A blockchain-based asset data management method and system

Abstract

The present application discloses a blockchain-based asset data management method, characterized in that it includes a network topology jointly constructed by an authentication center, a management platform, and a consortium blockchain, and combines a hyperledger to store data. In this method, the asset data is sent to the management platform after being generated. The platform generates a hash fingerprint after storing the data and feeds it back to the chain. When a property rights dispute occurs, the authentication center can be triggered to download the original data from the management platform and call the hash fingerprint on the chain to generate an identification report and a verification QR code; the authentication center verifies the user information and then generates a Token broadcast on the chain; the data is divided into metadata and fingerprint hash, the metadata is uploaded to the IPFS cluster, and the fingerprint hash is uploaded to the chain; finally, a decentralized anonymous identity authentication method is proposed. The present application also discloses an asset data management system based on blockchain, which includes a business layer, a contract layer, a network layer, a consensus layer, and a data layer, and has the above-mentioned beneficial effects.

Description

Technical Field

[0001] The present application belongs to the field of computer application technology, and in particular, relates to a blockchain-based asset data management method and system. Background Art

[0002] We live in a highly information-based era. With the development of society and the advancement of science and technology, enterprises or institutions need to store digital information or content related to them and of certain value in their production and life. This type of information can be defined as digital assets. As an intangible asset, digital assets run through the entire operation process of an enterprise, but they are usually not fully managed and utilized. In fact, by using scientific digital asset management methods, the potential value of digital assets can be maximized. In recent years, people have conducted research on digital asset management and trading. The digitization of asset information has the attributes of digital assets and is valuable and sensitive data. Centralized systems can ensure its security and reliability, but asset data as digital assets still have the following disadvantages in terms of storage and transfer: (1) Due to its centralized storage, traditional digital asset management platforms inevitably have problems such as closed systems, difficulty in expansion, data reliability, and storage efficiency; (2) As a commodity in the transaction process, if the ownership of the rights cannot be determined, the digital asset transfer cannot be carried out normally; (3) The existing digital copyright protection method is centralized registration, which has problems such as difficulty in rights confirmation, serious piracy, poor publicity, and high copyright protection costs; (4) For digital asset data that needs to be encrypted and stored, centralized platforms are prone to privacy leaks, and there are security risks such as data tampering, information disputes, and hacker attacks.

[0003] As a new Internet technology that is transparent, open, trustworthy, and decentralized, blockchain technology has gradually been used in the construction of digital asset management platforms. Existing digital asset management platform projects based on public chains are constrained by factors such as the increase in block size, long data confirmation time, and low block transaction frequency, and cannot serve digital asset management and its related applications well. In contrast to public chains, permissioned blockchains require explicit approval from the network to access the chain and ledger. This property can be regarded as a private network that acts as a closed ecosystem, allowing only authorized nodes to view or verify transactions approved by the central authority, and the most mainstream permissioned blockchain platform is Hyperledger Fabric. Therefore, it is necessary to combine consortium blockchain technology to design a digital asset trusted evidence management mechanism based on permissioned blockchains, relying on the weak centralization of permissioned blockchains to solve the problems of storage efficiency and consensus efficiency in digital asset management and the trustworthiness of digital copyright authentication in public chain systems. Summary of the invention

[0004] In order to solve the above-mentioned problems of existing digital asset data management, the present application provides a blockchain-based asset data management method and system, which manages asset data as digital assets, realizes decentralization, trusted storage, non-tamperability, traceability and other technical characteristics in blockchain technology, and combines the blockchain distributed data management tool IPFS to build a new asset data management system that takes into account high performance, economy and flexibility.

[0005] In a first aspect, the present application provides an asset data management method based on blockchain.

[0006] This method defines a network topology that is jointly constructed by roles such as the authentication center, management platform, alliance blockchain, and system users, and combines the alliance chain Fabric and IPFS file system for data storage and authentication.

[0007] Furthermore, the asset data management method defines a blockchain-based asset data management system architecture that should be divided into business layer, contract layer, network layer, consensus layer and data layer from top to bottom. The business layer includes user registration and login, asset data storage and verification, account information management and privacy protection, etc. The contract layer includes identity authentication, asset entry, asset exit, audit tracking, etc. The network layer encapsulates the P2P networking mechanism, Gossip transmission protocol and data verification mechanism. The consensus layer includes Kafka cluster and associated Zookeeper cluster based on several Orderer nodes. The data layer is the core of the system, which is composed of the IPFS database and alliance chain Fabric in the management platform.

[0008] Furthermore, the method is defined in terms of system user registration, and adopts a method of generating tokens. The authentication center verifies the user's identity information and broadcasts the token generated based on the identity to the blockchain network. If more than half of the nodes return a successful reception result, the smart contract is triggered and the token is stored on the chain.

[0009] Furthermore, in terms of asset data uploading, it can be divided into two parts according to the content of asset data transmission: metadata transmission and fingerprint hash transmission. The asset metadata is uploaded to the IPFS cluster by the management platform, and the fingerprint hash is uploaded to the blockchain network. The fingerprint hash is used to cooperate with the metadata for asset authentication.

[0010] Among them, when there is no need to provide a validation certificate to meet the authenticity and traceability of the on-chain data, you can skip the blockchain and use IPFS directly for query.

[0011] Finally, considering that the solution for system user identity management relies on a centralized trusted party management platform, which causes the user's personal identity information to be controlled by the management platform, a decentralized anonymous identity authentication method is proposed in combination with the system architecture described in the above method. The method is divided into initialization stage, registration stage and authentication stage.

[0012] 1) In the initialization phase, the authentication center generates its own public-private key pair, then publishes the public key to the system and the blockchain network. System users independently generate their identity information and corresponding public-private keys.

[0013] 2) During the registration phase, users should send their identity information and public key to the authentication center for registration in order to obtain valid identity proof; at the same time, users can obtain multiple verifiable proofs from the authentication center based on their multiple different identity information.

[0014] 3) In the authentication phase, the user sends a publicly verifiable identity certificate and corresponding public information generated by the authentication center to the blockchain in the form of a transaction, and the transaction is eventually added to the blockchain. After the identity information is uploaded to the blockchain, other users in the system can query the user's public information through the blockchain to verify the user's identity.

[0015] On the second aspect, the present application provides an asset data management system based on blockchain.

[0016] The system is composed of the IPFS and Fabric, wherein the management platform integrates the IPFS cluster and the authentication center is defined as a node in the Fabric network; the system has all the beneficial features and effects of the aforementioned blockchain-based asset data management method.

[0017] Based on the various roles in the system, the asset data storage and chain-up process in the system is proposed, which is briefly described as follows:

[0018] 1) Ordinary depository users send digital asset information to the management platform;

[0019] 2) The platform stores the data and generates a fingerprint hash of the data;

[0020] 3) The fingerprint hash is then fed back to the alliance chain Fabric node and stored on the chain;

[0021] 4) Each node in the Fabric network synchronizes transaction information in real time and generates endorsements and packages them on the chain;

[0022] 5) When a system user has a digital asset copyright dispute or asset content dispute with others, the authentication center will be triggered to send a request to the management platform to download the original data file;

[0023] 6) The authentication center calls the smart contract to request the fingerprint hash from the Fabric network;

[0024] 7) Verify the fingerprint hash calculated from the request file by comparing it with the fingerprint hash on the chain;

[0025] 8) The certification center generates an identification report and the corresponding QR code, and provides verification results to system users in a timely manner;

[0026] 9) System users can access the mobile terminal to obtain identification results and query data information in real time by scanning the QR code.

[0027] It should be emphasized that when a user logs in to the system, the adjacent Peer node assigned by the system in the blockchain network authenticates the user ID that submits the information, simulates the execution of the endorsement signature, and returns the execution result to the original Peer node. If the authentication is passed, the user can log in to the system.

[0028] Furthermore, when the user uploads data to the system, the user transmits a shared symmetric key to the node based on the public key of the adjacent Peer node, and uses the key to encrypt the metadata and send it to the node. After receiving the data, the node can decrypt it to obtain the metadata in preparation for subsequent authorized access.

[0029] Furthermore, the IPFS cluster in the system needs to select several relatively active nodes based on performance, and only the selected nodes can receive metadata shards and generate hash fingerprints.

[0030] Compared with the existing technology, the advantages of this application are: it solves the defects of centralized storage of asset data, while ensuring the decentralization, trusted storage and traceability of digital asset storage applications blockchain, it can also take into account the performance, practicality and flexibility of data storage, and realize the internal autonomy, identity security and privacy security of users of the digital asset management system. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. It should be understood that the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0032] Figure 1 It is the process of storing and uploading asset data on the blockchain in the blockchain-based asset data management system.

[0033] Figure 2 This is a diagram of the technical architecture of a blockchain-based asset data management system.

[0034] Figure 3 It is a detailed design flow chart of the asset data management system.

[0035] Figure 4 It is a flow chart of an anonymous identity authentication method. DETAILED DESCRIPTION

[0036] In order to more clearly illustrate the technical solutions, purposes and advantages of the present application, the present application is combined with the following embodiments and embodiment drawings to provide a more profound and complete description of the application content. It should be understood that the specific embodiments described herein are used to explain the present application and cannot limit the present application. The described embodiments refer only to a part of the embodiments of the present application, rather than all embodiments. The techniques, methods and equipment known to ordinary technicians in the relevant fields may not be discussed in detail, but in appropriate cases, the techniques, methods and equipment should be regarded as part of the specification. Based on the embodiments of the present application, other embodiments obtained by technicians in the relevant fields before doing creative work all belong to the scope of protection of the present application.

[0037] The core of this application is to propose a blockchain-based asset data management method and system, which solves the drawbacks of the existing digital asset data management process by combining the current mainstream permissioned blockchain technology Hyperledger Fabric and the distributed database management tool IPFS. While taking into account the high performance, economy and flexibility of data storage in the existing system, it can also meet the decentralization, trusted storage and traceability after the application of blockchain technology.

[0038] Hyperledger Fabric is the first open source project of the consortium chain. Its design purpose is to develop a blockchain underlying platform that focuses on future auditability and data protection. The project is based on a modular design, which also provides developers with scalability and flexibility for different business scenarios. Fabric identity management is based on the PKI system, node identity management is based on X.509 certificates, ledger management is based on CounchDB and Blockfile text, and transaction management is based on the Gossip protocol. The bottom layer of Fabric is composed of various distributed clusters, including several Peer nodes that store ledger definitions and call smart contracts under the organization (a Leader node will be defined in several Peer nodes under each organization), Orderer nodes participating in the sorting consensus, and Clients.

[0039] IPFS Galaxy File System is a new network protocol designed to create persistent and distributed storage and shared files. Its features such as addressable storage content and traceable file modification history provide conditions for blockchain data information to be off-chain, and can effectively alleviate the excessive load of traditional information systems.

[0040] It is specially noted here that the Fabric technology and IPFS technology mentioned in this application are only pointed out as a part of the system architecture and business system designed by this application, and are not involved in the scope of protection of the technical content of this application.

[0041] The following combination Figure 1 , describing the process of storing and uploading asset data on the chain in the method provided in this application.

[0042] It specifically includes the following steps:

[0043] S101: In the asset data management system, the general depository user sends the digital asset information to the management platform;

[0044] S102: The platform stores the data and generates a fingerprint hash of the data;

[0045] S103: The fingerprint hash is then fed back to the alliance chain Fabric node and stored on the chain;

[0046] S104: Each node in the Fabric network synchronizes transaction information in real time and generates endorsements and packages them on the chain;

[0047] S105: When a system user has a digital asset copyright dispute or asset content dispute with others, the authentication center is triggered to send a request to the management platform to download the original data file;

[0048] S106: The authentication center calls the smart contract to request the fingerprint hash from the Fabric network; the fingerprint hash calculated by the request file is compared with the fingerprint hash on the chain for verification;

[0049] The S107 Certification Center generates an identification report and a corresponding QR code, and provides verification results to system users in a timely manner; system users can access the mobile terminal to obtain identification results and query data information in real time by scanning the QR code.

[0050] It should be emphasized that the authentication center needs to store and obtain the data information on the blockchain in real time to ensure the timeliness and credibility of the data. The authentication center should be a Peer node in the Fabric network. The underlying blockchain is an authorized alliance chain, including the authentication center, identity management center (CA), auditor, consensus components, etc., which are all components of the blockchain network.

[0051] In terms of the number of nodes, in addition to the system itself, the certification center and the audit (at least one) serving as the leader nodes of their respective organizations, new leader nodes can be appropriately allocated according to business expansion and the increase of data sharing parties, or new peer nodes can be added under their organizations, which will not affect the performance while meeting the scalability of the system. In addition to completing transaction sorting and consensus, the Orderer node also needs to consider fault tolerance in the alliance chain network, so the number is set as follows: the number of Orderer nodes is greater than or equal to one-third of the number of alliance chain organizations.

[0052] Furthermore, a technical architecture diagram of an asset data management system based on blockchain is provided for the embodiment of the present application, such as Figure 2 As shown in the figure, the architecture can be divided into business layer, contract layer, network layer, consensus layer and data layer from top to bottom. It specifically includes:

[0053] S201: The business layer provides users with various blockchain-based applications by calling the contract layer interface through the mobile client, including user registration and login, asset data storage and verification, account information management and privacy protection, etc.

[0054] S202: The contract layer is used to write the trusted distributed system business execution logic in the blockchain, implement specific operations on the data layer data, and thus complete the indirect connection between the data layer and the core business of its upper layer. The specific operations include identity authentication, asset entry and exit, audit tracking, etc. Once such operation interfaces are called by the business layer, they will be automatically executed;

[0055] S203: The network layer encapsulates the P2P networking mechanism, Gossip transmission protocol and data verification mechanism to achieve fast synchronization and verification between data of each node in the distributed network;

[0056] S204: The consensus layer uses the Kafka sorting consensus component, which is based on the Orderer node in the Fabric network. It includes the Kafka cluster and the associated Zookeeper cluster based on several Orderer nodes and is operated and managed in the form of a mirror.

[0057] S205: The data layer is the core part of the system. This layer is composed of the management platform IPFS database and the alliance chain Fabric. It encapsulates all the information of trusted asset data storage, including account information, metadata, metadata fingerprint hash and system configuration information.

[0058] Furthermore, combined with the above-described system asset data storage and chain process and the system's technical architecture, a detailed design flow chart of the asset data management system is proposed. Figure 3 As shown, the specific operation process is as follows:

[0059] S301: The neighboring Peer node assigned by the system in the blockchain network authenticates the user ID that submitted the information, and simulates the execution of endorsement signature (the transaction information in this step is not written into the account book), and the execution result is returned to the original Peer node. If the authentication is passed, the user can log in to the system;

[0060] S302: The user transmits a shared symmetric key to the neighboring peer node based on the public key of the peer node, and uses the key to encrypt metadata and then sends it to the node. After receiving the data, the node can decrypt the metadata to prepare for subsequent authorized access;

[0061] S303: Select several relatively active nodes in the IPFS cluster based on performance;

[0062] S304: Send the metadata file shard to the selected node in the IPFS cluster and generate a data fingerprint hash;

[0063] S305: The system automatically executes the smart contract to upload the fingerprint hash corresponding to the metadata information to the alliance chain Fabric;

[0064] S306: When the authenticity of the on-chain data needs to be verified or an asset dispute occurs, the interface is called to access the IPFS cluster to download the metadata file shards and restore them;

[0065] S307: Write the authorization information of the call authentication into the blockchain to supervise the call authorization status;

[0066] S308: Leader Peer (the main node in Fabric) packages the transaction into the chain, waits for the endorsing node to simulate the endorsement signature of the transaction, then performs secondary endorsement after consensus sorting by the Orderer cluster (the sorting component in Fabric), and finally packages the transaction into blocks and sends them to each accounting node;

[0067] S309: The accounting node synchronizes and backs up the transaction information in the broadcast transaction in real time after endorsement sorting and block formation;

[0068] S310: The authentication center authorizes the IPFS cluster to access metadata and calculates the fingerprint hash of the metadata;

[0069] S311: The authentication center calls the smart contract to obtain the fingerprint hash on the blockchain and compares it with the above fingerprint hash. If the two are consistent, it proves that the file data is accurate and has not been tampered with;

[0070] S312: The authentication center generates an authentication report online and generates a queryable QR code based on the data fingerprint hash. The QR code uniquely corresponds to the fingerprint hash and authentication report of the data.

[0071] S313: System users scan the QR code to obtain the appraisal report results, initiate online adjudication of asset data and insurance claims, and resolve business disputes.

[0072] Specifically, the operation process in the system user registration part is as follows:

[0073] When a user initiates an account registration request to the system, the request includes the user's real identity, asset share, etc. After the administrator reviews and confirms the user information, the nearby Peer node in the system will automatically generate a user public key and a user private key for the registered user, and use the user public key, the signature of the Peer node in the system on the user public key, and the timestamp to form a Token, and send a registration request for the Token to the Leader Peer.

[0074] The Leader Peer performs a secondary authentication on the user's identity to ensure that the public key assigned by the user is not on the revocation list and confirms that the Peer signature and timestamp in the Token are authentic and valid.

[0075] As a node, the authentication center will also verify the user's identity information. The Token will be broadcast to the entire network. If more than half of the nodes receive and return a successful result, the smart contract will be triggered and the Token will be stored on the chain.

[0076] Specifically, in terms of asset data upload, asset data transmission can be divided into two parts: metadata transmission and fingerprint hash transmission. The asset data is uploaded to the IPFS cluster by the management platform, and the transmission data format sent to the i-th Node (i=1,...,n) in the cluster is specifically described as follows: the metadata sent to the i-th Node, the identity information of the i-th Node, the signature of the Peer node that sent the metadata to the i-th Node, and the current timestamp are used as input values, and the input value is encrypted using the public key of the i-th Node, and finally the output value is generated.

[0077] The system node sends an upload request to the blockchain Fabric network, calling the smart contract to upload parameters such as fingerprint hash to the blockchain. After receiving the request, each node in the blockchain network verifies the user identity Token, then simulates the execution of endorsement, sends it to the Orderer node for sorting and packaging, and finally sends it to all accounting nodes for chain storage.

[0078] Specifically, in terms of data storage, the information stored in IPFS is hashed and stored in a Merkle Directed Acyclic Graph (MerkleDAG) to ensure the security of the information. This hash is called the address hash, also referred to as the fingerprint hash mentioned above. By storing the fingerprint hash on the chain, the metadata is replaced. In the hash calculation, the SHA256 algorithm is used twice, followed by Base58 encoding. The final generated fingerprint hash length is 33Byte. Using fingerprint hash instead of metadata on the chain will greatly reduce the size of the storage block, while achieving lightweight blockchain without losing efficiency.

[0079] Specifically, in terms of data query validation, the above data query involves two data reads and needs to be verified by the certification center, which reduces the data query efficiency to a certain extent while issuing a validation certificate. The query interface of IPFS itself can directly query asset information. Therefore, when there is no need to issue a validation certificate to meet the authenticity and traceability of the on-chain data, the blockchain can be skipped and IPFS can be used directly for querying. The query process can therefore be oriented to non-alliance nodes.

[0080] Considering that the solution for system user identity management relies on a centralized trusted party management platform, the user's personal identity information is controlled by the management platform rather than the user himself. If there are problems such as system software vulnerabilities or plagiarism by platform managers, user information may be leaked. Therefore, combined with the system architecture described above, this embodiment proposes a decentralized anonymous identity authentication method under the system.

[0081] like Figure 4 As shown, in this method, the system user independently generates his identity information (ID) and the corresponding user public key and user private key. Before implementing the identity authentication process, the user should send the identity information ID and the user public key to the authentication center for registration to obtain a valid identity certificate. In this embodiment, the user can generate multiple different user IDs, public keys based on this ID, and private key combinations based on this ID to the authentication center based on different user identity IDs to obtain multiple verifiable certificates. In order to implement the authentication process, the user sends the publicly verifiable identity certificate and corresponding public information generated by the authentication center to the blockchain in the form of a transaction. The transaction is finally added to the blockchain. After the identity information is on the chain, other users in the system can query the user's public information through the blockchain to verify the user's identity. After the authentication is completed, the user can negotiate the session key through the Diffie-Hellman key exchange protocol to ensure the privacy of subsequent session information.

[0082] For the purpose of detailed description, this application divides the scheme into three stages, namely, initialization stage, registration stage and authentication stage, which are described in detail below.

[0083] 1) Initialization phase.

[0084] Define the SHA256 function as a general hash function H , define the elliptic curve digital signature algorithm ECDSA as the signature algorithm Sig , define the RSA algorithm as an asymmetric encryption algorithm Enc .

[0085] The identity of the certification authority is recorded as Authority_ID , the center generates a public-private key pair (PK_Auth,SK_Auth) , and then the public key of the certification center PK_Auth Public to the system and published to the blockchain network.

[0086] Registered User User_i The identifier is recorded as User_ID_i , followed by the user User_i Generate your own pseudo-identity PU_i and by choosing a secret private key SK_PU_i To calculate the public key PK_PU_i , then the user based on the pseudo identity PU_i Will PK_PU_i Public to the system and published to the blockchain network.

[0087] To provide the registration function, users need to execute a smart contract (SC) , where the public and private key pair of the contract is (PK_SC, SK_SC) , from which we can know that the public parameters in the initialization phase are (H,Sig,Enc,PK_Auth,PK_PU_i,PK_SC) .

[0088] 2) Registration stage.

[0089] user User_i Through a secure transmission channel (PU_i,PK_PU_i) Send to Authority_ID .

[0090] Authority_ID Received by user User_i The information sent must first be verified (PU_i,PK_PU_i) .like PU_ i has been registered or is invalid, the request will be rejected; otherwise, Authority_ID will be PU_i Generate a valid proof Proof_PU_i , and use the private key to generate a signature on the certificate Sig_A_PU_i = Sig ( SK_Auth , ( H ( PU_i ), PK_ PU_i, Proof_PU_i , ValidTime ), ready to use SK_Auth right (H(PU_i),PK_PU_i,Proof_PU_i, ValidTime) Perform a signing operation, where ValidTime It is a proof of validity time. Authority_ID Through a secure channel (H(PU_i),PK_PU_i,Proof_PU_i,ValidTime) Send to User_i .

[0091] When the user User_i Received from Authority_ID Signature Sig_A_PU_i After that, the user sends public information to the blockchain. This public information includes (PU_i,PK_PU_i,TimeStamp,CT,Sig_A_PU_i,Sig_PU_i) ,in TimeStamp is the timestamp, where CT = Enc( PK_SC,(Proof_PU_i,ValidTime)) , ready to use PK_SC right (Proof_PU_i,ValidTime) Perform encryption operations, where Sig_PU_i = Sig(SK_PU_i,(H(TimeStamp) , CT,Sig_A_PU_i,Sig_PU_i )) , ready to use SK_PU_i right (H(TimeStamp),CT,Sig_A_PU_i,Sig_PU_i ) Perform the signing operation.

[0092] After receiving the message from PU_i, the Leader Peer in the blockchain verifies the timestamp TimeStamp Verify whether it is within the allowable range compared to the current time ValidTime Is it within the valid time? Decryption CT To obtain Proof_PU_i And verify the signature Sig_A_PU_i Is it valid? If all the above steps are passed, the Leader node will record the transaction on the chain.

[0093] 3) Certification stage.

[0094] user User_i Through a pseudo-identity PU_i First generate a random value τ and timestamp TimeStamp And calculate the signature Sig_A_PU_i = Sig(SK_PU_i,H(PU_i,τ,TimeStamp)) Next, the user User_i Information (PU_i,τ, TimeStamp,Sig_A_PU_i) Send to user User_j .

[0095] User_j Received from User_i After receiving the information, first verify the timestamp and signature. If they are correct, User_j Will be obtained from the chain PU_i The public key PK_PU_i And verify the PK_PU_i Signature Sig_A_PU_i ,like PK_PU_iOn-chain and the signature is valid, then User_i The authenticated identity is valid.

[0096] The various embodiments of the present application have been described above. The above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. A person of ordinary skill in the art may make several improvements and modifications to the present application without departing from the principles of the present application, and the scope of protection of the present application shall be subject to the claims. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or technical improvements in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A blockchain-based asset data management method, characterized in that: include: The network structure jointly constructed by the certification center, management platform, alliance blockchain and system users applies the blockchain technology hyperledger to the existing asset data management method, and combines it with the distributed data management tool IPFS to build an asset data management system; The asset data management method sends digital asset information to the management platform. The management platform generates a hash fingerprint after storing the data and feeds it back to the chain. The alliance chain hyperledger network synchronizes the transaction information in real time and generates endorsements and packages it on the chain. When a property rights dispute occurs, it will trigger the authentication center to download the original data from the management platform and call the smart contract to obtain the fingerprint hash from the chain. The authentication center requests the fingerprint hash from the hyperledger and verifies it with the hash value of the file, and finally generates an identification report and a verification QR code. The asset data management method defines an asset data management system including a business layer, a contract layer, a network layer, a consensus layer and a data layer; The business layer provides users with various blockchain-based applications by calling the contract layer interface through the mobile client, including user registration and login, asset data storage and verification, account information management and privacy protection functions; The contract layer is used to write the trusted distributed system business execution logic in the blockchain, implement specific operations on the data layer data, and thus complete the indirect connection between the data layer and the core business of the upper layer. The specific operations include identity authentication, asset entry and exit, and audit tracking. The network layer encapsulates the P2P networking mechanism, Gossip transmission protocol and data verification mechanism; The consensus layer is used to set up the system consensus mechanism, including the Kafka cluster and the associated Zookeeper cluster based on several Orderer nodes; The data layer, which is composed of the IPFS database and the consortium chain hyperledger in the management platform, encapsulates all the information of the trusted asset data storage, including account information, metadata, metadata fingerprint hash and system configuration information; The authentication center needs to store and obtain the data information on the blockchain in real time to ensure the timeliness and credibility of the data. Therefore, the authentication center acts as a Peer node in the Hyperledger network. In terms of the number of nodes, in addition to the system itself, the authentication center and the audit as the leader nodes of their respective organizations, new leader nodes are allocated according to business expansion and the increase of data sharing parties. Considering fault tolerance, the number of Orderer nodes is set to be greater than one-third of the number of alliance chain organizations. The asset entry chain includes metadata transmission and fingerprint hash transmission. The metadata is uploaded to the IPFS cluster. The metadata is encoded using the Sha256 algorithm twice and then Base58 is performed. The final generated fingerprint hash is 33Byte long and the fingerprint hash is uploaded to the blockchain by the smart contract. After receiving the request, each node in the blockchain network verifies the user identity Token, then simulates the execution of endorsement, sends it to the Orderer node for sorting and packaging, and finally sends it to all accounting nodes for chain storage.

2. The method according to claim 1, characterized in that The user registration adopts the form of the system generating a token for the user and storing it on the chain. The registration process includes: the administrator reviews the user information. After the review is passed, the system's nearby nodes will generate a public-private key pair for the registered user. The system will generate a token with the registered user's public key, node signature and timestamp and store it on the chain; the chain maintains the registration list and revocation list of all users in the form of tokens.

3. The method according to claim 1, characterized in that Asset data validation refers to data verification that involves reading data twice on the blockchain and IPFS, and requires authentication and verification; when there is no need to issue a validation certificate to meet the authenticity and traceability of the on-chain data, the blockchain validation will be skipped and IPFS will be used directly for querying, so the query process will be directed to non-alliance nodes.

4. The method according to claim 2, characterized in that: The identity authentication is intended to provide a decentralized anonymous identity authentication method to achieve the purpose of protecting the privacy of system users. The method is divided into the following stages: a) In the initialization phase, the authentication center generates its own public-private key pair, then publishes the public key to the system and the blockchain network. System users independently generate their identity information and corresponding public-private key pairs; b) During the registration phase, users should send their identity information and public key to the authentication center for registration in order to obtain valid identity proof; at the same time, users can obtain multiple verification certificates from the authentication center based on their multiple different identity information; c) During the authentication phase, the user sends a publicly verifiable identity certificate and corresponding public information generated by the authentication center to the blockchain in the form of a transaction. The transaction is eventually added to the blockchain. After the identity information is uploaded to the chain, other users in the system will query the user's public information through the blockchain to verify the user's identity.

5. An asset data management system based on blockchain, characterized in that: Using the method as claimed in claim 1 comprises: The system satisfies all the beneficial effects of the above-mentioned blockchain-based asset data management method. The system is composed of the authentication center, management platform, alliance blockchain and system users described in claim 1, and integrates all the functions of the hyperledger and IPFS in claim 1, wherein the management platform integrates the IPFS cluster, and the authentication center is only defined as a node in the hyperledger network.

6. The system according to claim 5, characterized in that In terms of user login, the system: the adjacent Peer node assigned by the system in the blockchain network authenticates the user ID that submits the information, simulates the execution of the endorsement signature, and returns the execution result to the original Peer node. If the authentication is passed, the user can log in to the system.

7. The system according to claim 5, characterized in that In terms of user data uploading, the system: the user transmits a shared symmetric key to the adjacent Peer node based on the public key of the Peer node, encrypts the metadata with the symmetric key and sends it to the Peer node. After receiving the data, the Peer node can decrypt the metadata to prepare for subsequent authorized access.

8. The system according to claim 5, characterized in that The IPFS cluster needs to select several relatively active nodes based on performance, and only the selected nodes can receive metadata shards and generate fingerprint hashes.

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