Blockchain-based resource management system, method and computer device

Abstract

The application discloses a blockchain-based resource management system and method, a computer device and a storage medium, and belongs to the technical field of blockchains. A first node in the application is configured to store resource issuance information on a blockchain, and send the issuance information to a second node. The second node is configured to add a record signature to the issuance information of the registered resource, and send the signed issuance information to other nodes in the system, thereby completing the registration and issuance of the resource. A third node is configured to store resource share information on the blockchain based on the resource contract included in the issuance information, and for the executed resource subscription transaction. Through the above technical solution, each node involved in the resource transaction process can verify whether the resource has been registered based on the record signature, effectively ensuring the reliability of the resource. Based on the tamper-proof and decentralized characteristics of the blockchain, the credibility of the issuance information and the resource share information is effectively improved, thereby effectively improving the security of the resource transaction.

Description

Technical Field

[0001] This application relates to the field of blockchain technology, and in particular to a blockchain-based resource management system, method, computer device, and storage medium. Background Technology

[0002] Purchasing tradable resource products is one way to generate income. Resource issuing companies raise funds by issuing resource products that have been registered and filed with regulatory agencies. Investors subscribe to shares of the resource products issued by the resource issuing company, thus becoming resource holders. The custodian designated by the resource issuing company (usually a trusted institution with custodian qualifications) manages and uses the funds raised from the issuance of resource products to generate income for the investors.

[0003] The operational process of the aforementioned resource products involves multiple roles, including resource issuing companies, custodians, regulatory agencies, and resource holders. Resource-related information undergoes multiple transfers and verifications. Currently, the validity of resource-related information primarily relies on regulatory agencies, resulting in insufficient transparency in information flow. This leads to issues such as inaccurate registration information and unreliable custodians, significantly impacting the security of resource transactions. Summary of the Invention

[0004] This application provides a blockchain-based resource management system, method, computer equipment, and storage medium, which can effectively improve the security of resource transactions. The technical solution is as follows:

[0005] On the one hand, a blockchain-based resource management system is provided, which includes a first node, a second node, and a third node;

[0006] The first node is used to respond to a request for the issuance of a resource, store the issuance information of the resource on the blockchain, and send the issuance information of the resource to the second node. The issuance information includes the transaction account and resource contract corresponding to the resource, and the resource contract is used to execute the transaction process of the resource.

[0007] The second node is used to add a filing signature to the received issuance information, send the issuance information with the filing signature to other nodes in the system, and run the resource contract on the blockchain. The filing signature is used to verify whether the resource has been registered.

[0008] The third node is used to respond to the target object's share registration request for the resource, and store the target object's resource share information on the blockchain based on the resource contract included in the issuance information. The resource share information includes the target object's share of the resource. The share registration request is triggered when it is detected that the target object's resource subscription transaction has been executed.

[0009] On the one hand, a blockchain-based resource management method is provided, applied in a blockchain-based resource management system, which includes a first node, a second node, and a third node. The method includes:

[0010] In response to a resource issuance request, the first node stores the resource issuance information on the blockchain and sends the resource issuance information to the second node. The issuance information includes the transaction account and resource contract corresponding to the resource, and the resource contract is used to execute the transaction process of the resource.

[0011] The second node adds a filing signature to the received issuance information, sends the issuance information with the filing signature to other nodes in the system, and runs the resource contract on the blockchain. The filing signature is used to verify whether the resource has been registered.

[0012] In response to the target object's share registration request for the resource, the third node stores the target object's resource share information on the blockchain based on the resource contract included in the issuance information. The resource share information includes the target object's share of the resource. The share registration request is triggered when the target object's resource subscription transaction has been executed.

[0013] In one possible implementation, the response to a resource issuance request, storing the resource issuance information on the blockchain, and sending the resource issuance information to the second node includes:

[0014] In response to a request to issue the resource, an issuance signature is added to the issuance information of the resource, the issuance information with the issuance signature is stored on the blockchain, and the issuance information with the issuance signature is sent to the second node. The issuance signature is used to verify whether the issuance information has been changed.

[0015] In one possible implementation, the share registration request carries the target object's account address on the blockchain. In response to the target object's share registration request for the resource, based on the resource contract included in the issuance information, the storage of the target object's resource share information on the blockchain includes:

[0016] Based on the share registration request and the resource contract, the target entity's share of the resource is determined;

[0017] Based on the target object's share of the resource, a digital proof for trading the resource is generated, and the number of the digital proofs indicates the target object's share of the resource.

[0018] The digital proof is stored in the target object's account address on the blockchain.

[0019] In one possible implementation, the method further includes:

[0020] In response to a share transfer request initiated by the target object, the resource share information of the target object is updated on the blockchain based on the resource contract.

[0021] In one possible implementation, the share transfer request indicates the share to be transferred and the transferee, and the method further includes:

[0022] The digital proof of the target quantity corresponding to the transferred share is transferred from the target object's account address on the blockchain to the transfer object's account address on the blockchain.

[0023] In one possible implementation, the share registration request carries the subscription value corresponding to the resource subscription transaction. In response to the target object's share registration request for the resource, based on the resource contract included in the issuance information, the resource share information of the target object is stored on the blockchain, including:

[0024] In response to the share registration request, the share value of the resource is obtained from the trading account;

[0025] Based on the share value, the subscription value, and the resource contract, the resource share information of the target object is stored on the blockchain. The resource share information includes the target object's share of the resource and the value corresponding to the share.

[0026] In one possible implementation, the method further includes:

[0027] At each target period, the current share value of the resource is obtained from the transaction account and stored on the blockchain.

[0028] In one possible implementation, the method further includes:

[0029] In response to the third node storing the current share value of the resource on the blockchain, obtain the reference value of the resource;

[0030] If the current share value and the reference value are inconsistent, the transaction process for the resource shall be terminated.

[0031] In one possible implementation, the method further includes:

[0032] In response to a settlement request for the resource, the number of digital proofs on the blockchain used to trade the resource is determined, and the number of digital proofs stored by an account address on the blockchain indicates the share of the resource held by that account address.

[0033] The resource is settled based on the number of digital proofs. Once settlement is complete, the digital proofs stored at the account address on the blockchain are marked as settled.

[0034] In one possible implementation, settling accounts for the resource based on the amount of the digital proof includes:

[0035] In response to a settlement request for the resource, the final share of the resource's value is obtained from the transaction account;

[0036] The settlement value corresponding to the account address is determined based on the final share value and the number of digital proofs stored at the account address.

[0037] Based on the settlement value, the transaction account is instructed to transfer resources to the object corresponding to the account address.

[0038] On the one hand, a computer device is provided, which includes one or more processors and one or more memories, wherein at least one computer program is stored in the one or more memories, and the computer program is loaded and executed by the one or more processors to implement the above-described blockchain-based resource management method.

[0039] On the one hand, a computer-readable storage medium is provided, which stores at least one computer program that is loaded and executed by a processor to implement the above-described blockchain-based resource management method.

[0040] On the one hand, a computer program product or computer program is provided, which includes program code stored in a computer-readable storage medium. The processor of a computer device reads the program code from the computer-readable storage medium and executes the program code, causing the computer device to perform the aforementioned blockchain-based resource management method.

[0041] Through the above technical solutions, each node involved in the resource transaction process can verify whether the resource has been registered and filed based on the registration signature, effectively ensuring the reliability of the resource. Based on the immutability and decentralization of blockchain, the credibility and transparency of issuance information and resource share information are effectively improved, thereby effectively enhancing the security of resource transactions. Furthermore, registering the holding share of the resource as a digital proof that can circulate on the chain provides a blockchain-based secondary trading market, which greatly improves the liquidity of resources while ensuring the security of resource transactions. Attached Figure Description

[0042] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0043] Figure 1 This is a schematic diagram of the structure of a distributed system provided in an embodiment of this application;

[0044] Figure 2 This is a schematic diagram of a block structure provided in an embodiment of this application;

[0045] Figure 3 This is an architecture diagram of a blockchain-based resource management system provided in an embodiment of this application;

[0046] Figure 4 This is a flowchart illustrating a blockchain-based resource management method provided in an embodiment of this application;

[0047] Figure 5 This is an architecture diagram of another blockchain-based resource management system provided in the embodiments of this application;

[0048] Figure 6 This is a flowchart illustrating a blockchain-based resource management method provided in an embodiment of this application;

[0049] Figure 7 This is a schematic diagram of a resource management process provided in an embodiment of this application;

[0050] Figure 8 This is a schematic diagram of the structure of a computer device provided in an embodiment of this application. Detailed Implementation

[0051] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0052] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0053] In this application, the terms "first," "second," etc., are used to distinguish identical or similar items that have essentially the same function. It should be understood that there is no logical or temporal dependency between "first," "second," and "nth," nor does it limit the quantity or execution order. It should also be understood that although the following description uses the terms "first," "second," etc., to describe various elements, these elements should not be limited by the terms.

[0054] These terms are simply used to distinguish one element from another. For example, without departing from the various examples, a first node can be called a second node, and similarly, a second node can be called a first node. Both first and second nodes can be nodes, and in some cases, they can be separate and distinct nodes.

[0055] "At least one" refers to one or more nodes. For example, at least one node can be one node, two nodes, three nodes, or any integer number of nodes greater than or equal to one. "Multiple" refers to two or more nodes. For example, multiple nodes can be two nodes, three nodes, or any integer number of nodes greater than or equal to two.

[0056] It should be noted that all information (including but not limited to object device information, object personal information, etc.), data (including but not limited to data used for analysis, stored data, displayed data, etc.), and signals involved in this application have been authorized by the object or fully authorized by all parties, and the collection, use, and processing of related data must comply with the relevant laws, regulations, and standards of the relevant countries and regions. For example, the account addresses on the blockchain involved in this application were obtained with full authorization.

[0057] To facilitate understanding of the technical processes in the embodiments of this application, some terms involved in the embodiments of this application are explained below:

[0058] Blockchain is a novel application model of computer technologies such as distributed data storage, peer-to-peer transmission, consensus mechanisms, and cryptographic algorithms. Essentially, a blockchain is a decentralized database, a chain of data blocks linked together using cryptographic methods. Each data block contains information about a batch of network transactions, used to verify the validity of the information (anti-counterfeiting) and generate the next block. A blockchain can include an underlying platform, a platform product service layer, and an application service layer.

[0059] The underlying blockchain platform can include basic services and processing modules such as smart contracts. The basic service module is deployed on all blockchain node devices to verify the validity of business requests. After reaching a consensus on valid requests, it records them in storage. For a new business request, the basic service first performs interface adaptation parsing and authentication (interface adaptation), then encrypts the business information using a consensus algorithm (consensus management), and transmits it completely and consistently to the shared ledger (network communication) for recording and storage. The smart contract module is responsible for contract registration, issuance, triggering, and execution. Developers can define contract logic using a programming language and publish it to the blockchain (contract registration). According to the contract terms, execution is triggered by calling keys or other events to complete the contract logic. It also provides functions for contract upgrades and cancellations.

[0060] The platform's product service layer provides the basic capabilities and implementation frameworks for typical applications. Developers can leverage these basic capabilities, add business characteristics, and complete the blockchain implementation of business logic. The application service layer provides application services based on blockchain solutions for business users.

[0061] A consortium blockchain is a blockchain whose consensus process is controlled by pre-selected blockchain nodes. The blockchain ledger can restrict read access only to consortium members or provide read capabilities to external users. In a consortium blockchain, all or some functions are only open to the blockchain node members within the chain, and each blockchain node in the consortium blockchain can customize read / write permissions, query permissions, etc., as needed.

[0062] Consensus mechanism: A mathematical algorithm used in blockchain systems to establish trust and assign rights among different nodes. In a blockchain system, transactions can be verified and confirmed in a very short time through voting by specific nodes or all nodes. Specifically, if multiple nodes with unrelated interests can reach a consensus on a transaction, it can be assumed that all nodes in the system can also reach a consensus on it.

[0063] Smart contracts: Computer protocols designed to transmit, verify, or execute contracts in an informational manner. Smart contracts allow for trusted transactions without the need for a third party, and these transactions are traceable and irreversible.

[0064] The digital proof involved in this application is a replaceable, uniform, and divisible certificate of rights.

[0065] The blockchain-based resource management system described in this application can be a distributed system formed by multiple nodes (any form of computer device accessing the network, such as servers or terminals) and clients connected through network communication. See [link to relevant documentation]. Figure 1 , Figure 1 This is a schematic diagram of a distributed system provided in an embodiment of this application. The distributed system 100 consists of multiple nodes 101 (any form of computing device in the network, such as a server or terminal) and clients 102. The nodes form a peer-to-peer (P2P) network. The P2P protocol is an application layer protocol running on top of the Transmission Control Protocol (TCP). In the above-mentioned distributed system 100, any machine, such as a server or terminal, can join and become a node. A node includes a hardware layer, a middleware layer, an operating system layer, and an application layer.

[0066] See Figure 1 The functions of each node in the distributed system shown include:

[0067] 1) Routing: A basic function of nodes used to support communication between nodes.

[0068] 2) Applications are deployed in the blockchain to implement specific business needs. They record data related to the implementation of functions to form record data, carry digital signatures in the record data to indicate the source of the task data, and send the record data to other nodes in the blockchain system. When other nodes successfully verify the source and integrity of the record data, they add the record data to a temporary block.

[0069] For example, the business logic implemented by the application includes:

[0070] 2.1) Smart contracts are computerized protocols that can execute the terms of a contract. They are implemented through code deployed on a shared ledger that executes when certain conditions are met. Based on actual business needs, the code is used to complete automated transactions, such as querying the logistics status of goods purchased by a buyer and transferring the buyer's electronic money to the merchant's address after the buyer signs for the goods. Of course, smart contracts are not limited to executing contracts for transactions; they can also execute contracts for processing received information.

[0071] 2.2) Blockchain account, used to provide the function of recording transactions in the blockchain, that is, sending the transaction record of the current transaction to other nodes in the blockchain system. After the other nodes successfully verify it, as a response to acknowledge the validity of the transaction, they store the transaction record data in the temporary block of the blockchain.

[0072] 2.3) Shared ledger, used to provide functions such as storage, query and modification of ledger data. It sends the record data of the operation on the ledger data to other nodes in the blockchain system. After the other nodes verify the validity, as a response to acknowledge the validity of the ledger data, they store the record data in a temporary block. They can also send confirmation to the node that initiated the operation.

[0073] 3) A blockchain consists of a series of blocks linked together in chronological order of their creation. Once a new block is added to the blockchain, it cannot be removed. Each block records the data submitted by nodes within the blockchain system. See also... Figure 2 , Figure 2 This is a schematic diagram of a block structure provided in an embodiment of this application. Each block includes the hash value of the transaction records stored in this block (the hash value of this block) and the hash value of the previous block. The blocks are connected through their hash values ​​to form a blockchain. Additionally, each block may include information such as a timestamp when it was generated. Essentially, a blockchain is a decentralized database, a chain of data blocks linked together using cryptographic methods. Each data block contains relevant information used to verify the validity of the information (anti-counterfeiting) and to generate the next block.

[0074] Based on the above description of the distributed system 100, this application embodiment provides a blockchain-based resource management system. (See also...) Figure 3 , Figure 3 This is an architecture diagram of a blockchain-based resource management system provided in an embodiment of this application. The system includes a first node 310, a second node 320, and a third node 330.

[0075] The first node 310 provides issuance information storage services. It stores the issuance information of a resource on the blockchain and sends this information to the second node 320, thereby initiating the registration and filing process for the resource. The issuance information includes the corresponding trading account and resource contract. The trading account manages the funds involved in the resource, and the resource contract executes the transaction process. In some embodiments, the registration and filing refers to a trusted regulatory agency verifying and recording the authenticity and validity of the issuance information to confirm that the issuance of the resource complies with regulations.

[0076] In some embodiments, the resource is a financial service. Optionally, an object can become the holder of the resource by investing funds to subscribe for a specified share of the resource. This process is equivalent to the object providing funds to obtain the financial service, thereby obtaining the value gain or value loss brought about by the financial service.

[0077] The second node 320 is a blockchain node corresponding to a trusted regulatory agency, used to provide registration and filing services. This second node 320 can verify and record the authenticity and validity of the received resource issuance information. If it confirms that the resource issuance complies with regulations, it adds a filing signature to the issuance information, sends the signed issuance information to other nodes in the system, and runs the resource contract on the blockchain, thereby completing the resource issuance process. The filing signature is used to verify whether the resource has been registered and filed.

[0078] The third node 330 provides share registration services. In response to a target object's share registration request for the resource, the third node 330 stores the target object's share of the resource on the blockchain. This share registration request is triggered upon detecting that the target object's resource purchase transaction has been executed.

[0079] This application provides a blockchain-based resource management method that can be applied to the above-mentioned... Figure 3 The system provided. Figure 4 This is a flowchart illustrating a blockchain-based resource management method provided in an embodiment of this application. See also... Figure 4 The method includes the following steps 401 to 403.

[0080] 401. In response to a resource issuance request, the first node stores the resource issuance information on the blockchain and sends the resource issuance information to the second node.

[0081] This issuance information includes the trading account and resource contract corresponding to the resource. The resource contract is used to execute the trading process for the resource. See the description of this issuance information and the resource for reference. Figure 3 The corresponding content will not be elaborated here.

[0082] In this application embodiment, the resource is a fund operation service. The issuance information of the resource is used to describe the actual operation mode of the fund operation service. For example, the issuance information also includes the issuance cycle, issuance scale, lock-up period and fund operation strategy of the resource, etc. This application does not limit this.

[0083] In some embodiments, the first node sends the issuance information to other nodes that execute the blockchain consensus based on the issuance information. After the other nodes successfully verify the legitimacy of the source of the issuance information, that is, after the other nodes acknowledge the validity of the issuance information, the first node and the other nodes that execute the blockchain consensus store the issuance information as a block of the blockchain, thus completing the storage process of the issuance information on the blockchain.

[0084] In some embodiments, the first node sends the resource issuance information to the second node that executes the blockchain consensus during the process of storing the issuance information; in other embodiments, the first node sends the issuance information to the second node after the issuance information is successfully stored.

[0085] In some embodiments, the resource contract is a program running on the blockchain that provides the transaction rules to be followed by the parties to the resource transaction, such as the transaction permissions and responsibilities of the parties.

[0086] By using the above technical solutions, the issuance information of resources is stored on the blockchain. Based on the immutability and decentralization of the blockchain, the trustworthiness of the issuance information is effectively improved, thereby enhancing the security of transactions based on the resource.

[0087] 402. The second node adds a filing signature to the received issuance information, sends the issuance information with the filing signature to other nodes in the system, and runs the resource contract included in the issuance information on the blockchain. The filing signature is used to verify whether the resource has been registered.

[0088] The instructions for registration and filing are as follows (refer to the original text). Figure 3 The corresponding content will not be elaborated here.

[0089] In some embodiments, the filing signature is a digital signature issued by the regulatory authority corresponding to the second node. Optionally, the regulatory authority verifies and records the authenticity and validity of the resource issuance information. If the issuance of the resource is confirmed to comply with regulations, the regulatory authority executes a signature algorithm based on its private key to add a verifiable filing signature to the issuance information.

[0090] In some embodiments, the second node adds a filing signature to the issuance information based on the information determined upon successful registration and filing of the resource. For example, the second node can execute a signature algorithm based on the private key of the regulatory authority and the registration and filing code of the resource to add a filing signature to the issuance information. Optionally, the format of the registration and filing code can be: resource type code + resource registration authority code + resource issuance serial number.

[0091] In this embodiment of the application, the second node sends the issuance information with added filing signature to other nodes in the system, so that each node in the system can receive the issuance information with added filing signature, thereby ensuring the accuracy of the information.

[0092] 403. In response to the target object's share registration request for the resource, the third node stores the target object's resource share information on the blockchain based on the resource contract included in the issuance information. The resource share information includes the target object's share of the resource. The share registration request is triggered when the target object's resource subscription transaction has been executed.

[0093] The holding share is determined based on the value provided by the target entity in the resource subscription transaction and the total value corresponding to the resource. Optionally, the resource share information also includes the confirmation time of the holding share, which indicates the effective date when the target entity's ownership of the holding share becomes effective.

[0094] In some embodiments, the third node is used to manage the trading account of the resource, and the execution process of the resource subscription transaction includes: the target object providing funds to the trading account of the resource; the trading account receiving the funds provided by the target object and confirming that the resource subscription transaction has been executed; the third node detecting that the resource subscription transaction in the target trading account has been executed, and triggering the share registration request according to the amount of funds.

[0095] In some embodiments, the third node can, based on the issuance information received from the second node and after confirming that the resource has been registered and filed based on the filing signature of the issuance information, run the resource contract included in the issuance information, thereby determining the target object's share of the resource according to the transaction rules provided by the resource contract, and storing the target object's resource share information as a block in the blockchain.

[0096] Through the above technical solution, the resource transaction process is executed under the multi-node consensus management mechanism. Each node involved in the resource transaction process can verify whether the resource has been registered and filed based on the filing signature, which effectively ensures the authenticity and reliability of the resource. Furthermore, based on the immutability and decentralization of blockchain, the credibility of issuance information and resource share information is effectively improved, thereby effectively enhancing the security of resource transactions.

[0097] The technical solution of this application will be described in detail below through some embodiments. This application is based on the above. Figure 3 The provided blockchain-based resource management system offers another alternative blockchain-based resource management system. See also Figure 5 , Figure 5 This is an architecture diagram of another blockchain-based resource management system provided in this application embodiment. The system includes a first node 510, a second node 520, a third node 530, and a client 540.

[0098] The services provided by the first node 510, the second node 520, and the third node 530 are referenced. Figure 3 The corresponding content.

[0099] In this embodiment, the second node 520 includes a notarization and signing node 521 and a monitoring node 522. The notarization and signing node 521 performs the functions of the second node 320 described above, providing registration and filing services, which will not be elaborated upon here. In this embodiment, the monitoring node 522, in addition to providing the registration and filing services, provides monitoring services for on-chain resource transactions to ensure the accuracy and reliability of resource-related information stored on the blockchain. The implementation process of this monitoring service will be described in detail later and will not be repeated here.

[0100] In this embodiment, the third node 530 is a blockchain node corresponding to the resource trading platform, capable of accessing the trading account corresponding to the resource, thereby providing settlement services for the resource in addition to providing share registration services. This settlement service refers to distributing the funds corresponding to the resource to each shareholding entity based on the current value of the resource and their respective holding shares. The implementation process of this settlement service will be described in detail later and will not be repeated here. In some embodiments, the third node can also provide a value update service for the resource; the implementation process of this value update service will be described in detail later and will not be repeated here.

[0101] Specifically, client 540 is a lightweight client that provides objects with the functions of initiating resource purchase transactions and managing their holdings of resources. Optionally, client 540 is associated with the object's account in the blockchain and can interact with the blockchain based on the object's account address in the blockchain according to requests initiated by the object (such as transaction requests or query requests). Optionally, the functions of client 540 can refer to... Figure 1 The corresponding content includes an introduction to client 101.

[0102] Next, based on the above Figure 5 The provided system architecture, taking the interaction process between the first node 510, the second node 520, the third node 530 and the client 540 as an example, introduces the technical solution of the embodiment of this application. Figure 6 This is a flowchart illustrating a blockchain-based resource management method provided in an embodiment of this application. See also... Figure 6 The method includes the following steps 601 to 615.

[0103] 601. In response to a resource issuance request, the first node adds an issuance signature to the resource issuance information and stores the issuance information with the issuance signature on the blockchain. The issuance signature is used to verify whether the issuance information has been changed. The issuance information includes the transaction account and resource contract corresponding to the resource. The resource contract is used to execute the transaction process of the resource.

[0104] In this process, the first node adds an issuance signature to the issuance information to ensure that the issuance information is locked on the blockchain, meaning that the issuance information cannot be altered, thus guaranteeing the reliability and security of the information from the data source. In some embodiments, the first node executes a signature algorithm based on the private key of the resource issuing authority to add an issuance signature to the issuance information.

[0105] In some embodiments, the first node can perform integrity verification on the resource issuance information to improve the efficiency of subsequent registration and filing of resources.

[0106] In some embodiments, the first node compares the resource's issuance information with a preset issuance information template to determine the completeness of the resource's issuance information. The issuance information includes multiple fields, each carrying information of a corresponding type; for example, the transaction account field carries the transaction account number. The issuance information template includes key information fields that indicate crucial information related to the registration and filing process within the resource's issuance information, such as the transaction account number and the qualification certificate of the resource issuing institution.

[0107] In some embodiments, if the first node determines that the fields included in the issuance information match the key information fields, it determines the issuance information of the resource to have a first completeness, which indicates that the issuance information meets the basic requirements for initiating a registration and filing process. In other embodiments, if the first node determines that the fields included in the issuance information match the fields included in the issuance information template, it determines the completeness of the issuance information of the resource to have a second completeness, which indicates that the issuance information meets the basic requirements for initiating a registration and filing process, and that the completeness of the issuance information meets the highest standard.

[0108] Optionally, the first node can add a completeness identifier to the issuance information based on its completeness, thereby instructing the second node that verifies and reviews the issuance information to prioritize the registration and filing of issuance information with higher completeness (e.g., issuance information that meets the second completeness requirement), so as to improve the efficiency of resource registration and filing; the first node can refuse to initiate the registration and filing process for resources with incomplete issuance information (e.g., issuance information that does not meet the first completeness requirement), thereby further avoiding the problem of incomplete registration and filing information and maintaining industry standardization.

[0109] 602. The first node sends the release information of the resource with the release signature added to it to the second node.

[0110] This step is similar to step 402 and will not be repeated here.

[0111] Optionally, the first node also sends the public key of the issuance to the second node to verify whether the issuance information has been changed, so that the second node can register and file the transaction after verifying that the issuance information has not been tampered with, thereby further ensuring the security of the resource transaction.

[0112] 603. The second node adds a filing signature to the received issuance information that has already been signed. This filing signature is used to verify whether the resource has been registered.

[0113] In some embodiments, the signature algorithm used by the second node to add the registration signature can be a signature algorithm that has been agreed upon by all nodes in the system. In this example, each node in the system stores the verification algorithm corresponding to the signature algorithm, so that the registration signature can be verified based on the verification algorithm.

[0114] In some embodiments, the second node includes multiple child nodes, for example... Figure 5 In this example, the evidence storage and signing node 521 and the supervision node 522 are included in the second node. The multiple child nodes included in the second node sequentially perform filing and signing on the issuance information. For example, the evidence storage and signing node 521 adds a first filing signature to the issuance information, and the supervision node 522 adds a second filing signature to the issuance information with the first filing signature added.

[0115] 604. The second node sends the issuance information, which has been signed with the filing, to other nodes in the system.

[0116] In some embodiments, when the second node sends the issuance information with the added filing signature, it also sends a filing public key for verifying the filing signature, thereby improving the efficiency of each node in verifying whether the issuance information has been registered.

[0117] 605. Multiple nodes in the system run resource contracts for the resource on the blockchain.

[0118] Once the second node sends the issuance information with the added filing signature to other nodes in the system, the first and third nodes in the system can run the resource contract based on the filing public key, provided that the resource corresponding to the issuance information has been registered and filed.

[0119] The above steps 601 to 605 describe the process of providing issuance information storage and registration services for the blockchain-based resource system. Next, steps 606 to 609 will explain the process of providing share registration services for the blockchain-based resource system.

[0120] 606. The client corresponding to the target object initiates a resource purchase transaction for the resource to the third node to execute the resource purchase transaction.

[0121] In some embodiments, the third node is a blockchain node corresponding to the resource trading platform, and the client corresponds to the target object's account in the blockchain. The execution process of the resource subscription transaction includes: the client responding to the resource subscription transaction initiated by the target object's account, and providing funds to the resource's trading account with the target object's full authorization; the trading platform managing the trading account receiving the funds provided by the target object, confirming that the resource subscription transaction has been executed, and returning transaction processing information to the client, wherein the transaction processing information may indicate that the funds used to subscribe for the resource have been successfully transferred to the resource's trading account, pending confirmation of the shareholding in the resource.

[0122] 607. When the third node detects that the resource purchase transaction of the target object has been executed, it triggers the target object's share registration request for the resource.

[0123] In some embodiments, the third node, having obtained full authorization from the target object, acquires the target object's account information, verifies the account information, and, if the verification passes, triggers the target object's share registration request.

[0124] Optionally, the account information includes the target entity's capital verification information, which indicates the amount the target entity can assume. The third node compares the capital verification information with the target amount of the resource. If the amount indicated by the capital verification information exceeds the target amount of the resource, the verification passes, triggering the target entity's share registration request.

[0125] Optionally, the third node can refer to the target amount of resources of the same type as the resource, or the target amount of resources issued by the same resource issuing institution, to determine the target amount of the resource. It should be noted that the target amount is only used to assess whether the target object belongs to the target group of the resource, and will not be used as valid data to represent the expected value of the resource.

[0126] The above technical solution verifies the eligibility of the target entity that initiates the resource purchase request, thereby preventing entities whose qualifications do not match the resource from purchasing it, and further ensuring the security of resource transactions.

[0127] 608. In response to the share registration request, the third node determines the target object's resource share information for the resource based on the resource contract included in the issuance information. The resource share information includes the target object's share of the resource.

[0128] In some embodiments, the resource share information includes the target object's share of the resource and the value corresponding to the share. The process of determining the resource share information includes the following steps 1 and 2.

[0129] Step 1: The third node responds to the share registration request and obtains the share value of the resource from the transaction account.

[0130] The share value is the value per unit share, used to determine the value corresponding to the share to be registered as the target object. The third node is a blockchain node corresponding to the resource trading platform, which manages the resource trading accounts. In some embodiments, the share value of the resource is determined on a daily basis, with the trading platform determining the share value at a target time each day. In this example, the third node can obtain the share value of the resource from the trading account based on the current time. If the current time is before the target time, the share value is the share value of the resource determined at the target time of that day; if the current time is after the target time, the share value is the share value of the resource determined at the target time of the next day. Of course, the share value of the resource can also be determined on a period of three days, one week, or one month, and this application does not limit this.

[0131] Step 2: The share registration request carries the subscription value corresponding to the resource subscription transaction. The third node determines the target object's share of the resource and the value corresponding to the share based on the share value, the subscription value, and the resource contract.

[0132] The subscription value is the value provided by the target entity. Optionally, the value provided by the target entity is determined based on the amount of funds provided by the target entity.

[0133] In some embodiments, the resource contract provides trading rules that indicate the rate for subscribing to the resource. In response to a target object's share registration request for the resource, the third node determines the target object's net subscription value based on the value provided by the target object and the rate indicated by the resource contract. The third node then determines the target object's share of the resource based on the ratio between the net subscription value and the share value, whereby the value corresponding to the share is the net subscription value.

[0134] 609. The third node stores the resource share information of the target object on the blockchain.

[0135] In some embodiments, the resource share information includes the target object's share of the resource and the value corresponding to that share.

[0136] In other embodiments, the share registration request carries the target object's account address on the blockchain, and step 609 can be implemented through steps A and B below.

[0137] Step A: The third node generates a digital proof for trading the resource based on the target object's share of the resource. The number of digital proofs indicates the target object's share of the resource.

[0138] In some embodiments, the third node can generate a digital proof for the target object to trade the resource, based on a proof protocol agreed upon with other nodes in the system. Optionally, the proof protocol specifies the information that the digital proof should include and the standards it should follow, such as the identifier field of the digital proof, the number of digital proofs, the minimum splitting unit supported by the digital proof, and the total number of digital proofs, etc., which are not limited in this application.

[0139] Step B: The third node stores the digital proof to the target object's account address on the blockchain.

[0140] Ownership of the digital certificate represents ownership of the share of the resource. The third node determines ownership of the digital certificate by storing it in the target object's account address on the blockchain. Based on this, the target object can trade its share of the resource by trading the digital certificate.

[0141] In some embodiments, the third node can respond to a share transfer request initiated by the target object and update the target object's resource share information on the blockchain based on the resource contract. Optionally, the share transfer request indicates the share to be transferred and the transferee. In this example, the third node updates the target object's share of the resource and the value corresponding to the share, and transfers the digital proof of the target quantity corresponding to the transferred share from the target object's account address on the blockchain to the transferee's account address on the blockchain, thus completing the on-chain digital proof transfer.

[0142] The above technical solution registers the share of resources as digital proofs that can circulate on the blockchain. While ensuring the rights and interests of resource holders, it provides a secondary trading market based on blockchain, which greatly improves the liquidity of resources while ensuring the security of resource transactions.

[0143] 610. The third node returns to the client a successful purchase notification for the resource by the target object.

[0144] The registration success information indicates that the resource subscription transaction has been completed and the holding share of the resource has been confirmed. In some embodiments, the subscription success information includes the target entity's holding share of the resource, the confirmation time of the holding share, and the value corresponding to the holding share.

[0145] Steps 606 to 610 above describe the process of providing share registration services for the blockchain-based resource management system. Next, steps 611 to 613 describe the process of providing value update services and monitoring services for the blockchain-based resource management system.

[0146] 611. Every target period, the third node obtains the current share value of the resource from the transaction account and stores the current share value of the resource on the blockchain.

[0147] In some embodiments, the target period is the same as the period for determining the share value of the resource. For example, the trading platform uses days as the determination period and determines the share value of the resource at a target time each day. The third node obtains the current share value of the resource from the trading account every other day. In other embodiments, the target period is different from the period for determining the share value of the resource. The third node obtains the current share value of the resource from the trading account every two days. The description of the period for determining the share value is referenced in step 1 of step 608 and will not be repeated here.

[0148] The above process enables the updating of the value of a resource. By recording the history of changes in the share value of the resource on the blockchain, and based on the immutability of the blockchain, a reliable record can be left for the transaction process of the resource, providing data security for tracing historical transactions.

[0149] 612. The second node responds to the third node by storing the current share value of the resource on the blockchain and obtains the reference value of the resource.

[0150] Optionally, the reference value is the share value of the resource obtained from a trusted source, used to determine the accuracy of the share value stored by the third node. Optionally, this step can be performed by a child node in the second node that provides supervision services, for example, Figure 5 Supervision node 522 in the middle.

[0151] 613. If the current share value and the reference value are inconsistent, the second node shall terminate the transaction process of the resource.

[0152] The second node compares the share value stored by the third node with the reference value obtained from a trusted source, enabling it to monitor the reliability of the value updated by the third node in real time. This allows for timely intervention to stop losses in case of erroneous value updates, further enhancing transaction security. Optionally, this step can be performed by a child node within the second node that provides monitoring services, for example... Figure 5 Supervision node 522 in the middle.

[0153] Steps 611 to 613 above describe the process of providing monitoring services to the blockchain-based resource management system. Next, steps 614 and 615 describe the process of providing settlement services to the blockchain-based resource management system.

[0154] 614. In response to a settlement request for the resource, the third node determines the number of digital proofs on the blockchain used to trade the resource, and the number of digital proofs stored in an account address on the blockchain indicates the share of the resource held by that account address.

[0155] The settlement request instructs that, based on the holding shares of each object, the total value of the resource currently corresponding to that object be allocated to the objects holding those shares. In some embodiments, the settlement request may be triggered by the trading platform corresponding to the resource, or by the regulatory agency corresponding to the second node.

[0156] In some embodiments, the third node reads resource share information recorded based on multiple share registration requests and share transfer requests, and determines multiple account addresses holding shares of the resource and the number of digital proofs held by the multiple account addresses for trading the resource.

[0157] In some embodiments, the third node stops providing share registration services in response to a settlement request for the resource.

[0158] 615. The third node settles the resource based on the number of digital proofs. Once the settlement is complete, the digital proofs stored at the account address on the blockchain are marked as settled.

[0159] In some embodiments, a digital certificate can be marked as settled by transferring it to a target address. It is understood that when any subsequent transaction for that digital certificate identifies the target address in the circulation record of that digital certificate, it can be determined that the digital certificate has been settled.

[0160] In some embodiments, the process by which the third node settles the resource based on the number of digital proofs includes the following steps (1) to (3).

[0161] Step (1): The third node responds to the settlement request for the resource and obtains the final share value of the resource from the transaction account.

[0162] This step (1) refers to steps 608 and 611, and will not be repeated here. Optionally, the third node can obtain a reliable final reference share value from the second node to ensure the accuracy of the final share value obtained from the trading account.

[0163] Step (2): The third node determines the settlement value corresponding to the account address based on the final share value and the number of digital proofs stored in the account address.

[0164] The third node can determine the share of the resource held by the object corresponding to the account address based on the algorithm or standard used to determine the digital proof and the number of digital proofs. In some embodiments, the third node can determine the share of the resource held by the object corresponding to the account address based on a pre-stored conversion relationship between shareholding and digital proofs.

[0165] In some embodiments, the third node obtains the settlement value based on the final share value and the holding share corresponding to the account address. Optionally, the resource contract includes a settlement fee rate at the time of resource settlement, and the third node determines the settlement value corresponding to the account address by subtracting the product between the final share value and the holding share corresponding to the account address based on the settlement fee rate.

[0166] Step (3): Based on the settlement value, the third node instructs the transaction account to transfer resources to the object corresponding to the account address.

[0167] Optionally, the third node, based on the subscription transaction account used by the object corresponding to the account address when subscribing to the resource share, instructs the transaction account to transfer resources to the subscription transaction account according to the settlement value. Based on this, the final settlement funds of the object are returned along the same path as the funds provided when the object subscribed to the share, ensuring the consistency of the fund flow and further enhancing the security and standardization of the transaction.

[0168] Through the above technical solutions, each node involved in the resource transaction process can verify whether the resource has been registered and filed based on the registration signature, effectively ensuring the reliability of the resource. Based on the immutability and decentralization of blockchain, the credibility and transparency of issuance information and resource share information are effectively improved, thereby effectively enhancing the security of resource transactions. Furthermore, registering the holding share of the resource as a digital proof that can circulate on the chain provides a blockchain-based secondary trading market, which greatly improves the liquidity of resources while ensuring the security of resource transactions.

[0169] To facilitate understanding the above Figure 5 and Figure 6 The implementation principles of various services in the provided blockchain-based resource management system are illustrated in the following embodiment: a schematic diagram of the resource management process is provided. (See attached diagram.) Figure 7 . Figure 7 This is a schematic diagram of a resource management process provided in an embodiment of this application, such as... Figure 7 As shown in Figure (a), the resource issuing institution stores the resource issuance information on the blockchain through the issuance information storage function provided by the first node. The first node adds an issuance signature to the resource issuance information and initiates registration and filing with the second node. The regulatory agency confirms the validity of the resource issuance information and adds a filing signature to the resource issuance information through the registration and filing service provided by the second node. Figure 7 As shown in Figure (b), the subscriber initiates a resource subscription transaction to the resource trading platform. The resource trading platform triggers the share registration service provided by the third node. Based on the value update service provided by the third node, the subscriber's holding shares are registered on the blockchain, and a successful subscription message is returned to the subscriber. The regulatory agency supervises the above share registration and value update processes through the supervision service provided by the second node. Figure 7 As shown in Figure (c), the trading platform provides settlement services through a third node, locks up share registration services (preventing share transfer or subscription), settles resources based on value update services, and returns resource settlement funds to the settlement object. The settlement service includes a process of deducting handling fees to return issuance settlement funds to the resource issuing institution. The regulatory agency supervises the above settlement process through the supervision services provided by the second node.

[0170] This application provides a computer device capable of functioning as a first node, second node, or third node in the aforementioned blockchain-based resource management system, thereby implementing the blockchain-based resource management method provided in the various embodiments described above. The structure of this computer device is described below:

[0171] Figure 8This is a schematic diagram of the structure of a computer device provided in an embodiment of this application. The computer device 800 can vary significantly due to differences in configuration or performance. It may include one or more Central Processing Units (CPUs) 801 and one or more memories 802. The one or more memories 802 store at least one computer program, which is loaded and executed by the one or more processors 801 to implement the methods provided in the various method embodiments described above. Of course, the computer device 800 may also have wired or wireless network interfaces, a keyboard, and input / output interfaces for input and output. The computer device 800 may also include other components for implementing device functions, which will not be elaborated upon here.

[0172] In an exemplary embodiment, a computer-readable storage medium is also provided, such as a memory including a computer program that can be executed by a processor to perform the blockchain-based resource management method in the above embodiments. For example, the computer-readable storage medium may be a read-only memory (ROM), a random access memory (RAM), a compact disc read-only memory (CD-ROM), magnetic tape, floppy disk, and optical data storage device, etc.

[0173] In an exemplary embodiment, a computer program product or computer program is also provided, which includes program code stored in a computer-readable storage medium. The processor of a computer device reads the program code from the computer-readable storage medium and executes the program code, causing the computer device to perform the above-described blockchain-based resource management method.

[0174] Those skilled in the art will understand that all or part of the steps of the above embodiments can be implemented by hardware or by a program instructing related hardware. The program can be stored in a computer-readable storage medium, such as a read-only memory, a disk, or an optical disk.

[0175] The above are merely optional embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A blockchain-based resource management system, characterized in that, The system includes a first node, a second node, and a third node; The first node is configured to respond to a resource issuance request by storing the resource issuance information on the blockchain and sending the resource issuance information to the second node. The issuance information includes the transaction account and resource contract corresponding to the resource, and the resource contract is used to execute the transaction process of the resource. The second node is used to add a filing signature to the received issuance information, send the issuance information with the added filing signature to other nodes in the system, and run the resource contract on the blockchain. The filing signature is used to verify whether the resource has been registered. The third node is used to respond to the target object's share registration request for the resource, and store the target object's resource share information on the blockchain based on the resource contract included in the issuance information. The resource share information includes the target object's share of the resource. The share registration request is triggered when it is detected that the funds corresponding to the target object's resource subscription transaction have been transferred to the trading account. The resource subscription transaction is a transaction in which the target object transfers funds to the trading account to subscribe for the resource.

2. The system according to claim 1, characterized in that, The first node is used for: In response to a request to issue the resource, an issuance signature is added to the issuance information of the resource, the issuance information with the added issuance signature is stored on the blockchain, and the issuance information with the added issuance signature is sent to the second node. The issuance signature is used to verify whether the issuance information has been changed.

3. The system according to claim 1, characterized in that, The share registration request carries the account address of the target object on the blockchain, and the third node is used for: Based on the share registration request and the resource contract, the target object's share of the resource is determined; Based on the target object's share of the resource, a digital proof for trading the resource is generated, the number of the digital proofs indicating the target object's share of the resource; The digital proof is stored in the target object's account address on the blockchain.

4. The system according to claim 3, characterized in that, The third node is also used for: In response to a share transfer request initiated by the target object, the resource share information of the target object is updated on the blockchain based on the resource contract.

5. The system according to claim 4, characterized in that, The share transfer request indicates the share to be transferred and the transferee; the third node is also used for: The digital proof of the target quantity corresponding to the transferred share is transferred from the target object's account address on the blockchain to the transfer object's account address on the blockchain.

6. The system according to claim 1, characterized in that, The share registration request carries the subscription value corresponding to the resource subscription transaction, and the third node is used for: In response to the share registration request, the share value of the resource is obtained from the trading account; Based on the share value, the subscription value, and the resource contract, the resource share information of the target object is stored on the blockchain. The resource share information includes the target object's share of the resource and the value corresponding to the share.

7. The system according to claim 1, characterized in that, The third node is also used for: Every target period, the current share value of the resource is obtained from the transaction account and stored on the blockchain.

8. The system according to claim 7, characterized in that, The second node is also used for: In response to the third node storing the current share value of the resource on the blockchain, the reference value of the resource is obtained; If the current share value and the reference value are inconsistent, the transaction process for the resource shall be terminated.

9. The system according to claim 1, characterized in that, The third node is also used for: In response to a settlement request for the resource, the number of digital proofs on the blockchain used to trade the resource is determined, wherein the number of digital proofs stored in an account address on the blockchain indicates the share of the resource held by the account address; The resources are settled based on the number of digital proofs. Once the settlement is complete, the digital proofs stored at the account addresses on the blockchain are marked as settled.

10. The system according to claim 9, characterized in that, The third node is used for: In response to a settlement request for the resource, the final share value of the resource is obtained from the transaction account; The settlement value corresponding to the account address is determined based on the final share value and the number of digital proofs stored in the account address. Based on the settlement value, the transaction account is instructed to transfer resources to the object corresponding to the account address.

11. A blockchain-based resource management method, characterized in that, The method is applied in a blockchain-based resource management system, the system comprising a first node, a second node, and a third node; the method includes: In response to a resource issuance request, the first node stores the resource issuance information on the blockchain and sends the resource issuance information to the second node. The issuance information includes the transaction account and resource contract corresponding to the resource, and the resource contract is used to execute the transaction process of the resource. The second node adds a filing signature to the received issuance information, sends the issuance information with the filing signature to other nodes in the system, and runs the resource contract on the blockchain. The filing signature is used to verify whether the resource has been registered. In response to the target object's share registration request for the resource, the third node stores the target object's resource share information on the blockchain based on the resource contract included in the issuance information. The resource share information includes the target object's share of the resource. The share registration request is triggered when it is detected that the funds corresponding to the target object's resource subscription transaction have been transferred to the trading account. The resource subscription transaction is a transaction in which the target object transfers funds to the trading account to subscribe for the resource.

12. The method according to claim 11, characterized in that, The step of responding to a resource issuance request by storing the resource issuance information on the blockchain and sending the resource issuance information to the second node includes: In response to a request to issue the resource, an issuance signature is added to the issuance information of the resource, the issuance information with the added issuance signature is stored on the blockchain, and the issuance information with the added issuance signature is sent to the second node. The issuance signature is used to verify whether the issuance information has been changed.

13. The method according to claim 11, characterized in that, The share registration request carries the target object's account address on the blockchain; In response to the target object's request for share registration of the resource, the storage of the target object's resource share information on the blockchain based on the resource contract included in the issuance information includes: Based on the share registration request and the resource contract, the target object's share of the resource is determined; Based on the target object's share of the resource, a digital proof for trading the resource is generated, the number of the digital proofs indicating the target object's share of the resource; The digital proof is stored in the target object's account address on the blockchain.

14. The method according to claim 13, characterized in that, The method further includes: In response to a share transfer request initiated by the target object, the resource share information of the target object is updated on the blockchain based on the resource contract.

15. The method according to claim 14, characterized in that, The share transfer request indicates the share to be transferred and the transferee; the method further includes: The digital proof of the target quantity corresponding to the transferred share is transferred from the target object's account address on the blockchain to the transfer object's account address on the blockchain.

16. The method according to claim 11, characterized in that, The share registration request carries the subscription value corresponding to the resource subscription transaction; In response to the target object's request for share registration of the resource, the storage of the target object's resource share information on the blockchain based on the resource contract included in the issuance information includes: In response to the share registration request, the share value of the resource is obtained from the trading account; Based on the share value, the subscription value, and the resource contract, the resource share information of the target object is stored on the blockchain. The resource share information includes the target object's share of the resource and the value corresponding to the share.

17. The method according to claim 11, characterized in that, The method further includes: Every target period, the current share value of the resource is obtained from the transaction account and stored on the blockchain.

18. The method according to claim 17, characterized in that, The method further includes: In response to the third node storing the current share value of the resource on the blockchain, the reference value of the resource is obtained; If the current share value and the reference value are inconsistent, the transaction process for the resource shall be terminated.

19. The method according to claim 11, characterized in that, The method further includes: In response to a settlement request for the resource, the number of digital proofs on the blockchain used to trade the resource is determined, wherein the number of digital proofs stored in an account address on the blockchain indicates the share of the resource held by the account address; The resources are settled based on the number of digital proofs. Once the settlement is complete, the digital proofs stored at the account addresses on the blockchain are marked as settled.

20. The method according to claim 19, characterized in that, The method further includes: In response to a settlement request for the resource, the final share value of the resource is obtained from the transaction account; The settlement value corresponding to the account address is determined based on the final share value and the number of digital proofs stored in the account address. Based on the settlement value, the transaction account is instructed to transfer resources to the object corresponding to the account address.

21. A computer device, characterized in that, The computer device includes one or more processors and one or more memories, wherein at least one computer program is stored in the one or more memories, and the computer program is loaded and executed by the one or more processors to implement the blockchain-based resource management method as described in any one of claims 11-20.

22. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores at least one computer program, which is loaded and executed by a processor to implement the blockchain-based resource management method as described in any one of claims 11-20.

23. A computer program product, characterized in that, The computer program product includes program code stored in a computer-readable storage medium. A processor of a computer device reads the program code from the computer-readable storage medium and executes the program code, causing the computer device to perform the blockchain-based resource management method as described in any one of claims 11-20.

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