terminals do not have the same secret key.

(2) The latest information signed in the end-user terminal is recorded in the TEE, and each time a signature is signed, the signature can be processed using the information recorded in the TEE. For example, the latest information signed by the first end-user terminal 310 may be recorded in the TEE secure area 313, and the first end-user terminal 310 may record the signed information recorded in the TEE secure area 313. The next signature can be processed using the latest information.

(3) Information about the final balance synchronized with the server is recorded in TEE. For example, the first end-user terminal 310 may record information about the final balance synchronized through communication with the server in the TEE security area 313.

(4) Allows the electronic wallet of users who have completed KYC (Know Your Customer) authentication to be used. Depending on the embodiment, KYC authentication may be optionally processed so that foreigners can also use it. If an electronic wallet without KYC authentication is allowed to be used, restrictions such as limiting the upper limit of the amount that can be paid can be set to apply to the electronic wallet.

(5) A PKI-based certificate is issued by a CA (Certification Authority) to the only device that will use the HSM. At this time, the certificate is not issued twice, and the certificate can be stored in the TEE (for example, the TEE security area 313). Certificate information may include device-specific information, HSM public information, issuing authority information, and expiration date. For example, device-specific information may include information that can uniquely identify the end-user terminal, and public information may include information (e.g., public key) that is disclosed in response to the secret key stored in the HSM. .

Previously, in the embodiment of FIG. 3, an embodiment was described in which the first end-user terminal 310 includes all the P2P communication module 311, HSM 312, and TEE security area 313, but the device supporting TEE ( For example, a combination of a smart phone) and a smart HSM (for example, ledger Nano, Trezor, YubiKey, etc.) or a device that supports a network (for example, a POS (Point Of Sales) or smartphone, etc.) with a TEE and HSM. It may also be implemented in a combined form with a device equipped with (for example, an HSM card with secure storage).

In the case of smartphones, portable chargers or equipment that can be charged with batteries can be purchased at a low price, making it easy to prepare for power outages. In addition, even in the case of separately developed end-user terminals, it is possible to prepare for powerlessness by having a built-in battery that can be recharged via micro-USB or USB-C so that it can be charged with a portable charging device or batteries. In addition, if the end-user terminal is developed as a small card-type device, the battery can be replaced and a design that can be used for a long time with low power is required.

On the other hand, when issuing an end-user terminal (e.g., the first end-user terminal 310 or the second end-user terminal 320), or when setting up the use of an end-user terminal, an intermediary (e.g., a central Authentication processes such as KYC authentication and/or ID/password authentication can be performed by financial institutions other than banks).

Additionally, a certificate may be issued to an end-user terminal for which authentication has been completed. As already explained, the certificate may include signed device-specific information, HSM public information, issuing authority information, and expiration date. The expiration date can be used to ensure that the certificate is reissued periodically to maintain the latest information.

Additionally, when a user uses an end-user terminal, device user authentication may be processed through a password or biometric authentication such as fingerprint, iris, or facial recognition. For example, a payment program installed and running on an end-user terminal controls the end-user terminal to first authenticate the user by performing device user authentication when the user wants to make a payment using the end-user terminal. You can.

When authenticating between users when connecting online or offline, the information used when authenticating from the CA, such as the certificate, device unique information, public information of the HSM, issuing authority information, and expiration date, is shared with the server or other users. It may be transmitted to the end-user terminal to authenticate the user's end-user terminal.

Figure 4 is a flowchart showing an example of an online payment method according to an embodiment of the present invention. The online payment method according to this embodiment may be performed by the computer device 200 implementing an end-user terminal. At this time, the processor 220 of the computer device 200 may be implemented to execute control instructions according to the code of an operating system included in the memory 210 or the code of at least one computer program. Here, the processor 220 causes the computer device 200 to perform steps 410 to 470 included in the method of FIG. 4 according to control instructions provided by code stored in the computer device 200. can be controlled.

In step 410, when the computer device 200 is authenticated by a CA, such as a certificate issued to the computer device 200, device-specific information of the computer device 200, public information of the HSM, and issuing authority information and expiration date, etc. The information used may be transmitted to the service provider's server. In this case, the service provider's server uses the information used when authenticating from the CA, such as the transmitted certificate, device unique information, public information of the HSM, issuing authority information, expiration date, etc., to connect the computer device 200 as an end-user terminal. can be authenticated.

In step 420, the computer device 200 may inquire the latest balance and last transaction information (sequence number) of the user's electronic wallet through the server.

In step 430, the computer device 200 may store the latest balance and last transaction information in the TEE. As already explained, the TEE-based security area, which is composed of hardware, may be replaced by software technology such as WBC.

In step 440, the computer device 200 may receive remittance information. For example, the computer device 200 may receive input of the remittance amount and recipient information from the user.

In step 450, the computer device 200 may sign the last transaction information and remittance information using the HSM. For example, the last transaction information and remittance information can be signed using the secret key contained in the HSM.

In step 460, the computer device 200 may transmit the signed information to the server. The server can process the payment by delivering the remittance amount to the recipient's electronic wallet according to the transmitted information and deducting the remittance amount from the user's electronic wallet.

In step 470, the computer device 200 may check the processing result. At this time, when processing is completed, the computer device 200 may store the latest balance and last transaction information of the electronic wallet in the TEE.

Figure 5 is a flowchart showing an example of an offline payment method according to an embodiment of the present invention. In this embodiment, when communication with the service user's server is impossible, end-user terminal a (510) of end-user A, which sends the money, and end-user terminal b (520) of end-user B, who receives the money, use P2P using a local network. An example of payment processing through communication (hereinafter referred to as short-distance communication) will be described. First, end-user terminal a (510) and end-user terminal b (520) exchange certificates through short-distance communication to confirm that they are each other's authenticated devices. Each of these end user terminals a (510) and end user terminals (b) 520 may be implemented by the computer device 200, and may each include a TEE security area and an HSM.

In step 531, end-user terminal b (520) may transmit a nonce value for a transaction to end-user terminal a (510). The nonce value may be a randomly generated value.

In step 532, end-user terminal a (510) may transmit a remittance transaction including the last transaction information 1, a nonce value, and a hash value of a specific security value to end-user terminal b (520). Here, the last transaction information 1 may include a sequence number stored in the TEE, and the specific security value may be a randomly generated value. At this time, the remittance transaction may be signed with the HSM's private key and transmitted to the end user terminal b (520) along with the public key as public information of the HSM. According to the embodiment, end-user terminal a (510) does not need to transmit the public key as public information of the HSM to end-user terminal b (520), and end-user terminal b (520) receives the certificate from end-user terminal a (510). You can also obtain the public key as public information of the HSM.

In step 533, end-user terminal b (520) can verify the received remittance transaction and nonce value. As an example, end-user terminal b (520) can process signature verification for a received remittance transaction using a public key and check whether the nonce value included in the remittance transaction is the same as the nonce value delivered in step 510. You can. At this time, if the signature verification for the received remittance transaction fails, the received nonce value is different from the nonce value delivered in step 510, or an already processed nonce value is received, the end user terminal b 520 A failure message can be transmitted to user terminal a (510). Additionally, end-user terminal b (520) may store the received remittance transaction together with the last transaction information 2. Here, last transaction information 2, unlike last transaction information 1, may be information about the current transaction.

In step 534, end-user terminal b (520) may transmit the verification result to end-user terminal a (510). For example, end-user terminal b (520) may transmit a verification success message or a verification failure message to end-user terminal a (510).

In step 535, if the verification result is successful, end-user terminal a (510) may transmit the original text of the security value of the remittance transaction to end-user terminal b (520). If end-user terminal b (520) does not receive a verification success message from end-user terminal b (520) within a certain period of time, the transaction may be cancelled. In this case, end-user terminal b (520) cannot receive the original text of the security value.

In step 536, end user terminal a (510) may store the last transaction information 2 and the latest balance in the TEE. The latest balance may be the latest balance of end-user A's electronic wallet.

After communication is restored, end-user terminal b (520) transmits the original text of the remittance transaction and security value received from end-user terminal a (510) to the CBDC ledger, and sends it from end-user terminal a (510) to end-user terminal b ( 520) Transactions that occurred offline can be synchronized with the ledger in order. If the end-user terminal b (520) does not receive the original text of the security value in step 550, synchronization with the ledger may fail, and the transaction may be substantially cancelled. Since the last transaction information must be updated through this transaction, the last transaction information 2, unlike the last transaction information 1, may be information about the current transaction. Depending on the embodiment, the last transaction information 2 stored in the TEE of end-user terminal a (510) in step 536 and the last transaction information 2 stored in the TEE of end-user terminal b (520) in step 533 are at least partially The contents of may be different information.

Depending on the embodiment, the following restrictions (a) to (c) may be applied.

(a) Transaction amounts received in an offline situation cannot be used online without synchronization with the CBDC ledger service.

(b) The amount available on the end user terminal may be limited.

(c) You can set at least one of the limits of the amount that can be used offline, the number of transactions, and the effective time for transactions in offline situations, and restrict transactions if the limit, number, or time is exceeded.

According to this embodiment, all transactions of an electronic wallet linked to an HSM are processed in an end-user terminal including the corresponding HSM. For example, because the HSM's private key cannot be copied, it can be guaranteed that all transactions in a linked electronic wallet are processed on the end-user terminal containing the HSM. In addition, it cannot be used on other devices because it verifies whether the device-specific information recorded in the certificate and the public information of the HSM are the same through authentication of the electronic wallet. Additionally, according to this embodiment, completed transactions cannot be forcibly modified because they are stored in the TEE. At this time, since the transaction is carried out only in one end-user terminal, the information stored in the TEE is always up-to-date. Therefore, double spending can be prevented.

Additionally, in this embodiment, a TEE-based security area configured in hardware is described, but this TEE may be replaced by software technology such as WBC.

As such, according to embodiments of the present invention, payments are processed using Central Bank Digital Currency (CBDC) without double payment even in offline situations (situations where the user's terminal cannot connect to the server through the network). can do.

The system or device described above may be implemented with hardware components or a combination of hardware components and software components. For example, devices and components described in embodiments may include, for example, a processor, a controller, an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a field programmable gate array (FPGA), etc. , may be implemented using one or more general-purpose or special-purpose computers, such as a programmable logic unit (PLU), a microprocessor, or any other device capable of executing and responding to instructions. The processing device may execute an operating system (OS) and one or more software applications running on the operating system. Additionally, a processing device may access, store, manipulate, process, and generate data in response to the execution of software. For ease of understanding, a single processing device may be described as being used; however, those skilled in the art will understand that a processing device includes multiple processing elements and/or multiple types of processing elements. It can be seen that it may include. For example, a processing device may include a plurality of processors or one processor and one controller. Additionally, other processing configurations, such as parallel processors, are possible.

Software may include a computer program, code, instructions, or a combination of one or more of these, which may configure a processing unit to operate as desired, or may be processed independently or collectively. You can command the device. Software and/or data may be used on any type of machine, component, physical device, virtual equipment, computer storage medium or device to be interpreted by or to provide instructions or data to a processing device. It can be embodied in . Software may be distributed over networked computer systems and stored or executed in a distributed manner. Software and data may be stored on one or more computer-readable recording media.

The method according to the embodiment may be implemented in the form of program instructions that can be executed through various computer means and recorded on a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, etc., singly or in combination. The medium may continuously store a computer-executable program, or may temporarily store it for execution or download. In addition, the medium may be a variety of recording or storage means in the form of a single or several pieces of hardware combined. It is not limited to a medium directly connected to a computer system and may be distributed over a network. Examples of media include magnetic media such as hard disks, floppy disks, and magnetic tapes, optical recording media such as CD-ROMs and DVDs, magneto-optical media such as floptical disks, And there may be something configured to store program instructions, including ROM, RAM, flash memory, etc. Additionally, examples of other media include recording or storage media managed by app stores that distribute applications, sites or servers that supply or distribute various other software, etc. Examples of program instructions include machine language code, such as that produced by a compiler, as well as high-level language code that can be executed by a computer using an interpreter, etc.

As described above, although the embodiments have been described with limited examples and drawings, various modifications and variations can be made by those skilled in the art from the above description. For example, the described techniques are performed in a different order than the described method, and/or components of the described system, structure, device, circuit, etc. are combined or combined in a different form than the described method, or other components are used. Alternatively, appropriate results may be achieved even if substituted or substituted by an equivalent.

Therefore, other implementations, other embodiments and equivalents of the claims also fall within the scope of the following claims.

Claims (20)

In the payment method for computer devices,
The computer device includes a security zone, a Hardware Security Module (HSM), and at least one processor,
The above payment method is,
Receiving, by the at least one processor, a nonce value from a terminal of an end user who is to receive a remittance through short-distance communication in an offline situation;
By the at least one processor, a remittance transaction including the first last transaction information stored in the secure area, the received nonce value, and a hash value of the security value is signed using the secret key of the HSM and transmitted to the terminal. steps;
transmitting, by the at least one processor, the original text of the security value to the terminal when a verification success message is received from the terminal; and
storing, by the at least one processor, a second last transaction information according to the remittance transaction and the latest balance of the electronic wallet in the secure area.
Including,
A payment method, wherein the security area includes a Trusted Execution Environment (TEE) security area or a White-Box Cryptographic (WBC) security area. delete According to paragraph 1,
A payment method characterized in that transactions occurring in the offline situation are synchronized by transmitting the original text of the remittance transaction and the security value from the terminal to the CBDC ledger in response to the change from the offline situation to the online situation. According to paragraph 1,
The above payment method is,
Authenticating the terminal by exchanging a certificate with the terminal, by the at least one processor
A payment method further comprising: According to clause 4,
The certificate is issued to include device-specific information of the device to which the certificate was issued, public information of the HSM included in the device, issuing authority information, and expiration date, and is stored in a security area included in the device.
A payment method characterized by . According to clause 5,
In the terminal, signature verification of the remittance transaction is processed using the public information of the HSM included in the certificate of the computer device.
A payment method characterized by . According to paragraph 1,
The step of signing the remittance transaction using the secret key of the HSM and transmitting it to the terminal,
Further transmitting the public information of the HSM to the terminal,
Signature verification of the remittance transaction is processed in the terminal using the public information of the HSM.
A payment method characterized by . In the payment method for computer devices,
The computer device includes a first security zone, a Hardware Security Module (HSM), and at least one processor,
The above payment method is,
transmitting, by the at least one processor, a nonce value to a terminal of an end user making a remittance through short-distance communication in an offline situation;
Receiving, by the at least one processor, from the terminal a remittance transaction signed using a secret key of the HSM of the terminal, the remittance transaction comprising: first last transaction information stored in a second secure area of the terminal; Contains the hash value of the delivered nonce value and security value -;
signature verifying, by the at least one processor, the received money transfer transaction;
verifying, by the at least one processor, a nonce value included in the received remittance transaction;
transmitting a verification success message to the terminal when verification of the signature and verification of the nonce value are successful by the at least one processor;
storing, by the at least one processor, the received money transfer transaction and a second last transaction in the first secure area; and
Receiving, by the at least one processor, the original text of the security value transmitted in response to receiving the verification success message from the terminal.
Including,
A payment method, characterized in that each of the first security area and the second security area includes a Trusted Execution Environment (TEE) security area or a White-Box Cryptographic (WBC) security area. delete According to clause 8,
In order to synchronize transactions that occurred in the offline situation in response to the offline situation changing to an online situation, the payment method:
Transmitting, by the at least one processor, the original text of the remittance transaction and the security value stored in the first security area to the CBDC ledger.
A payment method further comprising: According to clause 8,
The above payment method is,
Authenticating the terminal by exchanging a certificate with the terminal, by the at least one processor
A payment method further comprising: According to clause 11,
The certificate is issued to include device-specific information of the device to which the certificate was issued, public information of the HSM included in the device, issuing authority information, and expiration date, and is stored in a security area included in the device.
A payment method characterized by . According to clause 12,
The signature verification step is,
Signature verification of the remittance transaction using the public information of the HSM included in the terminal, the issuing organization information, and the expiration date
A payment method characterized by . According to clause 8,
The step of receiving the signed remittance transaction is:
Further receiving public information of the HSM included in the terminal from the terminal,
The signature verification step is,
Signature verification of the remittance transaction using the public information of the received HSM
A payment method characterized by . A computer program stored in a computer-readable recording medium in combination with a computer device to execute the method of any one of claims 1, 3 to 8, or 10 to 14 on the computer device. A computer-readable recording medium recording a computer program for executing the method of any one of claims 1, 3 to 8, or 10 to 14 on a computer device. At least one processor implemented to execute readable instructions on a computer device;
security area; and
Hardware Security Module (HSM)
Including,
By the at least one processor,
In an offline situation, a nonce value is received from the terminal of the end user who will receive the remittance through short-distance communication,
Signing a remittance transaction including the first last transaction information stored in the secure area, the received nonce value, and a hash value of the security value using the secret key of the HSM and transmitting it to the terminal,
When receiving a verification success message from the terminal, transmit the original text of the security value to the terminal,
Store the second last transaction information according to the remittance transaction and the latest balance of the electronic wallet in the secure area,
The security area includes a Trusted Execution Environment (TEE) security area or a White-Box Cryptographic (WBC) security area.
A computer device characterized by a. According to clause 17,
In response to the offline situation changing to an online situation, the transaction that occurred in the offline situation is synchronized by transmitting the original text of the remittance transaction and the security value from the terminal to the CBDC ledger.
A computer device characterized by a. At least one processor configured to execute computer-readable instructions;
first security zone; and
Hardware Security Module (HSM)
Including,
By the at least one processor,
In an offline situation, the nonce value is transmitted to the terminal of the end user making the transfer through short-distance communication,
Receive a remittance transaction signed using the secret key of the HSM of the terminal from the terminal, - the remittance transaction includes a hash of the first last transaction information stored in the second security area of the terminal, the transmitted nonce value, and the security value Contains value -;
Verify the signature of the received remittance transaction,
Verify the nonce value included in the received remittance transaction,
If the signature verification and the verification of the nonce value are successful, sending a verification success message to the terminal,
storing the received remittance transaction and the second last transaction in the first secure area;
Receiving the original text of the security value transmitted in response to receiving the verification success message from the terminal,
Each of the first security area and the second security area includes a Trusted Execution Environment (TEE) security area or a White-Box Cryptographic (WBC) security area.
A computer device characterized by a. According to clause 19,
By the at least one processor,
To synchronize transactions that occurred in the offline situation in response to the offline situation changing to an online situation,
Transmitting the original text of the remittance transaction and the security value stored in the first security area to the CBDC ledger
A computer device characterized by a.

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