WO2017162164A1

WO2017162164A1 - Electronic signature device transaction method

Info

Publication number: WO2017162164A1
Application number: PCT/CN2017/077652
Authority: WO
Inventors: 李东声
Original assignee: 天地融科技股份有限公司
Priority date: 2016-01-22
Filing date: 2017-03-22
Publication date: 2017-09-28
Also published as: CN105913256A; CN105956855B; CN105913255A; CN105956855A; CN105931048A; CN113159763A; CN105931049A

Abstract

An electronic signature device transaction method, comprising: an electronic signature device sending a transaction request to a server, wherein the transaction request at least comprises a transaction amount (S11); the server receiving the transaction request, deducting the transaction amount from a band account of the electronic signature device, acquiring at least one first unit data packet, and sending the at least one first unit data packet to the electronic signature device (S12), wherein each first unit data packet represents one currency denomination among a plurality of currency denominations, and the sum of the currency denominations represented by the at least one first unit data packet is equal to the transaction amount; and the electronic signature device receiving the at least one first unit data packet, and storing the at least one first unit data packet in a secure chip (S13). By means of the present solution, off-line electronic transaction can be realized.

Description

Electronic signature device transaction method

Cross-reference to related applications

This application is based on the Chinese patent application with the application number of 201610178325.8, the application date is March 25, 2016, and the application number is 201610178067.3, and the application date is March 25, 2016, and the priority of the above-mentioned Chinese patent application is required. The entire disclosure of the above-identified Chinese patent application is incorporated herein by reference.

Technical field

The invention relates to the field of electronic technology, and in particular to a method for trading an electronic signature device.

Background technique

In the existing electronic transaction, the user's funds are stored in the account in the form of numbers. For example, the user holds 100 yuan of funds, and the funds are stored in the user account of the bank server in the form of numbers. When the user consumes 10 yuan, The bank server needs to rewrite the funds 100 in the user account to 90 to complete the account clearing. In order to ensure the security of the fund value, after the bank server rewrites the value, the rewritten fund value 90 is signed. Because the value of the amount in the account changes every time the user makes a transaction, the bank server will process the value after each change. That is to say, the existing electronic transactions must rely on the bank server, and the electronic transactions performed by the users need to be synchronized with the bank server in real time, and it is impossible to independently complete multiple offline transactions without being connected to the Internet.

Summary of the invention

The present invention aims to solve at least one of the above problems.

The main object of the present invention is to provide a method of trading an electronic signature device.

Another object of the present invention is to provide a method of trading another electronic device.

In order to achieve the above object, the technical solution of the present invention is specifically implemented as follows:

A transaction method of an electronic signature device, comprising: an electronic signature device transmitting a transaction request to a server, wherein the transaction request includes at least: a transaction amount; the server receives the transaction request, and deducts the transaction amount from the bank account of the electronic signature device, Obtaining at least one first unit data packet, and transmitting at least one first unit data packet to the electronic signature device; wherein each first unit data packet represents one of a plurality of currency denominations, each first unit The data packet includes at least: the first unit data, the first signature data obtained by the server signing the first unit data, the sum of the currency denominations represented by the at least one first unit data packet is equal to the transaction amount; and the electronic signature device receives the at least one first And a unit data packet, where the first signature data in the at least one first unit data packet is verified, and after the verification is passed, the at least one first unit data packet is stored in the security chip.

According to the transaction method of the solution 1, the transaction request further includes: a device identifier of the electronic signature device; each first unit data packet further includes: a server obtained by signing the first unit data and the device identifier of the electronic signature device Two signature data; at least one first unit data packet is stored in the electronic signature device Before the security chip, the method further comprises: the electronic signature device verifying the second signature data, and performing the step of storing the at least one first unit data packet in the security chip after the verification is passed.

The method of claim 1 or 2, after the electronic signature device stores the at least one first unit data packet in the security chip, the method further comprises: the electronic signature device according to the received at least one first unit data packet The number and the currency denomination represented by each first unit data packet calculate whether the sum of the currency face values represented by the received first unit data packet is consistent with the transaction amount in the transaction request, and if not, send a retransmission to the server. Request; the server receives a resend request.

The method of claim 3, after the server receives the resend request, the method further includes: the server sending the retransmission information to the electronic signature device according to the retransmission request, wherein the retransmission information includes at least one first unit data packet; The electronic signature device receives the retransmission information, deletes at least one first unit data packet previously stored in the security chip, and re-stores at least one first unit data packet retransmitted by the server.

The method of claim 3, after the server receives the resend request, the method further includes: the server sending the retransmission information to the electronic signature device according to the retransmission request, where the retransmission information includes the first unreceived by the electronic signature device One unit data packet; the electronic signature device stores the unreceived first unit data packet in the security chip.

Item 6. The transaction method of any one of clauses 1 to 5, before the electronic signature device stores the at least one first unit data packet in the security chip, the method further comprising: the electronic signature device utilizing its security chip allocation for storing at least a storage space of the first unit data packet; the electronic signature device stores the at least one first unit data packet in the security chip, including: the electronic signature device stores the at least one first unit data packet in the corresponding storage space, and The status word of the corresponding storage space is set to be occupied.

The transaction method according to any one of claims 1 to 6, after the electronic signature device stores the at least one first unit data packet in the security chip, the method further comprises: the electronic signature device using the counter value of the counter to obtain the currently stored The total number of first unit packets.

Item 8. The transaction method according to any one of claims 1 to 7, after the electronic signature device stores the at least one first unit data packet in the security chip, the method further comprises: the electronic signature device counting the transaction amount into the current account balance, Display the transaction amount and/or current account balance to the holding user.

Item 9. The transaction method according to any one of the items 1 to 8, the first unit data includes at least: currency denomination data, or currency serial number and currency denomination data; the first unit data packet further includes at least one of the following: issuing bank identifier And the bank certificate serial number.

The transaction method of the electronic signature device described above can store the user's funds in the form of a data packet in the electronic signature device of the user, and the number of the data packets is one or more. When the user is consuming, since the funds are no longer stored in the electronic signature device in the form of numerical values, the electronic signature device does not need to change the stored value by networking with the server, and only needs one or more firsts that meet the consumption amount. The unit data packet can be sent to the payee. Therefore, the electronic signature device does not need to rely on the server for online payment when performing electronic transactions with other electronic signature devices, and the server no longer needs to supervise the electronic signature device, thereby truly Implement offline electronic trading.

The transaction method of the electronic signature device includes: the second electronic signature device sends the transaction request to the first electronic signature device, wherein the transaction request includes at least: a transaction amount; and the first electronic signature device receives the transaction request And obtaining at least one second unit data packet from its security chip, and transmitting at least one second unit data packet to the second electronic signature device, wherein each second unit data packet represents one of a plurality of currency denominations Currency denomination, each The second unit data packet includes at least: the second unit data, the third signature data obtained by the server signing the second unit data, the sum of the currency denominations represented by the at least one second unit data packet is equal to the transaction amount; and the second electronic signature device Receiving at least one second unit data packet, verifying the third signature data in the at least one second unit data packet, and storing the at least one second unit data packet in the security chip after the verification is passed.

The method of claim 10, after the first electronic signature device sends the at least one second unit data packet to the second electronic signature device, the method further includes: deleting, by the first electronic signature device, the acquired at least one second unit data pack.

The method of claim 10, wherein the first electronic signature device sends the at least one second unit data packet to the second electronic signature device, the first electronic signature device encrypting the at least one second unit data packet to obtain At least one third unit data packet, and transmitting the at least one third unit data packet to the second electronic signature device; the second electronic signature device receiving the at least one second unit data packet, including: the second electronic signature device receiving the at least one The three-unit data packet decrypts at least one third unit data packet to obtain at least one second unit data packet.

The method of claim 12, wherein the first electronic signature device encrypts the at least one second unit data packet, the first electronic signature device using the public key of the second electronic signature device for at least each second unit data The second unit data in the packet is encrypted to obtain the data ciphertext; the second electronic signature device decrypts the at least one third unit data packet, including: the second electronic signature device uses the private key of the second electronic signature device to at least The data ciphertext in the third unit data packet is decrypted.

The method of claim 13, after the first electronic signature device encrypts the at least one second unit data packet, the method further comprises: the first electronic signature device overwriting the security chip with each third unit data packet. Each second unit packet.

The method of claim 12, wherein the first electronic signature device encrypts the at least one second unit data packet, including: the first electronic signature device utilizes a symmetric key associated with the second electronic signature device, at least for each The second unit data in the two unit data packet is encrypted to obtain the data ciphertext; the second electronic signature device decrypts the at least one third unit data packet, including: the second electronic signature device uses the first electronic signature device The symmetric key decrypts at least the data ciphertext in each third unit data packet.

The method of claim 15, after the first electronic signature device encrypts the at least one second unit data packet, the method further includes: the first electronic signature device overwriting the security chip with each third unit data packet. Each second unit of data packets and delete the symmetric key.

The method of claim 15 or 16, wherein the symmetric key is an exclusive OR factor; the first electronic signature device utilizes a symmetric key associated with the second electronic signature device for at least a second of each second unit data packet The unit data is encrypted to obtain the data ciphertext, including: the first electronic signature device uses an exclusive OR factor to perform an exclusive OR operation on at least the second unit data in each second unit data packet to obtain a data ciphertext; the second electronic signature The device decrypts the data ciphertext in each third unit data packet by using a symmetric key associated with the first electronic signature device, including: the second electronic signature device uses an exclusive OR factor for each third unit data packet The data ciphertext in the XOR is XORed.

The transaction method according to any one of the items 10 to 17, after the second electronic signature device stores the at least one second unit data packet in the security chip, the method further comprises: the second electronic signature device utilizing the counter value of the counter The total number of second unit packets to the current storage.

The transaction method according to any one of the items 10 to 18, wherein the transaction request comprises at least: a device identifier of the second electronic signature device.

Item 20. The transaction method of claim 19, before the first electronic signature device acquires at least one second unit data packet from its security chip, the transaction method The method further includes: the first electronic signature device prompting the holding user with the transaction amount and the device identifier of the second electronic signature device, and receiving the confirmation information of the holding user.

The second unit data packet further includes: fourth signature data obtained by the first electronic signature device for the second unit data and the device identifier of the second electronic signature, and the second electronic data according to the transaction method of the party 19; Before the signing device stores the at least one second unit data packet in the security chip, the method further includes: the second electronic signature device verifies the fourth signature data, and after the verification is passed, executing the second electronic signature device to the at least one second unit The step of storing the data packet in the security chip.

The method of claim 19, wherein each third unit data packet further comprises: a device identifier of the second electronic signature device.

The transaction method according to any one of the items 10 to 22, wherein the second unit data packet comprises: a data packet identifier.

The method of claim 23, wherein the transaction request further comprises: a data packet identifier; the second electronic signature device stores the at least one second unit data packet in the security chip, and the second electronic signature device determines the received Whether the data packet identifier in the two-unit data packet is the same as the data packet identifier in the sent transaction request. If not, the second unit data packet with different data packet identifiers is discarded. If they are the same, the data packet identifier is the same. The second unit data packet is stored in the security chip.

The transaction method of claim 23, the transaction request further includes: a data packet identification start value; the second electronic signature device storing the at least one second unit data packet in the security chip, comprising: the second electronic signature device determining each Whether the data packet identifier included in the second unit data packet satisfies the preset range determined according to the start value of the data packet identifier, and if not, the second unit data packet whose data packet identifier does not satisfy the preset range is discarded, if If satisfied, the second unit data packet whose data packet identifier meets the preset range is stored in the security chip.

The method of claim 25, before the second electronic signature device sends the transaction request to the first electronic signature device, the method further includes: the second electronic signature device obtaining the data packet identification start value by using the counter value of the counter; After the second electronic signature device stores the at least one second unit data packet in the security chip, the method further includes: the counter of the second electronic signature device adds the data packet identifier start value to the received second unit data packet. The total number of calculations yields a new packet identification start value.

The transaction method according to any one of the items 23 to 26, after the second electronic signature device stores the at least one second unit data packet in the security chip, the method further comprises: the second electronic signature device according to the received The number of two unit data packets and the currency denomination value represented by each second unit data packet calculate whether the sum of the currency face values represented by the received second unit data packet is consistent with the transaction amount in the transaction request, and if they are inconsistent, Sending a retransmission request to the first electronic signature device; the first electronic signature device receives the retransmission request, and sends the retransmission information to the second electronic signature device according to the retransmission request, wherein the retransmission request includes at least the second electronic signature The device identifier of the device and/or the packet identifier corresponding to each second unit data packet.

The method of claim 27, after the first electronic signature device sends the retransmission information to the second electronic signature device according to the retransmission request, the method further includes: the second electronic signature device receiving the retransmission information, wherein The sending information includes at least one second unit data packet, and the at least one second unit data packet previously stored in the security chip is deleted, and the at least one second unit data packet retransmitted by the first electronic signature device is re-stored.

The method of claim 27, after the first electronic signature device sends the retransmission information to the second electronic signature device according to the retransmission request, the method further includes: the second electronic signature device receiving the retransmission information, wherein The sending information includes a second unit data packet that is not received by the second electronic signature device, and stores the unreceived second unit data packet in its security chip.

The transaction method according to any one of the items 10 to 29, wherein the second unit data includes at least: currency denomination data, or currency serial number and currency denomination data; and the second unit data packet includes at least one of the following: issuing bank identification and Bank certificate serial number.

The method of any one of the aspects 10 to 30, after the first electronic signature device transmits the at least one second unit data packet to the second electronic signature device, the method further comprises: the first electronic signature device to have its account The amount is subtracted from the transaction amount to obtain the current account balance, and the transaction amount and/or the current account balance are displayed to the holding user; after the second electronic signature device stores the at least one second unit data packet in the security chip, the method further includes: The second electronic signature device adds the current account amount to the transaction amount to obtain the current account balance, and displays the transaction amount and/or the current account balance to the holding user.

The method of any one of the aspects 10 to 31, before the second electronic signature device stores the at least one second unit data packet in the security chip, the method further comprises: distributing the security chip of the second electronic signature device And storing the storage space of the at least one second unit data packet; the second electronic signature device storing the at least one second unit data packet in the security chip, the second electronic signature device storing the at least one second unit data packet in the corresponding In the storage space, and set the status word of the corresponding storage space to be occupied.

The method of claim 27, wherein before the first electronic signature device transmits the at least one second unit data packet to the second electronic signature device, the method further comprises: a security chip of the first electronic signature device Allocating a storage space for storing at least one third unit data packet, and storing at least one third unit data packet in the corresponding storage space; and transmitting, by the first electronic signature device, the retransmission information to the second according to the retransmission request After the electronic signature device, the method further includes: the first electronic signature device receiving the confirmation message of the success of the reception returned by the second electronic signature device, and modifying the status word of the storage space of the at least one third unit data packet to be completed. Or empty the storage space.

With the above-described electronic signature device transaction method, the user's funds are stored in the first electronic signature device or the second electronic signature device in the form of at least one second unit data packet. When the payee user (the second electronic signature device side) receives the second unit data packet, since the funds are no longer stored in the second electronic signature device in the form of numerical values, the second electronic signature device does not need to be changed by the server. The stored value, the second electronic signature device of the payee user only needs to receive a certain number of second unit data packets from the first electronic signature device of the payer user, whereby the electronic signature device is signed with other electronic When the device conducts electronic transactions, it no longer needs to rely on the server for online payment, and the server does not need to supervise the electronic signature device of the payee user or the payer user, thereby realizing offline electronic transactions.

DRAWINGS

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly described below. It is obvious that the drawings in the following description are only some embodiments of the present invention, Those of ordinary skill in the art will be able to obtain other figures from these drawings without the inventive effort.

1 is a flowchart of a method for processing an electronic signature device according to Embodiment 1 of the present invention;

FIG. 2 is a flowchart of another method for processing an electronic signature device according to Embodiment 2 of the present invention.

detailed description

The technical solutions in the embodiments of the present invention are clearly and completely described in the following with reference to the drawings in the embodiments of the present invention. It is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present invention without creative efforts are within the scope of the present invention.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", " The orientation or positional relationship of the indications of "upright", "horizontal", "top", "bottom", "inside", "outside", etc. is based on the orientation or positional relationship shown in the drawings, only for the convenience of describing the present invention and The simplification of the description is not intended to limit or imply that the device or component that is referred to has a particular orientation, is constructed and operated in a particular orientation, and thus is not to be construed as limiting. Moreover, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or quantity or location.

In the description of the present invention, it should be noted that the terms "installation", "connected", and "connected" are to be understood broadly, and may be fixed or detachable, for example, unless otherwise explicitly defined and defined. Connected, or integrally connected; can be mechanical or electrical; can be directly connected, or indirectly connected through an intermediate medium, can be the internal communication of the two components. The specific meaning of the above terms in the present invention can be understood in a specific case by those skilled in the art.

The embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

Example 1

FIG. 1 is a flowchart of a method for processing an electronic signature device according to an embodiment of the present invention. The method embodiment shown in FIG. 1 includes the following steps S11 to S13:

Step S11: The electronic signature device sends a transaction request to the server, wherein the transaction request includes at least: a transaction amount.

In this embodiment, the electronic signature device may be an electronic device with a signature function, for example, a smart card with a signature function (a bus card, a bank card, a shopping card, etc.), a U shield of the ICBC, and the like. In an optional implementation manner of this embodiment, the electronic signature device sends a transaction request to the server. Specifically, the electronic signature device may establish a connection with an external device (such as a PC or a mobile terminal, etc.), and the transaction is performed by the external device. The request is sent to the server. Alternatively, the electronic signature device has a wired interface or a wireless interface, establishes a wired connection or a wireless connection with the server, and directly sends the transaction request to the server. Among them, the wireless connection method may include Bluetooth, NFC approach communication, and WIFI. Thus, the electronic signature device in this embodiment can send a transaction request to the server in a variety of ways. As an optional implementation manner, the server includes a bank server or a third-party server. For example, the third-party server may be a shopping card stored value server of a certain mall.

For example, the electronic signature device needs to perform a recharge operation, and sends a transaction request for refilling to the server (the bank server or the shopping card stored value server of the shopping mall), and the transaction amount carried in the transaction request is the electronic signature device requesting the server. The value of the recharge amount, so that the server returns the first unit data packet corresponding to the transaction amount to the electronic signature device (ie, the sum of the currency denominations of the first unit data packet returned by the server is equal to the transaction amount).

Step S12, the server receives the transaction request, deducts the transaction amount from the bank account of the electronic signature device, acquires at least one first unit data packet, and transmits the at least one first unit data packet to the electronic signature device;

Each of the first unit data packets represents one of a plurality of currency denominations, and each of the first unit data packets includes at least: the first unit data, and the first signature obtained by the server to sign the first unit data. Data, the sum of the currency denominations represented by the at least one first unit data packet is equal to the transaction amount.

In this embodiment, each first unit data packet represents one currency face value of the plurality of currency denominations, that is, the currency face value has a plurality of types, when the electronic signature is set When a first unit data packet is received only from the server, the first unit data packet represents only one of the currency denominations. When the electronic signature device receives a plurality of first unit data packets from the server, the plurality of first unit data packets may represent a plurality of different currency denominations, for example, the number of the first unit data packets is three, each of the first One unit data packet represents currency face value of 1 yuan, 2 yuan and 5 yuan respectively; or, multiple first unit data packets can represent the same currency face value, for example, the number of first unit data packets is 3, each A unit data packet represents a currency denomination of 1 yuan; or, a plurality of first unit data packets represent a currency denomination that includes both the same and different currency denominations, for example, the number of first unit data packets is 3, each first unit data packet represents currency face value of 1 yuan, 1 yuan and 2 yuan. Thus, the currency denomination represented by the at least one first unit data packet received by the electronic signature device from the server has a flexible combination.

In an optional implementation manner of this embodiment, the first unit data packet includes at least first unit data, and the first unit data includes at least: currency denomination data, or currency serial number and currency denomination data. Wherein, the currency denomination data is the currency denomination represented by the first unit data packet, thereby identifying the currency denomination represented by the first unit data packet, and the currency serial number is the unique serial number of each first unit data packet, that is, different numbers The currency numbers in a unit of data packets are different. Thereby, the uniqueness of each first unit data packet can be guaranteed to facilitate identification of the authenticity of the first unit data packet. As an optional implementation manner, the first unit data packet further includes at least one of the following: an issuing bank identifier and a bank certificate serial number. The issuing bank identifier is the identification information of the bank that issued the first unit data packet, so that the related information of the corresponding issuing bank can be queried according to the identifier, and the electronic signature device can obtain the identifier according to the issuing bank identifier and the bank certificate serial number. Corresponding bank certificate of the issuing bank, the bank certificate contains the public key of the issuing bank, so that the electronic signature device can verify the signature of the first unit data by using the public key of the issuing bank in the subsequent operation.

In an optional implementation manner of this embodiment, the first unit data packet further includes: first unit data and first signature data obtained by the server to sign the first unit data. As an optional implementation manner, the server separately signatures the first unit data in each first unit data packet by using its own private key, to obtain first signature data corresponding to each first unit data packet. The server sends at least one first unit data packet carrying the first signature data to the electronic signature device, so that the electronic signature device uses the public key of the server to verify the authenticity of the first unit data packet in subsequent operations.

In another optional implementation manner of this embodiment, the transaction request sent by the electronic signature device to the server further includes: a device identifier of the electronic signature device; each first unit data packet further includes: the server to the first unit data And the second signature data obtained by the device identification signature of the electronic signature device. As an optional implementation manner, the server uses the private key of the server to sign the first unit data and the device identifier of the electronic signature device to obtain second signature data corresponding to each first unit data packet. The server sends at least one first unit data packet carrying the second signature data to the electronic signature device, so that the electronic signature device uses the public key of the server to verify the correctness of the first unit data packet in subsequent operations.

In this embodiment, after receiving the transaction request sent by the electronic signature device, the server deducts the transaction amount requested by the electronic signature device from the account corresponding to the electronic signature device, and the sum of the currency denominations issued by the electronic signature device is equal to At least one first unit data packet of the transaction amount, after the electronic signature device receives the first unit data packet, that is, after the recharging is successful, the offline transaction can be completed with other electronic signature devices, that is, the network connection with the server is not needed. Transfer money to other electronic signature devices (ie, forward the first unit data packet to other electronic signature devices). The currency face value represented by each first unit data packet may be the same or different, and the number of first unit data packets sent to the electronic signature device and the currency face value represented by each first unit data packet may be determined by the server according to the transaction amount. It is determined that the electronic signature device can also notify the server after determining the transaction amount. For example, as an optional implementation manner in this embodiment, the transaction request sent by the electronic signature device may further carry the type of the first unit data packet and Number. The former server can flexibly implement the delivery of the first unit data packet, and the latter can The user's demand for the number of first unit data packets and the face value is satisfied. In an optional implementation manner of this embodiment, each first unit data packet represents one of a plurality of currency denominations. For example, the currency denomination represented by the first unit data packet includes: 1 yuan, 2 Yuan, 5 yuan, 10 yuan, 20 yuan, 50 yuan and 100 yuan. Of course, if the future country issues a new currency denomination, or other regions other than the RMB, the currency face value of the country is also within the scope of protection of the present invention. In this embodiment, only the RMB denomination is used for illustration. For example, the electronic signature device sends a transaction request to the server, wherein the transaction request includes a transaction amount of 10 yuan, and the electronic signature device receives 5 first unit data packets from the server, and the currency face value represented by the 5 first unit data packets The sum of the currency denominations represented by the five first unit data packets is 1 yuan, 1 yuan, 1 yuan, 2 yuan, and 5 yuan, respectively, which is equal to the transaction amount. Of course, when the transaction request includes a transaction amount of 10 yuan, the electronic signature device may also receive 10 first unit data packets representing the face value of the 1 dollar currency from the server, or 2 first unit data representing the face value of the 5 dollar currency. Package, or, a first unit packet representing the face value of a 10-yuan currency. That is to say, the currency denomination and the number represented by the first electronic unit currency data packet can be flexibly combined, and only the sum of the currency denominations represented by the received at least one first unit data packet is equal to the transaction amount. The transaction amount is only 10 yuan as an example. For other amounts, the numerical principle is the same, and is not illustrated here. Therefore, in the case that the server determines the number of the first unit data packets according to the transaction amount and the face value represented by each of the first unit data packets, the server can flexibly implement the delivery of the first unit data packet, and various types of data packets can be implemented. Combining; in the case where the electronic signature device determines the number of the first unit data packets according to the transaction amount, and the face value represented by each first unit data packet, the number of requests and the corresponding first unit data packet may be represented. The currency face value is sent to the server, thereby satisfying the user's demand for the number of first unit data packets and the face value.

In an optional implementation manner of the embodiment, the electronic signature device may further receive at least one ciphertext of the first unit data packet from the server, in order to further improve the security of the data transmission in the process of delivering the first unit data packet by the server. Data, wherein the ciphertext data is obtained by the server encrypting at least one first unit data packet, and the electronic signature device may decrypt the ciphertext data to obtain the first unit data packet original text, and the server and the electronic signature device may pass the symmetric key Secure encryption of data is achieved by means of key encryption or decryption or asymmetric key encryption and decryption. As an optional manner, the server encrypts the at least one first unit data packet by using: the server encrypts the at least one first unit data packet by using the public key of the electronic signature device (this is an asymmetric key encryption). Alternatively, the server encrypts the at least one first unit data packet using a symmetric key negotiated with the electronic signature device. After receiving the ciphertext data, the electronic signature device decrypts the ciphertext data by using a decryption method corresponding to the encryption mode of the server, to obtain at least one first unit data packet plaintext, that is, using the private key of the electronic signature device to the secret The text data is decrypted to obtain the first unit data packet plaintext (this is the way of asymmetric key decryption), or the electronic signature device decrypts the ciphertext data by using the symmetric key negotiated with the server to obtain the first unit data packet plaintext. Thereby, the first unit data packet can be prevented from being copied or falsified during the transmission process, thereby improving the security of data transmission.

Step S13: The electronic signature device receives the at least one first unit data packet, and verifies the first signature data in the at least one first unit data packet, and after the verification is passed, stores the at least one first unit data packet in the security. In the chip.

In an optional implementation manner of the embodiment, the electronic signature device is provided with a security chip, and the security chip has an independent processor and a storage unit, and can store the PKI digital certificate and the key, and other characteristic data. The data is subjected to encryption and decryption operations to provide data encryption and identity security authentication services for the user. In this embodiment, the first unit data packet stored in the security chip of the electronic signature device cannot be illegally read, and the stored data security can be ensured.

In this embodiment, before the step S13, the transaction method further includes: the electronic signature device uses its security chip allocation for storing the at least one first unit. The storage space of the packet. The electronic signature device in step S13 stores the at least one first unit data packet in the security chip, and specifically includes: the electronic signature device stores the at least one first unit data packet in a corresponding storage space, and stores the corresponding storage. The status word for the space is set to Occupied. The security chip allocates one storage space for each first unit data packet, and one storage space can only store one first unit data packet, and the transaction record of the electronic signature device also records the transaction received from the server in a transaction. The location of the storage space stored by each first unit packet. The status word of the storage space is used to identify whether the storage space has been occupied. If it is already occupied, the electronic signature device cannot store the first unit data packet in the occupied storage space. When all the storage space allocated by the security chip is occupied, the electronic signature device needs to perform an operation of requesting the server to update the data packet or apply for a new storage space, wherein, as an optional implementation manner, the electronic signature device can apply for a new one. Storage space to store the newly received first unit packet. As another optional implementation manner, the electronic signature device may further request the server to update the locally stored first unit data packet. For example, the electronic signature device may request the server to store N locally (N is a positive integer greater than 1 The first unit data packet representing the small face value is replaced by 1 or M (M < N), the first unit data packet representing the face value of the large currency is stored, as long as the stored currency amount is unchanged, thereby releasing Multiple storage spaces, thereby saving storage space to store the newly received first unit data packet. In addition, in order to further improve the security of the data storage, in the embodiment, the electronic signature device may further encrypt each first unit data packet to obtain ciphertext data of each first unit data packet, and each confidentiality The text data is stored in the corresponding storage space. Thereby, it can be ensured that the first unit data packet stored in the storage space of the security chip cannot be maliciously copied or changed, thereby ensuring the security of storing the first unit data packet.

In this embodiment, in order to further ensure the authenticity of the first unit data packet stored by the electronic signature device, the electronic signature device verifies the first signature data, and stores the at least one first unit data packet in the security after the verification is passed. In the chip. The first signature data is obtained by the server signing the first unit data. Therefore, in an optional implementation manner of the embodiment, each first unit data packet includes at least: the first unit data and the server pair. The first unit data is signed by the first unit data, thereby enabling the electronic signature device to verify the authenticity of the first unit data packet. As an optional implementation manner, the first signature data is signature data obtained by the server by using the private key of the server to sign the first unit data. Correspondingly, the verifying the first signature data by the electronic signature device comprises: the electronic signature device performing the verification of the first signature data by using the public key of the server. Taking the server as the bank server as an example, the bank server performs HASH operation on the first unit data to obtain the digest message A1 of the first unit data, and uses the private key of the bank server to sign the digest message A1 to obtain the first signature. The data is carried in the first unit data packet and sent to the electronic signature device. The electronic signature device can perform the verification of the first signature data by using the public key of the bank server. Specifically, the electronic signature device uses the public key of the bank server to calculate the first electronic signature data to obtain the operation result A2, and obtains the operation result A2. The first unit data in the first unit data packet is subjected to HASH operation to obtain the digest message A3 of the first unit data, and the operation result A2 is compared with the digest message A3. If the comparison result is consistent, the electronic signature device pairs An electronic signature data check was passed. The electronic signature device may obtain the public key of the bank according to the bank certificate serial number and/or the issuing bank identifier in the first unit data packet. For example, the electronic signature device may wait and receive according to the issuing bank identifier in the first unit data packet. The issuing bank server corresponding to the verified first signature data obtains the bank certificate of the bank, and obtains the bank's public key from the bank certificate; for example, the electronic signature device can pre-store the bank certificate of each bank according to the first unit data packet. The bank certificate serial number in the bank certificate is obtained from the pre-stored bank certificate, and the bank certificate corresponding to the first signature data to be verified is obtained, and the bank public key is obtained from the corresponding bank certificate. Therefore, the electronic signature device uses the public key of the bank to perform verification on the first signature data carried in the first unit data packet, and can verify the authenticity of the first unit data packet. The above description is only taking the server as a bank server as an example, but the embodiment is not limited to the bank server, and the specific implementation manners of other third-party servers, such as a supermarket shopping card stored value server, etc. belong to the protection scope of the present invention. Within the fence.

Further, the electronic signature device further confirms whether the object sent by the server is indeed the electronic signature device, so as to ensure that the data packet sent by the storage server is incorrect, in the step of ensuring that the received first unit data packet is authentic. Before storing at least one first unit data packet in the security chip in S13, the transaction method further includes: the electronic signature device verifying the second signature data, and executing the storing the at least one first unit data packet after the verification is passed Operation in the security chip. The second signature data is obtained by the server for the first unit data and the device identifier of the electronic signature device. Therefore, in an optional implementation manner of the embodiment, the transaction request sent by the electronic signature device to the server further includes: The device identifier of the electronic signature device; each first unit data packet includes at least: first unit data, second signature data obtained by the server for the first unit data and the device identifier of the electronic signature device, thereby enabling the electronic signature device to Verify the authenticity and correctness of the first unit packet. As an optional implementation manner, the second signature data is signature data obtained by the server by using the private key of the server to sign the device identifier of the first unit data and the electronic signature device, that is, each second signature data. The signature object is a combination of each of the first unit data and the device identification of the electronic signature device. Correspondingly, the verifying the second signature data by the electronic signature device comprises: the electronic signature device separately checking each second signature data by using a public key of the server. Taking the server as the bank server as an example, the bank server uses the private key of the server to sign the first unit data and the device identifier of the electronic signature device to obtain the second signature data, which is carried in the first unit data packet and sent to the electronic signature device. . The electronic signature device can authenticate the second signature data by using the public key of the bank server. The electronic signature device may obtain the bank certificate of the bank according to the bank certificate serial number and/or the issuing bank identifier in the first unit data packet, and obtain the public key of the bank from the bank certificate. For example, the electronic signature device may be configured according to the The issuing bank identifier in one unit data packet acquires the public key of the bank from the issuing bank server corresponding to the second signature data to be verified; for example, the electronic signature device may pre-store the bank certificate of each bank according to the first unit data The bank certificate serial number in the package obtains the bank certificate corresponding to the second signature data to be verified from the pre-stored bank certificates, and obtains the bank public key from the corresponding bank certificate. Therefore, the electronic signature device uses the public key of the bank to perform verification on the second signature data carried in the first unit data packet, which can not only verify the authenticity of the first unit data packet, but also prove that the first unit data packet is indeed The bank server sends the electronic signature device to the electronic signature device to verify the correctness of the first unit data packet. The foregoing description is only for the example that the server is a bank server, but the embodiment is not limited to the bank server, and the specific implementation manners of other third-party servers, such as a supermarket shopping card stored value server, are within the protection scope of the present invention.

In order to ensure that the electronic signature device does not receive less money, that is, the total amount of the first unit data packet received by the electronic signature device is equal to the transaction amount, in an optional implementation manner of this embodiment, after the step S13, the transaction The method further includes: calculating, by the electronic signature device, the currency face value represented by the received first unit data packet according to the received number of the at least one first unit data packet and the currency face value represented by each first unit data packet The sum is consistent with the transaction amount in the transaction request, and if not, the retransmission request is sent to the server; the server receives the retransmission request. For example, if the transaction amount is 10 yuan, the electronic signature device receives 5 first unit data packets from the server, and calculates whether the sum of the currency face values represented by the 5 first unit data packets is equal to 10 yuan, and if less than 10 yuan, the server Send a resend request. Thus, the electronic signature device can solve the problem of insufficient currency face value represented by the received first unit data packet by transmitting a retransmission request to the server.

After the electronic signature device sends a resend request to the server, the electronic signature device receives the retransmission information returned by the server. According to the content of the retransmission request, the retransmission information returned by the server may be different. For example, the retransmission request may be The device identification and transaction record of the electronic signature device (such as the number of each transaction, account information, time stamp, transaction amount, and the number of received first unit data packets and the currency face value represented, etc.) Will also correspond to the record), In order to facilitate the server to query a certain transaction corresponding to the electronic signature device, all the first unit data packets corresponding to the transaction are resent to the electronic signature device, and, for example, the retransmission request may also carry the received first unit. The packet identifier of the data packet (which can uniquely identify the identifier of a first unit data packet, such as the unique identifier configured by the server for each first unit data packet, or the currency serial number). After receiving the data packet identifiers, the server can query Which first unit data packets are lost during the missed transmission or transmission, and the first unit data packets that are lost or lost during transmission are sent to the electronic signature device. The following is an exemplary illustration of the server resending the first unit of electronic data packets:

For example, after the server receives the retransmission request, the transaction method further includes: the server transmitting the retransmission information to the electronic signature device according to the retransmission request, wherein the retransmission information includes at least one first unit data packet; and the electronic signature device receives the retransmission And deleting at least one first unit data packet previously stored in the security chip, and re-storing at least one first unit data packet retransmitted by the server. As an optional implementation, the electronic signature device, after sending the resend request to the server, receives the retransmission information sent by the server according to the retransmission request, where the retransmission request includes at least: the device identifier of the electronic signature device and The transaction record, the retransmission information includes at least one first unit data packet, that is, in the optional implementation, the server resends all the first unit data packets corresponding to a transaction to the electronic signature device, in this embodiment. When the server deals with the unit electronic signature tool, it also stores the transaction records corresponding to each transaction (such as the number of each transaction, account information, time stamp, transaction amount, and the number of first unit packets sent). And the device identifier of the electronic signature device, and the device identifier of the electronic signature device, according to the device identifier and the transaction record, a certain transaction corresponding to the electronic signature device can be queried, in the optional implementation manner, the server will query The first unit data packet of the transaction that the electronic signature device requests to resend is resent to the electronic signature set. To ensure that the electronic signature device receives the correct transaction complete first unit of data packets, the server and the electronic signature device (such as a top-correct).

In order to ensure that the electronic signature device does not repeatedly store the data packet, before the electronic signature device receives the first unit data packet retransmitted by the server, the transaction method further includes: the electronic signature device storing the at least one first stored in the security chip. Unit data packet deletion (ie, in this alternative embodiment, since the server will resend the first unit data packet of the transaction to the electronic signature device, the electronic signature device must all the previously received transactions. a unit data packet, that is, at least one first unit data packet corresponding to the transaction previously stored in the security chip is deleted, and re-storing at least one first unit data packet retransmitted by the server, wherein the electronic signature device is executing After the operation of deleting the first unit data packet is performed, the status word of the occupied storage space is set to be unoccupied, and the electronic signature device can store the re-received first unit data packet into the storage space allocated by the previous security chip. And set the status word of the occupied storage space to be occupied, thereby ensuring the electronic signature Preparation will not repeat unit storing a first data packet, and to ensure that the same storage unit can only store a first packet.

For example, for a transaction numbered 1*******, the transaction amount in the transaction request of the electronic signature device is 10 yuan, and the electronic signature device receives 5 values representing the face value of the 2 yuan currency respectively sent by the server. The first unit data packet, but due to data loss during transmission, the electronic signature device only receives four first unit data packets respectively representing the denomination of the 2-yuan currency, and the sum of the currency denominations is 8 yuan, which is not equal to the transaction amount of 10 yuan. For the transaction, the electronic signature device sends a retransmission request to the server, and receives retransmission information sent by the server according to the retransmission request, where the retransmission request includes: a device identifier of the electronic signature device and a transaction record, and the server receives the After the request is resent, the transaction corresponding to the electronic signature device may be queried according to the device identifier and the transaction record, and the server resends the first unit data packet of the transaction that the queried electronic signature device requests to resend to the transaction. The electronic signature device, that is, the retransmission information sent by the server to the electronic signature device, includes five first unit data packets respectively representing the denomination of the 2-yuan currency. The electronic signature device stores the four previously stored in the security chip for the two-yuan currency. The first unit packet of the denomination is deleted, and the first unit packet representing the denomination of the 2-yuan currency, respectively, is re-stored by the server. Thus, when the electronic signature device does not receive all of the first unit data packets required for a transaction, the server can resend all of the first unit data packets required for the transaction to the electronic signature device, thereby enabling the transaction to enable the transaction. Done successfully.

For another example, after the server receives the resend request, the transaction method further includes: the server sending the retransmission information to the electronic signature device according to the retransmission request, wherein the retransmission information includes the first unit data packet that is not received by the electronic signature device. The electronic signature device stores the unreceived first unit data packet in the security chip.

As an optional implementation, the electronic signature device, after sending the resend request to the server, receives the retransmission information sent by the server according to the retransmission request, where the retransmission request includes at least: the device identifier of the electronic signature device, a transaction record and a received packet identifier of each first unit data packet, the retransmission information including a first unit data packet not received by the electronic signature device, that is, in the optional embodiment, the server is heavy to the electronic signature device A first unit data packet missed or lost during transmission is sent, and a corresponding transaction corresponding to the electronic signature device can be queried according to the device identification and the transaction record, and the server will query the electronic signature. The first unit data packet corresponding to the unidentified data packet identifier of the transaction requesting retransmission of the device is resent to the electronic signature device to ensure that the electronic signature device receives the complete first unit data packet, the server and the electronic signature. The transaction of the equipment is correct (such as recharge). Compared with the optional implementation in the previous example, the optional implementation manner can reduce the data transmission volume of the server, greatly reduce the workload of the server, and improve the working efficiency of server retransmission.

In the optional implementation, after the electronic signature device receives the first unit data packet resent by the server, the electronic signature device stores the first unit data packet that has not been received before in the security chip, that is, the electronic signature device The re-received first unit data packet is stored in the storage space allocated before the security chip, and the status word of the occupied storage space is set to be occupied, thereby ensuring that only one first unit data packet can be stored in the same storage space.

For example, for a transaction numbered 1*******, the transaction amount in the transaction request of the electronic signature device is 5 yuan, and the electronic signature device receives two of the two face currency values respectively sent by the server. The first unit data packet (referred to as a 2-yuan data packet), and a first unit data packet (referred to as a 1-yuan data packet) representing a denomination of a 1-yuan currency, but the electronic signature device only receives 2 due to data loss during transmission. A 2-yuan data packet, the sum of currency face values is 4 yuan, which is not equal to the transaction amount of 5 yuan. For the transaction, the electronic signature device sends a retransmission request to the server, and receives the retransmission information sent by the server according to the retransmission request, and the retransmission request further carries the data packet identifier of two 2-yuan data packets, and the server receives the packet identifier. After the retransmission request, the transaction for the electronic signature device can query all the corresponding first unit data packets, and then the packet identifier of the unrequested data packet in the retransmission request can be found, and the server can The metadata packet is retransmitted to the electronic signature device, that is, the retransmission information sent by the server to the electronic signature device includes one 1-yuan data packet. The electronic signature device stores one 1-byte data packet retransmitted by the server in the security chip. In this embodiment, the retransmission request sent by the electronic signature device to the server may include the data packet identifier of the part of the first unit data packet that has been received, and the server may determine the retransmission information according to the data packet identifier in the retransmission request. The first unit packet that needs to be carried. Therefore, when the electronic signature device does not receive all the first unit data packets required for a transaction, the server may resend some of the first unit data packets that are not received to the electronic signature device, thereby reducing retransmission data. The amount of transmission also ensures that the transaction can be completed smoothly.

The above is described by taking an implementation manner of a transaction as an example. In this embodiment, each transaction in a plurality of transactions can be implemented in the above manner.

In this embodiment, the storage space of the electronic signature device is limited after all. Therefore, the remaining space of the electronic signature device needs to be monitored at any time, so as to release the storage space in an instant, and avoid the problem that the transaction fails if there is no extra space in the transaction process. In an optional implementation manner of this embodiment, the electronic signature device is further configured. A counter is provided through which the remaining storage space of the electronic signature device can be monitored in real time. Specifically, after the step S13, the transaction method further includes: the electronic signature device uses the count value of the counter to obtain the total number of the first unit data packets currently stored. Specifically, in each transaction, the counter adds the number of the first unit data packet received by the transaction, and after multiple transactions, the counter value of the counter is accumulated to a value when the value reaches a preset value. When the storage space of the electronic signature device has been allocated, there is no redundant storage space. At this time, the electronic signature device needs to perform an operation of requesting the server to update the data packet or apply for a new storage space (as described above). In this embodiment, each storage space has the same size, and each first unit data packet has the same size and matches the size of the storage space, for example, the storage space allocated by the electronic signature device to a first unit data packet. The size is 2M, the 2M storage space can store a first unit data packet, and a security chip reserves the space for storing the first unit data packet as 1G, then the electronic signature device can store up to 512 first unit data. The package, the preset value can be set to 512. Thereby, the remaining space of the electronic signature device can be monitored in real time, and the redundant storage space is released in time, so as to avoid the problem that the transaction fails if there is no extra space in the transaction process. Of course, the electronic signature device can also use the count value of the counter to obtain the total number of first unit data packets of each currency denomination stored in the security chip. Thus, the electronic signature device can obtain the total amount of money of the currently stored first unit data packet according to the currency face value and the number of the money represented by each stored first unit data packet.

In an optional implementation manner of this embodiment, after the step S13, the transaction method further includes: the electronic signature device includes the transaction amount into the current account balance, and displays the transaction amount and/or the current account balance to the holding user. Thus, the user holding the electronic signature device can query the transaction amount and the current account balance on his own device.

With the transaction method of the electronic signature device provided in this embodiment, the user's funds can be stored in the user's electronic signature device in the form of data packets, and the number of data packets is one or more. When the user is consuming, since the funds are no longer stored in the electronic signature device in the form of numerical values, the electronic signature device does not need to change the stored value by networking with the server, and only needs one or more firsts that meet the consumption amount. The unit data packet can be sent to the payee. Therefore, the electronic signature device does not need to rely on the server for online payment when performing electronic transactions with other electronic signature devices, and the server no longer needs to supervise the electronic signature device, thereby truly Implement offline electronic trading.

Example 2

FIG. 2 is a flowchart of another method for processing an electronic signature device according to an embodiment of the present invention. As shown in FIG. 2, the transaction method includes the following steps S21 to S23:

Step S21: The second electronic signature device sends a transaction request to the first electronic signature device, where the transaction request includes at least: a transaction amount;

In this embodiment, the first electronic signature device and the second electronic signature device can perform offline transactions (ie, no need to complete the transaction with the server), and both can be electronic devices with a signature function, for example, having a signature function. Smart cards (bus cards, bank cards, shopping cards, etc.), U-Shields from ICBC, etc. In an optional implementation manner of the embodiment, the first electronic signature device and the second electronic signature device may each be provided with a wired interface or a wireless interface, and the second electronic signature device may be connected to the first electronic device by using a wired or wireless connection. The signing device establishes a communication connection, wherein the wireless connection manner includes but is not limited to: Bluetooth, NFC near field communication or WIFI. Of course, the second electronic signature device can also establish a connection with the external device through a wired or wireless connection, and send a transaction request to the first electronic signature device through the external device, and the first electronic signature device can also connect to the external device through a wired or wireless connection. Establishing a connection, and receiving, by the external device, a transaction request sent by the second electronic signature device, where the external device includes but is not limited to: an electronic device capable of communicating, such as a mobile phone, a PC, or a tablet computer. Thus, two electronic signatures The device can directly receive the transaction request of the other party, and then execute the subsequent transaction process, and no need to network with the background server to obtain the transaction request of the other party, execute the subsequent transaction process, and realize the offline transaction in a true sense.

For example, when the user purchases at the mall, when the payment is needed, the second electronic signature device of the cashier at the mall sends a transaction request carrying the transaction amount to the first electronic signature device of the user, and the transaction amount is the amount that the user needs to pay for the purchase. So that the first electronic signature device sends the second unit data packet corresponding to the transaction amount to the second electronic signature device (ie, the sum of the currency denominations of the second unit data packet sent by the first electronic signature device is equal to the transaction amount), two The electronic signature devices can be completely independent and do not need to be connected to the network. For example, the above transactions can be realized between two cards, and offline transactions can be realized, and the transaction is simple and quick.

In order to further improve the security of the data transmission between the two electronic signature devices, in an optional implementation manner of the embodiment, the second electronic signature device may establish a secure channel with the first electronic signature device. And use the secure channel for data transmission. Thereby, the security of data transmission between the second electronic signature device and the first electronic signature device can be improved.

Step S22: The first electronic signature device receives the transaction request, and acquires at least one second unit data packet from the security chip, and sends the at least one second unit data packet to the second electronic signature device.

Wherein, each second unit data packet represents one currency face value of the plurality of currency denominations, and each second unit data packet includes at least: the second unit data, and the third signature data obtained by the server for signing the second unit data, The sum of the currency denominations represented by the at least one second unit data packet is equal to the transaction amount;

In this embodiment, each second unit data packet represents one currency denomination of the plurality of currency denominations, and the sum of the currency denominations represented by the at least one second unit data packet is equal to the transaction amount.

In this embodiment, each second unit data packet represents one of a plurality of currency denominations, that is, a plurality of currency denominations are used, and when the first electronic signature device transmits only one second unit data packet to In the case of the second electronic signature device, the second unit data packet represents only one of the currency denominations. The second unit data packet in this embodiment has the same features as the first unit data packet provided in Embodiment 1. For a detailed description of the second unit data packet, refer to the first unit data packet in Embodiment 1. Description, no longer repeat here.

In an optional implementation manner of this embodiment, the second unit data packet includes at least second unit data, and the second unit data includes at least: currency denomination data, or currency serial number and currency denomination data. Wherein, the currency denomination data is the currency denomination represented by the second unit data packet, thereby identifying the currency denomination represented by the second unit data packet, and the currency serial number is the unique serial number of each second unit data packet, that is, different numbers The currency numbers in the two-unit data package are different. Thereby, the uniqueness of each second unit data packet can be guaranteed to facilitate identification of the authenticity of the second unit data packet. As an optional implementation manner, the second unit data packet further includes at least one of the following: an issuing bank identifier and a bank certificate serial number. The issuing bank identifier is the identification information of the bank that issues the second unit data packet, and the second electronic signature device can query the related information of the corresponding issuing bank according to the identifier, and the second electronic signature device can The issuing bank identifier and the bank certificate serial number are used to obtain the corresponding bank certificate of the issuing bank, and the bank certificate includes the issuing bank's public key, so that the subsequent second electronic signature device can verify the signature of the second unit data by using the issuing bank's public key. .

In an optional implementation manner of this embodiment, each second unit data packet includes at least: second unit data, and third signature data obtained by the server to sign the second unit data. As an optional implementation manner, the server separately signs the second unit data in each second unit data packet by using its own private key, to obtain third signature data corresponding to each second unit data packet. Specifically, taking the server as a bank server as an example, the server uses its own private key to sign The name refers to the bank server obtaining the corresponding private key according to the issuing bank identifier and the bank certificate serial number, and signing with the private key. The server sends the at least one second unit data packet carrying the third signature data to the first electronic signature device. Receiving, by the second electronic signature device, the at least one second unit data packet carrying the third signature data from the first electronic signature device, when the second electronic signature device performs the collection operation from the first electronic signature device, so as to facilitate the second electronic signature in the subsequent step. The device can use the server's public key to verify the authenticity of the second unit packet.

In another optional implementation manner of this embodiment, the transaction request sent by the second electronic signature device to the first electronic signature device further includes: a device identifier of the second electronic signature device; each second unit data packet is further The method includes: the fourth signature data obtained by the first electronic signature device by using the second unit data and the device identifier of the second electronic signature device. As an optional implementation manner, the first electronic signature device uses the private key of the first electronic signature to sign the second unit data and the device identifier of the second electronic signature device to obtain a fourth signature corresponding to each second unit data packet. data. Receiving, by the second electronic signature device, at least one second unit data packet carrying the fourth signature data from the first electronic signature device, when the second electronic signature device performs the collection operation from the first electronic signature device, so as to facilitate the second electronic signature device in the subsequent step. The correctness of the second unit data packet is verified using the public key of the first electronic signature device.

In this embodiment, after receiving the transaction request sent by the second electronic signature device, the first electronic signature device deducts the transaction amount requested by the second electronic signature device from the account balance of the second electronic signature device, and is the second electronic signature device. The sum of the issued currency face values is equal to at least one second unit data packet of the transaction amount, and after the second electronic signature device receives the second unit data packets, if the transfer is successful, the offline transaction is completed, and the second electronic signature device is completed. The first electronic signature device transfer (ie, receiving at least one second unit data packet sent by the first electronic signature device) may be received without networking with the server. The currency denomination value represented by each second unit data packet may be the same or different, and the number of the second unit data packet sent by the first electronic signature device to the second electronic signature device and the currency represented by each second unit data packet The face value may be determined by the first electronic signature device according to the transaction amount, or may be notified by the second electronic signature device according to the transaction amount, and then notified to the first electronic signature device, for example, as an optional implementation manner in this embodiment, the second The transaction request sent by the electronic signature device may also carry the type and number of the required second unit data packets. The first electronic signature device of the former can flexibly implement the delivery of the second unit data packet, and the latter can satisfy the requirement of the number of the second unit data packet and the face value of the user of the second electronic signature device.

For the case where the second electronic signature device determines the number of the second unit data packets according to the transaction amount and the currency denomination value represented by each second unit data packet, there is a possibility that the security chip of the first electronic signature device does not store the second The second unit data packet corresponding to the currency denomination requested by the electronic signature device or the number of stored data is insufficient. As an optional implementation manner in this embodiment, the first electronic signature device may be used to the second electronic signature device. Sending the prompt information, the prompt information may include: information that the second unit data packet of the corresponding currency denomination does not exist or the number of the data is insufficient, and the second electronic signature device may replace the currency denomination represented by the second electronic unit currency data packet according to the transaction amount. A combination strategy with the number, or a combination strategy of the currency denomination and the number represented by the second electronic unit currency data packet by the first electronic signature device according to the transaction amount. For example, the first electronic signature device receives the transaction request of the second electronic signature device to transfer 10 yuan, and requests to send 5 second unit data packets representing 2 yuan (hereinafter referred to as 2 yuan data packets), but the first electronic signature device If there are only 4 binary data packets, the message is sent to the second electronic signature device with only 4 binary data packets and the number of 2 metadata packets is insufficient. At this time, the second electronic signature device can replace the combination policy, for example, Returning, to the first electronic signature device, a response requesting to send 4 2-yuan data packets and 2 1--value data packets, or the first electronic signature device receiving the second electronic signature after transmitting the prompt information to the second electronic signature device The acknowledgment response of the device, the first electronic signature device may randomly determine a combination policy, for example, sending four 2-yuan data packets and two 1-yuan data packets to the second electronic signature device, thereby solving the first electronic One of the second unit data packets stored in the security chip of the signing device A problem with insufficient or non-existent.

In addition, in a specific implementation, there is also a problem that the currency denomination represented by the second unit data packet stored in the security chip of the first electronic signature device cannot piece together the at least one second unit data packet equal to the transaction amount, in order to To solve the problem, in an optional implementation manner of this embodiment, after the step S21, before the first electronic signature device acquires at least one second unit data packet from the security chip in the step S22, the embodiment provides The method further includes: the first electronic signature device sends the information to be changed, and the second electronic signature device receives the information to be changed, wherein the information to be changed is determined by the first electronic signature device according to the transaction amount and the number stored in the security chip. The currency denomination represented by the two-unit data packet determines, for example, the information to be changed may include a currency denomination that requires the second electronic signature device to return the change. If the second electronic signature device stores a second unit data packet representing the face value of the change coin currency, or the sum of the currency face values stored is equal to the second unit data packet for retrieving the change, the second electronic signature device may The first electronic signature device returns an acknowledgment response, that is, the first electronic signature device is notified that the second unit data packet for the change is stored, and the first electronic signature device receives the change information sent by the second electronic signature device (ie, returns a confirmation Correspondingly, the first electronic signature device acquires at least one second unit data packet from the security chip, wherein the sum of the currency denominations represented by the at least one second unit data packet is equal to the transaction amount plus the currency for retrieving the change face value.

For example, if the transaction amount is 7 yuan, the first electronic signature device cannot use the second unit data packet (hereinafter referred to as a 2-yuan data packet) respectively representing the denomination of the 2-yuan currency in the security chip of the first electronic signature device. The five 2-yuan data packages piece together the 7-yuan currency denomination, and the first electronic signature device can only use the five 2-yuan data packets stored in the security chip to piece together the currency face value that is closest to the transaction amount of 7 yuan and larger than the transaction amount. That is, the first electronic signature device can use the four 2-yuan data packets to piece together the 8-yuan currency denomination, and the second electronic signature device needs to retrieve 1 dollar change, that is, the first electronic signature device sends 4 2-yuan data packets to the first electronic signature device. After the second electronic signature device, the second electronic signature device needs to return a 1-yuan data packet (a second unit data packet representing a 1-yuan currency denomination) to the first electronic signature device. The first electronic signature device sends, to the second electronic signature device, the information to be changed that carries the change of change of 1 yuan, wherein the information to be changed is used to ask whether the second electronic signature device can retrieve the sum of the currency values represented by the second electronic signature device. The second unit packet is 1 yuan. If the security chip of the second electronic signature device stores the second unit data packet whose representative currency denomination sum is 1 yuan, sending the change information to the first electronic signature device, that is, agreeing to return the representative to the first electronic signature device The second unit data packet of 1 yuan or the sum of currency face values is 1 yuan. After receiving the change information, the first electronic signature device acquires four 2-yuan data packets from the security chip and sends them to the second electronic signature device, and the second electronic signature device returns to the first electronic signature device for 1 yuan. A packet (a second unit packet representing the face value of a currency). Therefore, when it is impossible to piece together the second unit data packet whose sum of the face value of the money represented is equal to the transaction amount, the electronic transaction can be completed through the zero change mechanism, making the electronic transaction more convenient.

In this embodiment, in order to prevent the electronic signature device from illegally reusing the same second unit data packet, the second unit data packet is confusing, and the uniqueness of the same second unit data packet in the payment process is ensured. The manner in which the first electronic signature device sends the at least one second unit data packet to the second electronic signature device includes at least one of the following two types:

method one:

In step S22, after the first electronic signature device transmits the at least one second unit data packet to the second electronic signature device, the first electronic signature device deletes the acquired at least one second unit data packet, because the first electronic signature After the device obtains the at least one second unit data packet according to the transaction amount and sends the data to the second electronic signature device, the local device data packet that has been sent remains in the local device, and the deletion action is not automatically performed. In this way, In order to ensure that the second electronic signature device can no longer reuse the second unit data, after the first electronic signature device sends the at least one second unit data packet to the second electronic signature device, the transmitted Two unit data packets, and the status word of the corresponding storage space is set to be unoccupied. Therefore, the first electronic signature device can delete the saved second unit data packet stored by the first electronic signature device after the second unit data packet is saved, thereby ensuring that the first electronic signature device cannot be reused and cannot be restored. The second unit data packet guarantees the uniqueness of the same second unit data packet in the payment process;

In the first mode, after receiving the at least one second unit data packet sent by the first electronic signature device, the second electronic signature device directly stores, because the first electronic signature device has deleted the at least one second unit data packet, The second unit data packet received by the second electronic signature device is unique, and duplicate data packets do not appear.

Method 2:

In step S22, the at least one second unit data packet sent by the first electronic signature device to the second electronic signature device is in a cipher text form, that is, the first electronic signature device sends the at least one second unit data packet to the second electronic signature. The device includes: the first electronic signature device encrypts the at least one second unit data, obtains at least one third unit data packet, and sends the at least one third unit data packet to the second electronic signature device; Receiving, by the signature device, the at least one second unit data packet sent by the first electronic signature device, the second electronic signature device receiving the at least one third unit data packet, and decrypting the at least one third unit data packet to obtain at least A second unit packet. For example, the second electronic signature device receives five third unit data packets representing two yuan from the first electronic signature device, and decrypts each third unit data packet representing two yuan to obtain five second units representing two yuan. data pack. The at least one third unit data packet received by the second electronic signature device includes a data ciphertext, wherein the data ciphertext is encrypted by the first electronic signature device for some or all of the data in each second unit data packet. of. Specifically, the second unit data packet may include: second unit data, third signature data, fourth signature data, a data packet identifier, and a device identifier of the second electronic signature device, where the first electronic signature device Encrypting part of the data in the two unit data packet means that the first electronic signature device encrypts at least the second unit data in the second unit data packet, for example, the first electronic signature device may be in the second unit data packet. The second unit data and the packet identifier are encrypted. In this embodiment, the encryption operation performed by the first electronic signature device on some or all of the data in each second unit data packet is an irreversible operation, that is, the first electronic signature device can encrypt the third unit data packet, but cannot Decrypting the third unit data packet from the third unit data packet, so that when the obtained at least one third unit data packet covers the corresponding at least one second unit data packet, only the encrypted content is stored in the first electronic signature device The third unit data packet cannot recover the second unit data packet because it cannot decrypt the third unit data packet, and the second unit data packet cannot be reused.

Specifically, as an optional implementation manner, the first electronic signature device encrypts the at least one second unit data, including: the first electronic signature device uses the public key of the second electronic signature device for at least each second unit Encrypting the second unit data in the data packet to obtain the data ciphertext; the second electronic signature device decrypting the at least one third unit data packet, including: the second electronic signature device using the private key of the second electronic signature device, at least for each The data ciphertext in the third unit data packet is decrypted. As another optional implementation manner, the first electronic signature device encrypts the at least one second unit data packet, including: the first electronic signature device utilizes a symmetric key associated with the second electronic signature device, at least for each The second unit data in the two unit data packet is encrypted to obtain the data ciphertext; the second electronic signature device decrypts the at least one third unit data packet, including: the second electronic signature device uses the first electronic signature device The symmetric key decrypts at least the data ciphertext in each third unit data packet.

For the foregoing optional implementation manner, the second electronic signature device may further include a public key of the second electronic signature device in the transaction request sent to the first electronic signature device, or the first electronic signature device may authenticate the platform to the third party. Obtaining a digital certificate of the second electronic signature device, where the public key of the second electronic signature device is stored in the digital certificate. Thereby, the first electronic signature device can acquire the public key of the second electronic signature device.

After the first electronic signature device encrypts the at least one second unit data packet, the method provided by the embodiment further includes: the first electronic signature device overwrites each second stored in the security chip with each third unit data packet. Unit data packet. In this embodiment, covering each second unit data packet stored in the security chip with each third unit data packet means that the first electronic signature device writes each generated third unit data packet into a corresponding original The storage space of the two-unit data packet replaces the original second unit data packet. For example, the second unit data packet with the data packet identified as 1*** is encrypted to generate a third unit data packet, and is written into the storage space corresponding to the 1***. Thus, after the second unit data packet device performs the second unit data packet payment, the security chip of the first electronic signature device stores only the second electronic signature device for the second unit data packet that has been sent to the second electronic signature device. The third unit data packet obtained by the public key is encrypted, and the first electronic signature device cannot have the private key of the second electronic signature device, so the first electronic signature device cannot decrypt the third unit data packet. The second unit data packet cannot be recovered, and the second unit data packet cannot be reused, the uniqueness of the same second unit data packet is guaranteed, and the third unit data packet is utilized by the second electronic signature device. The public key is encrypted, so the third unit data packet can only be decrypted by the second electronic signature device (only the second electronic signature device stores its own private key), so that only the payee (ie, the second electronic signature device) Can have and can use the unencrypted second unit data packet, even if other electronic signature devices illegally obtain the third unit data packet, because there is no The private key of the second electronic signature device cannot be decrypted and the acquired second unit data packet cannot be used, thereby ensuring the security of the second unit data packet circulation.

For the latter optional implementation, the symmetric key is negotiated by the first electronic signature device and the second electronic signature device, that is, the symmetric key used by the first electronic signature device in performing the encryption operation and the second The symmetric key used by the electronic signature device to perform the decryption operation is the same. After the first electronic signature device encrypts the at least one second unit data packet, the method provided by the embodiment further includes: the first electronic signature device overwrites each second stored in the security chip with each third unit data packet. Unit the packet and delete the symmetric key. In this embodiment, covering each second unit data packet stored in the security chip with each third unit data packet means that the first electronic signature device writes each generated third unit data packet into a corresponding original The storage space of the two-unit data packet replaces the original second unit data packet. For example, the second unit data packet with the data packet identified as 1*** is encrypted to generate a third unit data packet, and is written into the storage space corresponding to the 1***. In the manner of using the symmetric key encryption and decryption, if the first electronic signature device further has a symmetric key, the third unit data packet can be decrypted and restored to the second unit data packet. Therefore, in this embodiment, After the first electronic signature device sends the at least one second unit data packet to the second electronic signature device, the symmetric key must be forcibly deleted, whereby the first electronic signature device sends the second unit data packet after the second unit data packet payment Giving a second unit data packet of the second electronic signature device, the security chip of the first electronic signature device storing only the corresponding third unit data packet obtained by the second electronic signature device using the symmetric key encryption, and The signature device has deleted the symmetric key used for encryption. Therefore, the first electronic signature device can no longer decrypt the third unit data packet, and cannot recover the second unit data packet, and the second unit cannot be reused. The unit data packet guarantees the uniqueness of the same second unit data packet, and the symmetric key has only the first electronic signature And the second electronic signature device knows that, therefore, the third unit data packet can only be decrypted by the second electronic signature device, so that only the payee (ie, the second electronic signature device) can own and can use the unencrypted second Unit data packet, even if the other electronic signature device illegally acquires the third unit data packet, the second unit data packet cannot be obtained by decryption without the symmetric key, thereby ensuring the security of the second unit data packet circulation. Sex.

In this optional implementation manner, as an optional manner, the symmetric key may be an exclusive OR factor, and the exclusive OR factor may be a set of characters or numbers negotiated by the second electronic signature device and the first electronic signature device. a sequence for performing an exclusive OR operation; specifically, the first electronic signature device encrypts at least the second unit data in each second unit data packet by using a symmetric key associated with the second electronic signature device to obtain data The ciphertext includes: the first electronic signature device uses an exclusive OR factor to perform an exclusive OR operation on the second unit data in each second unit data packet to obtain a data ciphertext; and the second electronic signature device utilizes the first electronic signature The symmetric key associated with the device decrypts at least the data ciphertext in each second unit data packet, including: the second electronic signature device uses the XOR factor to perform at least the data ciphertext in each third unit data packet. Or operation. The XOR operation also belongs to a symmetric decryption operation mode, but the XOR operation is faster than other symmetric decryption operations. Therefore, the second electronic signature device can be modified to decrypt the third unit data packet. The efficiency of two unit packets.

In this embodiment, in step S22, at least the above manners can be prevented to prevent the electronic signature device from illegally reusing the same second unit data packet, thereby causing confusion in the circulation of the second unit data packet, and ensuring the same second unit data packet. Uniqueness in the payment process. Of course, this embodiment does not exclude other embodiments as long as the same technical effects can be achieved.

In addition, in the second mode, the third unit data packet is ciphertext, which ensures the security of the transmitted data, and even if intercepted by other devices, it is difficult to crack, further improving the security of the second unit data packet circulation. In addition, after the first electronic signature device receives the transaction request, in order to ensure the security of the transaction, the confirmation of the holding user of the first electronic signature device is also required to perform the subsequent transaction operation, which is optional in this embodiment. In an implementation manner, the transaction request sent by the second electronic signature device includes at least: a device identifier of the second electronic signature device. Before the first electronic signature device in step S22 acquires at least one second unit data packet from its security chip, the first electronic signature device prompts the holding user for the transaction amount and the device identifier of the second electronic signature device, and receives the Hold the user's confirmation message. In an optional implementation manner of the embodiment, the device identifier of the second electronic signature device may be a factory serial number of the second electronic signature device, or may be a device name of the second electronic signature device, or may be a second The electronic signature device holds the name of the user. Through the device identification, the holding user of the first electronic signature device can confirm whether the second electronic signature device is a transaction object agreed by the user, and the user selects to confirm the transaction only after the user approves the transaction amount and the transaction object. Thus, the security of the transaction is guaranteed by the user's confirmation of the transaction.

As an optional implementation manner, the first electronic signature device is provided with a display screen or a speaker, and displays the transaction amount and the device identifier of the second electronic signature device through the display screen set by itself or through the speaker voice set by itself; or The first electronic signature device establishes a connection with the external device, and prompts the holding user with the transaction amount and the device identifier of the second electronic signature device through the display screen or the speaker of the external device. This makes it easy for the user to confirm the payment amount and whether the payee is correct. As an optional implementation manner, the first electronic signature device may be provided with a confirmation button, and the user confirms by using the confirmation button. Certainly, the confirmation information input component may be further disposed on the first electronic signature device, and the confirmation information input component may specifically include: a PIN code input keyboard or a fingerprint input component. Therefore, the user can input the confirmation information by inputting the PIN code or the fingerprint, and while confirming the related information of the electronic transaction, the first electronic signature device can also verify the identity of the holding user, thereby further improving the electronic transaction. safety.

Step S23: The second electronic signature device receives the at least one second unit data packet, and verifies the third signature data in the at least one second unit data packet, and after the verification is passed, the at least one second unit data packet is Stored in a security chip.

In an optional implementation manner of this embodiment, the second electronic signature device is provided with a security chip, and the security chip has an independent processor and a storage list therein. The device can store the PKI digital certificate and the key, and other feature data, and perform encryption and decryption operations on the data to provide the user with data encryption and identity security authentication services. In this embodiment, the second electronic signature device can be used from the first electronic device. The second unit data packet received by the signature device or from another back-end server (such as a third-party server such as a bank server or a shopping mall recharge server) is stored in the security chip, because the data in the storage unit of the security chip cannot be illegally read. This ensures the security of the data stored in the storage unit.

Before the second electronic signature device in the step S23 stores the at least one second unit data packet in the security chip, the method provided in this embodiment further includes: the security chip allocation of the second electronic signature device is used to store the at least one The storage space of the second unit packet. In this embodiment, storing the at least one second unit data packet in the security chip in step S23, specifically: storing the at least one second unit data packet in a corresponding storage space, and corresponding storage space The status word is set to be occupied. Wherein, the security chip allocates one storage space for each second unit data packet, one storage space can only store one second unit data packet, and the transaction record of the second electronic signature device also records a transaction from other electronic The location of the storage space stored by each of the second unit data packets received by the signature device. The status word of the storage space is used to identify whether the storage space is already occupied, and if it is already occupied, the second electronic signature device cannot store the second unit data packet in the occupied storage space. When all the storage space allocated by the security chip is occupied, the second electronic signature device needs to perform an operation of requesting the background server to update the data packet or apply for a new storage space, wherein, as an optional implementation, the second electronic The signing device can request a new storage space to store the newly received second unit data packet. As another optional implementation manner, the second electronic signature device may further request to update the locally stored second unit data packet to the background server. For example, the second electronic signature device may request the background server to store the locally stored N (N). The second unit data packet representing the facet value is replaced by one or M (M<N) second unit data packets representing the face value of the large currency, as long as the stored currency amount is unchanged. Thus, a plurality of storage spaces can be released, thereby saving storage space to store newly received second unit data packets. In addition, in order to further improve the security of data storage, in this step, the second electronic signature device may further encrypt each second unit data packet to obtain ciphertext data of each second unit data packet, and each will be The ciphertext data is stored in the corresponding storage space. Thereby, it can be ensured that the second unit data packet stored in the storage space of the security chip cannot be maliciously copied or changed, thereby ensuring the security of storing the second unit data packet.

In this embodiment, in order to ensure the authenticity of the second unit data packet stored by the second electronic signature device in step S23, the second electronic signature device verifies the third signature data, and after the verification is passed, the at least one second The unit data packet is stored in the security chip. The third signature data is obtained by the server signing the second unit data, and each second unit data packet includes at least: the second unit data and the third signature data obtained by the server for signing the second unit data, thereby The second electronic signature device can verify the authenticity of the second unit data packet. As an optional implementation manner, the third signature data is signature data obtained by the server by using the private key of the server to sign the second unit data. Correspondingly, the verifying the third signature data by the second electronic signature device comprises: the second electronic signature device performing the verification of the third signature data by using the public key of the server. Therefore, the second electronic signature device uses the public key of the bank to perform the verification of the third signature data carried in the second unit data packet, so that the authenticity of the second unit data packet can be verified.

Further, the second electronic signature device further confirms whether the received second unit data packet is sent by the first first electronic signature device and is first, on the premise of ensuring that the received second unit data packet is authentic. Whether the object sent by the electronic signature device is indeed the second electronic signature device itself to avoid storing the data packet that is sent by the first electronic signature device, and the second electronic signature device in step S23 performs the at least one second unit data packet. Before being stored in the security chip, the transaction method further includes: the second electronic signature device verifies the fourth signature data, and after performing the verification, executing the step of storing the at least one second unit data packet The steps stored in the security chip. The fourth signature data is obtained by the first electronic signature device signing the second unit data and the device identifier of the second electronic signature device. Therefore, in an optional implementation manner of the embodiment, the second electronic signature device The transaction request sent to the first electronic signature device further includes: a device identifier of the second electronic signature device; each second unit data packet sent by the first electronic signature device to the second electronic signature device includes: at least: second unit data And obtaining, by the first electronic signature device, the fourth signature data obtained by signing the second unit data and the device identifier of the second electronic signature device, thereby enabling the second electronic signature device to verify the authenticity and correctness of the second unit data packet. As an optional implementation manner, the fourth signature data is signature data obtained by the first electronic signature device by using the private key of the first electronic unit to sign the device identifier of the second unit data and the second electronic signature device, that is, each The signature object of the fourth signature data is a combination of each of the second unit data and the device identifier of the second electronic signature device. Correspondingly, the verifying, by the second electronic signature device, the fourth signature data comprises: performing, by the second electronic signature device, each fourth signature data by using a public key of the first electronic signature device. The second electronic signature device may acquire the digital certificate of the first electronic signature device from the first electronic signature device, and obtain the public key of the first electronic signature device from the digital certificate. Of course, the second electronic signature device may also pre-store the digital certificate of the first electronic signature device and the other electronic signature device, and obtain the device identifier of the first electronic signature device from the first electronic signature device, and obtain the first pre-stored according to the device identifier. A digital certificate of the electronic signature device, from which the public key of the first electronic signature device is obtained. Therefore, the second electronic signature device uses the public key of the first electronic signature device to perform the verification of the fourth signature data carried in the second unit data packet, and can prove that the second unit data packet is actually sent by the first electronic signature device. For the second electronic signature device, the correctness of the second unit data packet is verified.

In order to facilitate the second electronic signature device to verify whether the at least one second unit data packet received from the first electronic signature device is the playback data, in the embodiment, the second unit data packet further includes: a data packet identifier.

As an optional implementation manner, the transaction request sent by the second electronic signature device to the first electronic signature device further includes: a data packet identifier. In a case where the first electronic signature device transmits at least one second unit data packet or the third unit data packet to the second electronic signature device one by one, the first electronic signature device may add the data packet identifier in the transaction request to one of the first Two unit data packets or one third unit data packet and sent to the second electronic signature device; the first electronic signature device sends at least one second unit data packet or the third unit data packet together to the second electronic signature In the case of the device, the first electronic signature device may add the data packet identifier in the transaction request to all the second unit data packets or the third unit data packet corresponding to the transaction amount and send it to the second electronic signature device, specifically The first electronic signature device adds the corresponding data packet identifier to the second unit data packet, and then sends the second unit data packet or the third unit data packet generated by the second unit data packet to the second The electronic signature device receives the third unit data packet by the second electronic signature device. In this embodiment, in order to prevent the second electronic data packet from being repeatedly received, the second electronic signature device storing the at least one second unit data packet in the security chip in the step S23 includes: the second electronic signature device Determining whether the data packet identifier in the received second unit data packet is the same as the data packet identifier in the sent transaction request, and if not, the second electronic signature device discards the second unit data packet with different data packet identifiers If they are the same, the second electronic signature device stores the second unit data packet with the same data packet identifier in the security chip. Thereby, it can be convenient for the second electronic signature device to check whether the received second unit data packet (ie, the second unit data packet obtained after decrypting the third unit data packet) is the playback data, and because the data packet The identifier is allocated by the second electronic signature device, so the second electronic signature device can determine whether the second unit data packet corresponding to the entire data packet identifier has been received, which is convenient for determining whether to initiate the retransmission request in the subsequent step. To prevent the replay attack, for example, when the data packet is identified as the random number R1 generated by the second electronic signature device, the first electronic signature device obtains the data packet identifier from the second electronic signature device before transmitting the second unit data packet. , that is, the random number R1, and send the second unit data packet including the random number R1 to the second electronic signature Name device. The second electronic signature device may check whether the received data packet identifier carried in the second unit data packet is a random number R1, and if yes, consider that the received second unit data packet is legal; otherwise, the received If the two-unit data packet is for playback data, the data is discarded. Thereby, it is possible to prevent the second electronic signature device from being attacked by the playback.

As another optional implementation manner, the transaction request sent by the second electronic signature device to the first electronic signature device further includes: a data packet identifier start value. Specifically, in an optional implementation manner of this embodiment, the second electronic signature device is provided with a counter. Before the step S21, the method provided by the embodiment further includes: the second electronic signature device uses the counter value of the counter to obtain The data packet identifier start value, that is, the value of the counter is the packet identifier start value, and the data packet identifier start value is obtained according to the number of data packets received by the second electronic signature device each time; After the step S23, the method provided by the embodiment further includes: the counter of the second electronic signature device calculates the data packet identifier start value plus the total number of the received second unit data packet to obtain a new data packet identifier. Starting value. Thus, the second electronic signature device can calculate and update the packet identification start value. The first electronic signature device may identify the data packet identifier corresponding to each second unit data packet according to the data packet identifier starting value and according to the total number of second unit data packets to be sent to the second electronic signature device. In this embodiment, in order to prevent the second electronic data packet from being repeatedly received, the second electronic signature device in step S23 stores the at least one second unit data packet in the security chip, including: the second electronic signature. The device determines whether the data packet identifier included in each second unit data packet satisfies a preset range determined according to the start value of the data packet identifier, and if not, the second electronic signature device determines that the data packet identifier does not satisfy the preset range. The second unit data packet is discarded. If yes, the second electronic signature device stores the second unit data packet whose data packet identifier meets the preset range in the security chip.

As an optional implementation manner, when the counter in the second electronic signature device is an incremental counter, the identifier of the data packet included in each second unit data packet should be not less than the start value of the data packet identifier, otherwise In order to replay data, wherein the incremental counter means that each time a second unit data packet is received by the second electronic signature device, the counter value of the counter is incremented by one.

For example, when the transaction amount is 8 yuan, the first electronic signature device needs to send three second unit data packets to the second electronic signature device, and the three second unit data packets respectively represent the currency face value of 1 yuan, 2 yuan, and 5 yuan. The data packet identification starting value obtained by the first electronic signature device from the second electronic signature device is 30, and the data packet identification start value may be the number of current data packets obtained by the counter counting of the second electronic signature device plus one. For example, before initiating the transaction, the second electronic signature device stores a total of 29 second unit data packets, and the packet identification of the 29 second unit data packets can be from 1 to 29, then, the received A data packet can be identified from 30, and the first electronic signature device calculates based on the packet identifier start value 30: the data packet identifier corresponding to the second unit data packet representing the 1-yuan currency denomination is 30, representing 2 The data packet identifier corresponding to the second unit data packet of the face value of the currency currency is 31, and the data packet identifier corresponding to the second unit data packet representing the face value of the three currency currency is 32. In this embodiment, the second electronic signature device is receiving After the three second unit data packets are stored, the associated data is stored according to the corresponding data packet identifier, and the original data packet identifier starting value 30 plus 3 is calculated to obtain a new data packet identifier start. 33. Therefore, the first electronic signature device only needs to acquire a data packet identifier starting value from the second electronic signature device, and can flexibly calculate each according to the number of second unit data packets to be sent to the second electronic signature device. The packet identifier corresponding to the second unit data packet. The second electronic signature device determines that the received data identifier of the three second unit data packets is not less than the data packet identifier start value 30, and stores the received three second unit data packets in the security chip. Of course, in this embodiment, only the counter set by the second electronic signature is an incremental counter. Other types of counters (such as a down counter) are also within the protection scope of the present invention, and are not illustrated herein. Therefore, the second electronic signature device can determine, according to the data packet identifier, whether the received second unit data packet is playback data, thereby preventing the second electronic signature device from being Replay attack.

After the step S23, if the second electronic signature device does not receive all the second unit data packets corresponding to the requested transaction amount, in an optional implementation manner of the embodiment, the method provided in this embodiment further includes: The second electronic signature device calculates the sum of the currency face values represented by the received second unit data packet and the transaction request according to the received number of the second unit data packets and the currency face value represented by each second unit data packet. Whether the transaction amount is consistent, if not, sending a retransmission request to the first electronic signature device; the first electronic signature device receives the retransmission request, and sends the retransmission information to the second electronic signature device according to the retransmission request, wherein And the retransmission request includes at least a device identifier of the second electronic signature device and/or a data packet identifier corresponding to each second unit data packet, so that the first electronic signature device can determine retransmission information according to the retransmission request, The sending information is selected by the first electronic signature device from a third unit data packet corresponding to a transaction of the second electronic signature device. All or part of the data packet to ensure that the second electronic signature device gets all the second unit data packets of a transaction.

In this embodiment, as an optional implementation manner, the second electronic signature device receives the retransmission information sent by the first electronic signature device according to the retransmission request, where the retransmission information includes at least one second unit data packet. The second electronic signature device deletes at least one second unit data packet previously stored in the security chip, and re-stores at least one second unit data packet retransmitted by the first electronic signature device. As another optional implementation manner, the second electronic signature device receives the retransmission information sent by the first electronic signature device according to the retransmission request, where the retransmission information includes the second unit data that is not received by the second electronic signature device. package. The second electronic signature device stores the unreceived second unit data packet in the security chip. It should be noted that the second unit data packet in the retransmission information can be understood as a cipher text form, that is, the third unit data packet obtained by the first electronic signature device for encrypting the second unit data packet, and therefore, in an optional manner In the implementation manner, the third unit data packet is actually included in the retransmission information, and the second electronic signature device receives the retransmission information (the third unit data packet) sent by the first electronic signature device, and then the third unit data. The packet decryption gets the second unit packet re-storage.

For the former, the resend request of the second electronic signature device includes at least the device identifier of the second electronic signature device, and the retransmission information of the first electronic signature device includes at least one second unit data packet, that is, a transaction that resends a transaction. All the second unit data packets corresponding to the amount, as an optional manner, the first electronic signature device may send the at least one second unit data packet to the second electronic signature device in cipher text, that is, at least one third The unit data packet is sent to the second electronic signature device. It can be understood that the retransmission information herein includes at least one third unit data packet, and the second electronic signature device deletes at least one second unit data packet previously stored in the security chip. And re-storing at least one second unit data packet retransmitted by the first electronic signature device (the second unit data packet obtained by decrypting the third unit data packet); for the latter, at least the second electronic signature device resending the request The method includes: a packet identifier of the second unit data packet that is not received, and may further include: a device identifier of the second electronic signature device The retransmission information of the first electronic signature device includes a second unit data packet that is not received by the second electronic signature device, that is, a second unit data packet indicated by the data packet identifier in the retransmission request, as an optional manner, An electronic signature device may send the second unit data packet indicated by the data packet identifier to the second electronic signature device in a cipher text format, that is, the third unit data packet indicated by the data packet identifier is sent to the second electronic signature device, where It is understood that the retransmission information herein includes a third unit data packet indicated by the data packet identifier, and the second electronic signature device stores the second unit data packet obtained by decrypting the third unit data packet indicated by the received data packet identifier in security. In the chip.

For the former, for example, for a transaction numbered 1*******, the transaction amount in the transaction request of the second electronic signature device is 10 yuan, and the first electronic signature device is to the second electronic signature device. Sending 5 second unit data packets respectively representing the denomination of the 2 yuan currency, but due to data loss during transmission, the second electronic signature device only receives 4 second unit data packets respectively representing the denomination of the 2 yuan currency, and the sum of the currency denominations It is 8 yuan, which is not equal to the transaction amount of 10 yuan. For In the transaction, the second electronic signature device sends a retransmission request to the first electronic signature device, where the retransmission request carries at least the device identifier of the second electronic signature device, and the first electronic signature device receives the second electronic signature device. After the resend request, the transaction for the second electronic signature device may query all corresponding third unit data packets, and carry the 5 third unit data packets in the retransmission information and send to the second electronic signature device. That is, the second unit data packet respectively representing the denomination of the 2-yuan currency is carried in the form of ciphertext and the retransmission information is transmitted to the second electronic signature device. Receiving the retransmission information, the second electronic signature device decrypts the five third unit data packets carried in the retransmission information to obtain five corresponding second unit data packets, and stores the four previously stored in the security chip. The second unit data packet representing the denomination of the 2-yuan currency is deleted, and the 5 second unit data packets obtained by the decryption are re-stored. Thereby, the second electronic signature device has the function of transmitting a retransmission request to the first electronic signature device when all second unit data packets required for the electronic transaction are not received, the first electronic signature device having the response second electronic signature device The function of resending, thereby ensuring that the second electronic signature device can receive all the second unit data packets required for the electronic transaction, and ensure that the transaction can be successfully completed.

For the latter, for example, for a transaction numbered 1*******, the transaction amount in the transaction request of the second electronic signature device is 5 yuan, and the second electronic signature device receives the first electronic signature The second unit data packet (referred to as a 2-ary data packet) representing the denomination of the 2-yuan currency, and the second unit data packet (referred to as the 1-ary data packet) representing the denomination of the 1-yuan currency, respectively, but transmitted by the device In the process, the data is lost. The second electronic signature device only receives two 2-yuan data packets, and the sum of the currency face values is 4 yuan, which is not equal to the transaction amount of 5 yuan. For the transaction, the second electronic signature device sends a retransmission request to the first electronic signature device, where the retransmission request carries at least the device identifier of the second electronic signature device and the data packet identifier of the unreceived data packet (ie, a data packet identifier of the 1st data packet or a data packet identifier of the received 2 metadata packet, after the first electronic signature device receives the retransmission request sent by the second electronic signature device, the second electronic signature device The pen transaction may query the corresponding third unit data packet according to the data packet identifier of the 1 yuan data packet, or determine the corresponding data packet identifier of the untransferred 1 metadata packet according to the data packet identifier of the 4 binary data packets. The third unit data packet carries the third unit data packet corresponding to the one-dimensional data packet identifier, and the retransmission information is sent to the second electronic signature device, that is, the second unit data packet corresponding to the data packet identifier is carried in the form of ciphertext. The sending information is sent to the second electronic signature device. Receiving the retransmission information, the second electronic signature device decrypts the third unit data packet corresponding to the one-dimensional data packet identifier carried in the retransmission information, and obtains a second unit data packet corresponding to the one-dimensional data packet identifier, and the The second unit data packet corresponding to the one-dimensional data packet identifier is stored in the security chip. Thereby, the second electronic signature device has a function of transmitting a retransmission request to the first electronic signature device when all second unit data packets required for the electronic transaction are not received, and receiving a second retransmission by the first electronic signature device The second unit data packet not received by the electronic signature device reduces the transmission amount of the retransmitted data, and ensures that the second electronic signature device can receive all the second unit data packets required for the electronic transaction.

In an optional implementation manner of this embodiment, the security chip of the first electronic signature device allocates a storage space for storing at least one third unit data packet (or a second unit data packet), and at least one third unit The data packet is stored in the corresponding storage space. The storage space of the security chip may store at least one second unit data packet, so that the first electronic signature device obtains the second unit data packet required for the transaction amount from the security chip after receiving the transaction request of the second electronic signature device. In addition, after encrypting the at least one second unit data packet to obtain at least one third unit data packet, after the at least one third unit data packet covers at least one second unit data packet, the at least one third unit data packet is stored in the corresponding In the storage space. After the first electronic signature device sends the retransmission information to the second electronic signature device according to the retransmission request, the first electronic signature device receives the confirmation information that the second electronic signature device returns the success of the reception, and the first electronic signature device will The status word storing the storage space of the at least one third unit data packet is modified to complete the transaction, or the storage space is cleared, and the status word of the corresponding storage space is modified to be unoccupied. Among them, the status word is the storage space where the transaction is completed, and can be overwritten by new data. Thereby, the first electronic signature device confirms the second electronic signature After receiving all the second unit data packets required for the electronic transaction, the name device can clear the storage space of the security chip, so as to release more storage space and ensure the subsequent transactions proceed smoothly.

In this embodiment, the storage space of the second electronic signature device is limited, and therefore, the remaining space of the second electronic signature device needs to be monitored at any time, so as to release the storage space in an instant, and avoid unnecessary transactions in the transaction process. The problem of failure. In an optional implementation manner of this embodiment, the remaining storage space of the second electronic signature device may also be monitored in real time by using a counter in the second electronic signature device. Specifically, after each transaction ends, that is, after step S23, the second electronic signature device uses the count value of the counter to obtain the total number of currently stored second unit data packets. Specifically, in each transaction, the counter adds the number of second unit data packets received by the transaction. After multiple transactions, the counter's count value is accumulated to a value when the value reaches a preset value. When the storage space of the second electronic signature device has been allocated, there is no unnecessary storage space. At this time, the second electronic signature device needs to perform an operation of requesting the server to update the data packet or apply for a new storage space (as described above). . In this embodiment, each storage space has the same size, and each second unit data packet has the same size and matches the size of the storage space, for example, the second electronic signature device allocates storage for a second unit data packet. The size of the space is 2M, the 2M storage space can store a second unit data packet, and the space reserved by a security chip for storing the second unit data packet is 1G, then the second electronic signature device can store up to 512 The two-unit data packet, that is, the preset value can be set to 512. Thereby, the remaining space of the second electronic signature device can be monitored in real time, and the redundant storage space is released in time, thereby avoiding the problem that the transaction fails if there is no extra space in the transaction process. Of course, the second electronic signature device can also use the count value of the counter to obtain the total number of second unit data packets of each currency denomination stored in the security chip. Thus, the second electronic signature device can obtain the total amount of money of the currently stored second unit data packet according to the currency face value and the number of the money represented by each stored second unit data packet.

In an optional implementation manner of this embodiment, after transmitting the at least one second unit data packet to the second electronic signature device, the first electronic signature device subtracts the transaction amount from the account amount to obtain the current account balance, and Displaying the transaction amount and/or the current account balance to the holding user; after storing the at least one second unit data packet in the security chip, the second electronic signature device adds the current account amount to the transaction amount to obtain the current account balance, Display the transaction amount and/or current account balance to the holding user. Thus, the user holding the electronic signature device can query the transaction amount and the current account balance on his own device.

With the transaction method of the electronic signature device provided by the embodiment, the user's funds are stored in the first electronic signature device or the second electronic signature device in the form of at least one second unit data packet. When the payee user (the second electronic signature device side) receives the second unit data packet, since the funds are no longer stored in the second electronic signature device in the form of numerical values, the second electronic signature device does not need to be changed by the server. The stored value, the second electronic signature device of the payee user only needs to receive a certain number of second unit data packets from the first electronic signature device of the payer user, whereby the electronic signature device is signed with other electronic When the device conducts electronic transactions, it no longer needs to rely on the server for online payment, and the server does not need to supervise the electronic signature device of the payee user or the payer user, thereby realizing offline electronic transactions. In addition, the second electronic signature device may receive the third unit data packet in the cipher text form from the first electronic signature device, further improving the security of the electronic transaction; further, adding the data packet identifier and the second in the second unit data packet The device identifier of the electronic signature device can effectively prevent the second electronic signature device from being attacked by the playback, and can facilitate the first electronic signature device to determine the retransmission information.

Any process or method description in the flowcharts or otherwise described herein may be understood to represent a module, segment or portion of code that includes one or more executable instructions for implementing the steps of a particular logical function or process. And the scope of the preferred embodiments of the invention includes additional implementations, in which the functions may be performed in a substantially simultaneous manner or in an opposite order depending on the functions involved, in the order shown or discussed. It will be understood by those skilled in the art to which the embodiments of the present invention pertain.

It should be understood that portions of the invention may be implemented in hardware, software, firmware or a combination thereof. In the above-described embodiments, multiple steps or methods may be implemented in software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented by any one or combination of the following techniques well known in the art: having logic gates for implementing logic functions on data signals. Discrete logic circuits, application specific integrated circuits with suitable combinational logic gates, programmable gate arrays (PGAs), field programmable gate arrays (FPGAs), etc.

One of ordinary skill in the art can understand that all or part of the steps carried by the method of implementing the above embodiments can be completed by a program to instruct related hardware, and the program can be stored in a computer readable storage medium. When executed, one or a combination of the steps of the method embodiments is included.

In addition, each functional unit in each embodiment of the present invention may be integrated into one processing module, or each unit may exist physically separately, or two or more units may be integrated into one module. The above integrated modules can be implemented in the form of hardware or in the form of software functional modules. The integrated modules, if implemented in the form of software functional modules and sold or used as stand-alone products, may also be stored in a computer readable storage medium.

The above mentioned storage medium may be a read only memory, a magnetic disk or an optical disk or the like.

In the description of the present specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" and the like means a specific feature described in connection with the embodiment or example. A structure, material or feature is included in at least one embodiment or example of the invention. In the present specification, the schematic representation of the above terms does not necessarily mean the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples.

Although the embodiments of the present invention have been shown and described, it is understood that the foregoing embodiments are illustrative and not restrictive Variations, modifications, alterations and variations of the above-described embodiments are possible within the scope of the invention. The scope of the invention is defined by the appended claims and their equivalents.

Claims

A method for trading an electronic signature device, comprising:

The electronic signature device sends a transaction request to the server, wherein the transaction request includes at least: a transaction amount;

Receiving, by the server, the transaction request, deducting the transaction amount from a bank account of the electronic signature device, acquiring at least one first unit data packet, and transmitting the at least one first unit data packet to the electronic signature device;

Wherein each first unit data packet represents one of a plurality of currency denominations, and each of the first unit data packets includes at least: first unit data, and the server signs the first unit data The first signature data, the sum of the currency denominations represented by the at least one first unit data packet is equal to the transaction amount;

Receiving, by the electronic signature device, the at least one first unit data packet, verifying the first signature data in the at least one first unit data packet, and after the verification is passed, the at least one first unit data packet Stored in a security chip.
The transaction method according to claim 1, wherein

The transaction request further includes: a device identifier of the electronic signature device;

Each of the first unit data packets further includes: second signature data obtained by the server from the first unit data and the device identifier of the electronic signature device;

Before the electronic signature device stores the at least one first unit data packet in the security chip, the method further includes:

The electronic signature device verifies the second signature data, and after the verification is passed, performs the step of the electronic signature device storing the at least one first unit data packet in the security chip.
The transaction method according to claim 1 or 2, wherein after the electronic signature device stores the at least one first unit data packet in a security chip, the method further includes:

The electronic signature device calculates, according to the received number of the at least one first unit data packet and the currency face value represented by each of the first unit data packets, a currency face value represented by the received first unit data packet. Whether the sum of the transactions is consistent with the transaction amount in the transaction request, and if not, sends a resend request to the server;

The server receives the resend request.
The method of claim 3, wherein after the server receives the resend request, the method further comprises:

Sending, by the server, retransmission information to the electronic signature device according to the retransmission request, where the retransmission information includes the at least one first unit data packet;

Receiving, by the electronic signature device, the retransmission information, deleting the at least one first unit data packet previously stored in the security chip, and re-storing the at least one first unit data resent by the server package.
The method of claim 3, wherein after the server receives the resend request, the method further comprises:

Sending, by the server, retransmission information to the electronic signature device according to the retransmission request, where the retransmission information includes a first unit data packet that is not received by the electronic signature device;

The electronic signature device stores the unreceived first unit data packet in the security chip.
The transaction method according to any one of claims 1 to 5, wherein before the electronic signature device stores the at least one first unit data packet in a security chip, the method further includes:

The electronic signature device allocates, by its security chip, a storage space for storing the at least one first unit data packet;

The electronic signature device stores the at least one first unit data packet in a security chip, including:

The electronic signature device stores the at least one first unit data packet in the corresponding storage space, and sets the status word of the corresponding storage space to be occupied.
A transaction method according to any one of claims 1 to 6, wherein

The first unit data includes at least: currency denomination data, or currency serial number and currency denomination data;

The first unit data packet further includes at least one of the following: an issuing bank identifier and a bank certificate serial number.
A method for trading an electronic signature device, characterized in that the transaction method comprises:

The second electronic signature device sends the transaction request to the first electronic signature device, wherein the transaction request includes at least: a transaction amount;

Receiving, by the first electronic signature device, the transaction request, and acquiring at least one second unit data packet from the security chip, and transmitting the at least one second unit data packet to the second electronic signature device, where Each second unit data packet represents one of a plurality of currency denominations, and each of the second unit data packets includes at least: second unit data, a third signature obtained by the server to sign the second unit data signature Data, the sum of the currency denominations represented by the at least one second unit data packet is equal to the transaction amount;

Receiving, by the second electronic signature device, the at least one second unit data packet, verifying the third signature data in the at least one second unit data packet, and after the verification is passed, the at least one second unit The data packet is stored in a security chip.
The method of claim 8, wherein after the first electronic signature device sends the at least one second unit data packet to the second electronic signature device, the method further comprises:

The first electronic signature device deletes the acquired at least one second unit data packet.
A transaction method according to claim 8 or 9, wherein

The transaction request includes at least: a device identifier of the second electronic signature device;
The transaction method according to claim 10, characterized in that

Each of the second unit data packets further includes: fourth signature data obtained by the first electronic signature device signing the second unit data and the device identifier of the second electronic signature;

Before the second electronic signature device stores the at least one second unit data packet in the security chip, the method further includes:

The second electronic signature device verifies the fourth signature data, and after the verification is passed, executing the second electronic signature device to the at least one second The step of storing the unit data packet in the security chip.
The transaction method according to claim 10, characterized in that

Each of the third unit data packets further includes: a device identifier of the second electronic signature device.
A transaction method according to any one of claims 8 to 12, characterized in that

The second unit data packet includes: a data packet identifier.
The transaction method according to claim 13, wherein

The transaction request further includes: a data packet identifier;

The second electronic signature device stores the at least one second unit data packet in the security chip, including:

Determining, by the second electronic signature device, whether the data packet identifier in the received second unit data packet is the same as the data packet identifier in the sent transaction request, and if not identical, identifying the second unit data that is different from the data packet identifier The packet is discarded. If they are the same, the second unit data packet with the same packet identifier is stored in the security chip.
The transaction method according to claim 13, wherein

The transaction request further includes: a data packet identification start value;

The second electronic signature device stores the at least one second unit data packet in the security chip, including:

The second electronic signature device determines whether the data packet identifier included in each second unit data packet satisfies a preset range determined according to the data packet identifier start value, and if not, the data packet identifier is not The second unit data packet that satisfies the preset range is discarded, and if so, the second unit data packet whose data packet identifier meets the preset range is stored in the security chip.
The method of claim 15, wherein the method further comprises: before the second electronic signature device sends the transaction request to the first electronic signature device, the method further comprising:

The second electronic signature device uses the count value of the counter to obtain the data packet identification start value;

After the second electronic signature device stores the at least one second unit data packet in the security chip, the method further includes:

The counter of the second electronic signature device calculates a new packet identifier start value by adding the data packet identifier start value to the total number of the received second unit data packets.
The transaction method according to any one of claims 13 to 16, wherein after the second electronic signature device stores the at least one second unit data packet in the security chip, the method further includes:

The second electronic signature device calculates, according to the received number of the second unit data packets and the currency face value represented by each second unit data packet, a currency face value represented by the received second unit data packet. Whether the sum of the transactions is consistent with the transaction amount in the transaction request, and if not, sending a retransmission request to the first electronic signature device;

The first electronic signature device receives the retransmission request, and sends retransmission information to the second electronic signature device according to the retransmission request, where the retransmission request includes at least the second electronic The device identifier of the signature device and/or the packet identifier corresponding to each of the second unit data packets.
The method of claim 17, wherein after the first electronic signature device sends the resend information to the second electronic signature device according to the resend request, the method further includes:

Receiving, by the second electronic signature device, the retransmission information, wherein the retransmission information includes the at least one second unit data packet, and storing the at least one second unit previously stored in the security chip And deleting the data packet, and re-storing the at least one second unit data packet retransmitted by the first electronic signature device.
The method of claim 17, wherein after the first electronic signature device sends the resend information to the second electronic signature device according to the resend request, the method further includes:

Receiving, by the second electronic signature device, the retransmission information, where the retransmission information includes a second unit data packet that is not received by the second electronic signature device, and the second unit that is not received The data packet is stored in its security chip.
A transaction method according to any one of claims 9 to 19, characterized in that

The second unit data includes at least: currency denomination data, or currency serial number and currency denomination data;

The second unit data packet includes at least one of the following: an issuing bank identifier and a bank certificate serial number.
The transaction method according to any one of claims 9 to 20, wherein before the storing, by the second electronic signature device, the at least one second unit data packet in the security chip, the method further comprises:

The security chip of the second electronic signature device allocates a storage space for storing the at least one second unit data packet;

The second electronic signature device stores the at least one second unit data packet in the security chip, including:

The second electronic signature device stores the at least one second unit data packet in the corresponding storage space, and sets the status word of the corresponding storage space to be occupied.