Data security circulation method based on block chain in hierarchical novel cloud manufacturing application scene

Abstract

The invention discloses a block chain-based data security circulation method in a hierarchical novel cloud manufacturing application scene. In view of data security problems such as data leakage, data tampering and difficult data tracing in data circulation and data storage processes of a novel cloud manufacturing system, a hierarchical structure of a cloud manufacturing application scene is combined, and privacy data protection appeals are considered. The invention provides a block chain-based data security circulation method in a hierarchical novel cloud manufacturing application scene. The data security circulation system based on the block chain in the hierarchical novel cloud manufacturing application scene instantiated by the method is composed of a plurality of modules such as a block chain network, a distributed account book database, a node access approval process, a node exit approval process, a node state updating algorithm, an authorization approval mechanism, an on-chain and off-chain low-overhead storage method and the like. According to the invention, through redesign of the block chain platform service, efficient circulation of data between peer nodes and safe convergence of data between non-peer nodes are realized; the privacy data can be ensured to be available and invisible through an on-chain data ciphertext storage mode and data encryption logic; on-chain closed-loop management of data is realized through a data management component based on an intelligent contract. In conclusion, the method ensures the authenticity, integrity and confidentiality of the data in the hierarchical novel cloud manufacturing application scene, and realizes right confirmation management and hierarchical propagation of the privacy data.

Description

Technical Field

[0001] The present invention relates to data security technology of a new cloud manufacturing system. More specifically, it relates to a data security circulation method based on blockchain applicable to a hierarchical new cloud manufacturing application scenario. Background Art

[0002] In the new cloud manufacturing system, user data is collected from the edge and the end to the cloud, processed on the cloud, and then returned to the edge and the end. In this process of two-way circulation and storage of user data, there are data security issues such as data leakage, data tampering, and data traceability difficulties.

[0003] When the cloud manufacturing platform of the new cloud manufacturing system fails to resist cyber attacks, the platform's data may be at risk of leakage. There is a massive amount of data interaction in the outsourcing, outsourcing, online supply and demand docking, collaborative design and manufacturing of the new cloud manufacturing system. The administrator's authority under the traditional centralized management model is too large, and there is a possibility of human tampering with data. The lack of credibility will seriously affect the enthusiasm of users to conduct business online. Enterprise users of the new cloud manufacturing system are reluctant to disclose all supply chain transaction information, model data and other privacy information or high-value attribute data, resulting in the loss of supply chain data. The source of the data cannot be bound to the enterprise, and the model data is difficult to reuse, which makes it difficult to trace product quality and reduces the efficiency of complex business collaboration.

[0004] To achieve the above goals, existing work usually uses blockchain technology to design new cloud manufacturing systems. Blockchain technology is a distributed data circulation ledger based on specific network topology, data structure, consensus mechanism and cryptographic principles. It has the characteristics of being tamper-proof, collectively maintained, traceable and decentralized. Blockchain technology can solve problems such as data protection, trust establishment and quality traceability in new cloud manufacturing systems.

[0005] However, in a new type of cloud manufacturing system involving complex product manufacturing and the participation of large enterprises, enterprises are built on a hierarchical system with clear responsibilities and rights based on a single or multiple organizations; the cooperative relationship between enterprises is set up in a hierarchical manner, and as the level of the enterprise increases, the corresponding responsibilities and management scope become larger. Taking complex product collaborative matching as an example, the enterprise is divided into three levels: headquarters, branches, and supporting units. The headquarters is the highest level, the branches are the next level, and the supporting units are the lowest level. The data management relationship is verticalized, and enterprises at all levels are directly superior and subordinate in data management. Data converges to the next level of enterprises and is hierarchically controlled. Enterprise management and data circulation are all managed by one level at a time. The superior authorizes and approves the subordinate, and the subordinate applies to and obeys the superior, forming an efficient consensus mechanism.

[0006] The disadvantages of traditional blockchain in the application of new cloud manufacturing systems are mainly reflected in three aspects. First, the hierarchical structural contradiction. The application of new cloud manufacturing systems is often not a simple distributed manufacturer to centralized data aggregation relationship. Especially for the manufacturing of complex systems or equipment, there is often a hierarchical relationship, which is in structural contradiction with the traditional flat blockchain network. The existing blockchain nodes are node roles and information peers. There is no vertical management relationship between nodes, and the data flow is not fixed. The existing flat blockchain network architecture design does not meet the hierarchical system management data circulation requirements. Second, the data interaction mode of the traditional blockchain system is generally horizontal interaction, while in the hierarchical application scenario of the new cloud manufacturing system, it includes two data circulation relationships: horizontal interaction and vertical aggregation. Horizontal interaction refers to data sharing between non-matching nodes; vertical aggregation refers to the aggregation of data from lower nodes to upper nodes. Third, the data of the traditional blockchain system is openly and transparently stored on the chain, and the peer-to-peer network nodes can directly access all the data on the chain. In the new cloud manufacturing system, the cloud manufacturing process often corresponds to the hierarchical management process, and different institutions and different levels have different access control requirements for data. The single data storage model in traditional blockchain is difficult to adapt to the diverse and multi-demand cloud manufacturing data access control.

[0007] In short, the traditional flat blockchain network structure is not suitable for the above-mentioned hierarchical cloud manufacturing application scenarios, and the mode of storing all data in plain text on the chain is not suitable for the cloud manufacturing organization's demand for sensitive data protection in the new cloud manufacturing system scenario. In the hierarchical new cloud manufacturing application scenario, the secure circulation of blockchain-based data becomes very challenging.

[0008] To solve the above problems, different from the above existing work, this patent is applicable to the data security circulation based on blockchain in the hierarchical new cloud manufacturing application scenario. Specifically, this patent considers the existing blockchain hierarchical network design and consensus design, and focuses on the formation of blockchain node design, ledger design, contract design and storage mode design. In the hierarchical new cloud manufacturing system data security circulation system, the blockchain divides the service nodes into 4 different types according to their functions. Each node of the blockchain of the hierarchical new cloud manufacturing system data security circulation system maintains a hierarchical data ledger. This patent comprehensively considers the design of adding the review and confirmation of the superior agency, realizes the approval and confirmation of the smart contract, allows the rights and responsibilities to enter the hierarchical blockchain system through the signing and approval of the contract execution, and realizes the influence of the superior agency on the control of the key data, results and instructions of the blockchain. In addition, the patent specifically provides the access control of the nodes participating in the data security circulation, the status update of the nodes participating in the data security circulation, and the authorization and approval mechanism of the data security circulation. And considers the low-overhead storage design on the chain and off the chain, including the on-chain index encryption storage and the on-chain and off-chain storage design of the off-chain data ciphertext shard storage. In combination with the above factors, this patent constructs a data security circulation application based on blockchain in a hierarchical new cloud manufacturing application scenario. This method uses various services provided by the blockchain platform to achieve efficient data circulation between peer nodes and secure aggregation between non-peer nodes, protects data privacy through data encryption, and uses smart contracts and other means to achieve on-chain closed-loop management of data. It can ensure the authenticity, integrity and confidentiality of data in a hierarchical new cloud manufacturing application scenario, and facilitate the realization of data rights management, hierarchical propagation, and anti-destruction and persistence. Summary of the invention

[0009] The purpose of the present invention is to provide a blockchain-based data security circulation system node design, distributed ledger database design, node approval design, and on-chain and off-chain storage mode design suitable for hierarchical new cloud manufacturing application scenarios. On this basis, a blockchain-based data security circulation business application solution is given.

[0010] In order to achieve the above object, the present invention adopts the following technical solutions:

[0011] According to the first aspect of the present invention, a node design method for a data security circulation system based on blockchain for a hierarchical new cloud manufacturing application scenario is provided. The underlying layer of the data security circulation system based on blockchain relies on the blockchain system to realize the data security circulation function. The nodes in the blockchain system are the communication subjects for realizing data circulation. Multiple nodes of different types can run on the same physical server. In the data security circulation system based on blockchain for a hierarchical new cloud manufacturing application scenario, service nodes are divided into four different types according to their functions, namely: client nodes, full-function nodes, consensus nodes, and query nodes.

[0012] According to the second aspect of the present invention, a distributed ledger database design method for a hierarchical new cloud manufacturing application scenario based on blockchain for data security circulation system is provided. In the data security circulation system based on blockchain, data is securely circulated synchronously through the ledger of the underlying blockchain platform. According to the characteristics of the hierarchical relationship in the new cloud manufacturing system, the present invention uses the existing hierarchical blockchain network to establish a new cloud manufacturing system data security circulation blockchain network structure. The parent-child relationship between the upper and lower hierarchical nodes in the new cloud manufacturing system data security circulation blockchain network of the present invention represents the business hierarchical management in the new cloud manufacturing system, such as the hierarchical relationship between the overall part and subsystems and supporting places in the field of complex equipment manufacturing.

[0013] According to the third aspect of the present invention, a node approval method for a data security circulation system based on blockchain for a hierarchical new cloud manufacturing application scenario is provided. Although the data circulation of the new cloud manufacturing system implemented based on the blockchain system can bring benefits such as security, trust building between institutions, and problem tracking and tracing, the use of blockchain may also cause redundant data sharing and distribution, as well as difficulties in the system's data chain management and control of cloud manufacturing participating institutions. Typically, the correctness and availability of the results of the existing blockchain contract automation execution can only be determined by the completeness of the contract design and the security of the execution environment, and cannot be controlled by the superior institution. Therefore, it is necessary to increase the review and confirmation design of the superior institution to realize the approval and confirmation of the smart contract, so that the rights and responsibilities enter the hierarchical blockchain system through the signing and approval of the contract execution, and realize the superior institution's control over the key data, results, and instructions of the blockchain.

[0014] According to the fourth aspect of the present invention, a low-overhead storage design method for on-chain and off-chain data security circulation system based on blockchain for hierarchical new cloud manufacturing application scenarios is provided. The present invention designs an on-chain and off-chain storage design with on-chain index encryption storage and off-chain data ciphertext shard storage. The only information related to the data on the blockchain is the summary of the data and the encrypted index value. After obtaining the authorization of the data owner and the decryption key corresponding to the index ciphertext, the data recipient can decrypt and obtain the plaintext of the index value, and obtain multiple pieces of ciphertext of the off-chain data from the shard storage system based on the index value, and combine them to obtain the complete ciphertext data. The data recipient uses the decryption key corresponding to the ciphertext data to decrypt and obtain the plaintext data, thereby realizing the data circulation from the data owner to the data recipient.

[0015] According to the above aspects of the present invention, a data security circulation application based on blockchain for hierarchical new cloud manufacturing application scenarios is constructed. The data security circulation of hierarchical new cloud manufacturing application scenarios mainly uses the blockchain platform to aggregate and manage data from the bottom up, and ensures the confidentiality, integrity and availability of data in the data flow process of the new cloud manufacturing system. The hierarchical blockchain design provides hierarchical communication, hierarchical consensus, and hierarchical ledgers to ensure the authenticity, integrity and confidentiality of the data, facilitate the realization of data rights confirmation management, hierarchical propagation, and anti-destruction and stubborn storage, and provide hierarchical blockchain services for upper-level applications. Data circulation applications use various services provided by the platform to achieve efficient circulation of data between peer nodes and secure aggregation between non-peer nodes, protect data privacy through data encryption, and use smart contracts and other means to achieve closed-loop management of data on the chain.

[0016] In summary, a data security circulation method based on blockchain applicable to hierarchical new cloud manufacturing application scenarios includes the following steps:

[0017] S1. Design a data security circulation system node based on blockchain in a hierarchical new cloud manufacturing application scenario;

[0018] Preferably, the blockchain in the novel cloud manufacturing system data security circulation system divides the service nodes into four different types according to their functions, namely: client nodes, full-function nodes, consensus nodes and query nodes. The blockchain network composed of nodes is as follows: Figure 2 shown.

[0019] Among them, the client node installs a command line client program or application, representing an entity operated by the user. Only when the client node is connected to a blockchain service node can it establish communication with the blockchain network, such as submitting a data query request to any node, or submitting a transaction request to the accounting node. The full-function node can receive transaction applications from the client node, package the transaction into block data, and broadcast it to the blockchain network for consensus. The full-function node itself will also participate in the consensus process. After each node reaches an agreement on the order and content of the block, the data will be landed locally. The client node can query the on-chain data through the full-function node, which queries from the locally stored ledger data and returns the results to the client node. The consensus node can participate in the consensus process of the block data, verify the correctness and integrity of the data, and store the block data in the local ledger after the blockchain nodes in the network reach a consensus. At the same time, the consensus node can receive data query applications from the client node and return the query results. The query node cannot receive transaction applications, nor does it participate in the data consensus process. It is only used to query on-chain data. By broadcasting the "next block" request message to other nodes, the block information on the chain is obtained one by one, thereby saving a complete copy of the ledger data. Organizations represent the infrastructure of the blockchain composed of different types of nodes and ensure the operation and security of the blockchain network. In the hierarchical new cloud manufacturing scenario, the first-level blockchain represents the blockchain composed of the first-layer nodes, the second-level blockchain represents the blockchain composed of the second-layer nodes, and the third-level blockchain represents the blockchain composed of the third-layer nodes. BaaS (Blockchain as a Service) is a service that embeds blockchain technology into a cloud computing platform, providing developers with a convenient, high-performance blockchain ecosystem and supporting services.

[0020] S2. Design a hierarchical new cloud manufacturing application scenario based on blockchain-based data security circulation system distributed ledger database;

[0021] Preferably, X represents a system node, i represents the level of the node in the system, j, f and g represent the position of the node in the same level, k, o and l represent the sibling nodes of a node, a, b and c represent three nodes in the same level respectively, and z represents a node in a level. Then the system can be described as follows: The i-th level node X in the system i,j ,X i,j+1 ,…,X i,j+k is the node X at the i+1th layer i+1,a The child nodes are formally described as {X i,j ,X i,j+1 ,…,X i,j+k}∈X i+1,a ; Node X at layer i+1 i+1,a ,X i+1,b,X i+1,c is the node X at layer i+2 i+2,z The child nodes are formally described as {X i+1,a ,X i+1,b ,X i+1,c}∈X i+2,z ; Node X i,j ,…,X i,j+k Have the same parent node X i+1,a , are sibling nodes, and those without a common direct parent node are non-sibling nodes. The hierarchical blockchain consensus process of the new cloud manufacturing system includes a two-stage approach of downward consensus process and upward consensus process. The i+1th layer node achieves consensus with the corresponding node of the ith layer through the downward consensus process; the i+1th layer node completes consensus with the i+2th layer node through the upward consensus process.

[0022] Each node in the hierarchical data ledger of the data security circulation system based on blockchain in the hierarchical new cloud manufacturing application scenario maintains a hierarchical data account book. In the blockchain network proposed in the present invention, the data consensus process occurs between the parent node and its child nodes; after the consensus is completed, the child node will land the data and record it in the account book. If the parent node does not exist, the data after consensus will also be recorded in the local account book; otherwise, the parent node will continue to reach a consensus on the data between its sibling nodes and its parent node. Thus, a set of ledgers is maintained between each sibling node, and a set of ledgers is maintained between the ancestor nodes (top-level nodes), and the data range of the ledger is gradually expanded from low-level nodes to high-level nodes.

[0023] The blockchain ledger is a hierarchical linked ledger structure, which is a ledger formed between brother nodes at each layer after consensus. Ledger association is the data association relationship between ledgers. The high-level ledger data contains the low-level child node ledger data. The hierarchical blockchain ledger structure of the new cloud manufacturing system is as follows: Figure 3 The ledger structure is described as follows: the i+1th layer node X i+1,a , Node X i+1,b Node X i+1,c Jointly maintain the ledger i+1,abc (t), the i-th layer node {X i,j ,X i,j+1 ,…,X i,j+k Maintaining the ledger ij (t), node {X i,f ,X i,f+1 ,…,X i,f+o Maintaining the ledger if (t), node {X i,g ,X i,g+1 ,…,X i,g+l Maintaining the ledger ig(t). The i+1th layer ledger data contains the data of the ith layer ledger, that is: the i+1th layer ledger Ledger i+1,abc (t) The data contains the i-th layer ledger ij (t), Ledger if (t) and Ledger ig (t) data.

[0024] S3. Design a node approval method for data security circulation system based on blockchain for hierarchical new cloud manufacturing application scenarios;

[0025] The blockchain node admission mechanism is set up to prevent unnecessary nodes from joining the network. In addition, in order to prevent the offline and deletion of nodes from affecting the security and stability of the blockchain network, it is necessary to set up a node admission control mechanism and a node status detection mechanism to prevent data security incidents caused by some nodes being offline. The specific steps include the following:

[0026] Preferably, in view of the need for corresponding access control of blockchain networks at multiple levels and between each level in the hierarchical new cloud manufacturing application scenario based on the blockchain data security circulation system, a node access control contract is designed to implement an authorization control mechanism for nodes joining and exiting the blockchain network.

[0027] Preferably, the node admission control process is as follows: the node identity needs to be verified before admission, and only nodes with legal certificates are allowed to join the blockchain network. Regardless of whether the startup is successful or not, the startup operation information of the node needs to be reported to its parent node. The node admission control request is initiated by the node end, and then the startup verification method of the admission control contract is executed to verify the legality and validity of the node's identity certificate. If the verification passes, the node is allowed to be started; otherwise, the node is refused to be started. The contract execution result is sent to the management end, and the management end selects the node to be uploaded to the chain to record the startup information of the node. The node admission control process is as follows: Figure 4 shown.

[0028] Preferably, the node exit control process is as follows: the management end selects a fully functional node from the parent node of the node that is operating normally, and then reports the node startup information to the node. The node executes the data chain method of the exit control contract and finally uploads the information to the chain. The exit control contract is deployed in two parts. The startup verification method part is a built-in system contract and can be called directly; the data chain method part needs to be manually deployed before it can be called.

[0029] Before the node is allowed to exit, it is necessary to determine whether the node's exit from the network will affect the consensus process of other nodes in the network, thereby causing data to fail to converge normally. Regardless of whether the node can exit the network, the node's stop operation information will be reported to its parent node. Figure 5 Count hie (X i,j ) means dividing by X i,j In addition, the number of consensus nodes with the same hierarchical attributes as this node; Count father (X i,j ) represents node X i,j The number of parent nodes (assuming that the node {X i,j , X i,j+1 ...X i,j+k} has a level attribute value of abc, then the node {X i+1,m , X i+1,m+1 ...X i+1,m+o} is {X i,j , X i,j+1 ...X i,j+k}'s parent node, {X i,j , X i,j+1 ...X i,j+k} is {X i+1,m , X i+1,m+1 ...X i+1,m+o}child nodes); Count uc (X i,j ) means dividing by X i,j Outside, nodes_up X(i,j) The number of nodes that can participate in consensus; Count son (X i,j ) represents node X i,j The number of child nodes; Count dc (X i,j ) means dividing by X i,j Outside, nodes_down X(i,j) The number of nodes that can participate in consensus.

[0030] The node exit control is initiated by the platform management end. The user initiates a node stop request in the management point interface, and then the management end determines whether the stop of the node will affect the consensus of subsequent data of other nodes in the layer and the transmission of lower-layer data. First, it is determined whether there is a consensus node with hierarchical attributes consistent with the node in the layer after the node stops. If not, refuse to stop the node; otherwise, proceed to the next round of judgment. Then determine whether the node has a parent node. If so, it is necessary to determine whether its peer nodes can still complete upward consensus after the node stops. If not, refuse to stop the node; if it can or there is no parent node, proceed to the next round of judgment. Next, determine whether the child nodes of the node can still complete upward consensus after the node stops. If so, agree to stop the node, otherwise refuse to stop the node. The node stop result is reported to the management end. The management end selects a fully functional node from the parent node of the node that is operating normally, and then reports the node stop information to the node. The node executes the data chain method of the exit control contract to chain the information. The node exit control process is as follows Figure 5 shown.

[0031] Preferably, in view of the node status update requirements in the daily operation of the data security circulation system based on the blockchain in the hierarchical new cloud manufacturing application scenario, a contract is designed to record the status of the node on the blockchain. All nodes need to periodically call the node status update contract to update their own attribute status, and the node's parent node can view its latest attribute status at any time.

[0032] After the node is successfully started, it executes the scheduled task to regularly report its own status information to the parent node. The specific process is: the node sends information such as name, IP (Internet Protocol) address, hierarchical attributes and current status to the management end. After receiving the status information, the management end selects a fully functional node from the parent node of the node that is operating normally; then calls the parent node function interface to store <node status information, current time> into the new node status set newMap; finally, the parent node executes the data chain method of the node status information update contract to chain the child node status information. The new node status set newMap and the old node status set oldMap are the new and old node status sets, consisting of key-value pairs, where the "key" is the node and its status information, and the "value" is the current system time. The parent node filters the abnormal status of the node based on the information of the above two sets, and the hierarchical new cloud manufacturing application scenario is based on the data security circulation of blockchain-based participating node status update algorithms such as Figure 6 shown.

[0033] Preferably, in view of the requirement that the upper node must confirm and authorize before operations such as data query and modification of lower-level nodes in the data security circulation system based on blockchain in the hierarchical new cloud manufacturing application scenario, the process of authorization and approval contract is as follows: the user initiates a business application through the application system, and after the application system performs corresponding data processing, it calls the smart contract to upload the business application information to the chain. The approving user of the business logs in to the application system, queries the application information on the chain, and approves it according to the business process. The approval opinion is stored on the blockchain through the smart contract, and the status of the application behavior is updated at the same time. The user queries the business status through the application system. If it has been approved, the subsequent business can continue according to the approval result. The authorization and approval process of the data security circulation system based on blockchain in the hierarchical new cloud manufacturing application scenario is as follows: Figure 7 shown.

[0034] S4. Design a hierarchical new cloud manufacturing application scenario based on blockchain data security circulation system with low-overhead storage methods on and off the chain;

[0035] Preferably, in view of the requirements of data security, convenience, and confirmation of rights for the data circulation system based on blockchain in the hierarchical new cloud manufacturing application scenario, the on-chain and off-chain storage design process of on-chain index encryption storage and off-chain data ciphertext shard storage is specifically as follows: the information related to the data on the blockchain is only the summary of the data and the encrypted index value. After obtaining the authorization of the data owner and the decryption key corresponding to the index ciphertext, the data recipient can decrypt and obtain the plaintext of the index value, and obtain multiple pieces of ciphertext of the off-chain data from the shard storage system based on the index value, and combine them to obtain the complete ciphertext data. The data recipient uses the decryption key corresponding to the ciphertext data to decrypt and obtain the plaintext data, thereby realizing the data circulation from the data owner to the data recipient.

[0036] S5. Realize hierarchical new cloud manufacturing application scenarios based on blockchain data security circulation applications.

[0037] Preferably, in the hierarchical new cloud manufacturing application scenario, the participants include data providers and data receivers. Different participants are connected to the underlying blockchain network through a security suite. The data provider completes data uploading and transmission by calling the on-chain smart contract and completes data circulation through the synchronization of the ledger. The data receiver also completes the on-chain data reading through the smart contract call, thereby realizing the sharing of cloud manufacturing production business data. In the specific implementation process, the data security circulation application disassembles and repackages the received cloud manufacturing business data, packages it into a standard data packet, and uploads it to the data security circulation blockchain network. When it is necessary to read the on-chain data, the hash value of the data or file is found through the transaction hash, and it is returned to the data reader in the format of a standardized data packet, meeting the data security flow requirements of different business applications. The schematic diagram of the implementation of the data security circulation application based on blockchain in the hierarchical new cloud manufacturing application scenario is shown in the figure. Figure 8 shown.

[0038] The beneficial effects of the present invention are as follows:

[0039] The technical solution described in the present invention can improve the challenging problem of secure data circulation based on blockchain in hierarchical new cloud manufacturing application scenarios. Aiming at the needs of enterprise users of new cloud manufacturing systems for secure data exchange and circulation, trust establishment, and resource sharing, as well as the flat structure of traditional blockchain networks that are not suitable for hierarchical system requirements and cannot meet the problem of secure data circulation in new cloud manufacturing system multi-layered system cloud manufacturing application scenarios, the present invention proposes a data security circulation technology based on blockchain in hierarchical new cloud manufacturing application scenarios, and provides blockchain node design, account book design, node approval design, and storage mode design. The invention has the advantages of strong universality, safety and reliability, resource saving, and adaptability to hierarchical management systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The specific embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings;

[0041] Figure 1 The flowchart of data security circulation based on blockchain in the hierarchical new cloud manufacturing application scenario is shown.

[0042] Figure 2 The diagram shows the composition of the blockchain network in the hierarchical new cloud manufacturing application scenario.

[0043] Figure 3 The blockchain ledger structure diagram of the data security circulation system in the hierarchical new cloud manufacturing application scenario is shown.

[0044] Figure 4 The flowchart of blockchain node access control of data security circulation system in hierarchical new cloud manufacturing application scenario is shown.

[0045] Figure 5 The figure shows the blockchain node access control flow chart of the data security circulation system in the hierarchical new cloud manufacturing application scenario.

[0046] Figure 6 The blockchain participating node status update algorithm of the data security circulation system in the hierarchical new cloud manufacturing application scenario is shown.

[0047] Figure 7 The authorization and approval flowchart of the data security circulation system based on blockchain in the hierarchical new cloud manufacturing application scenario is shown.

[0048] Figure 8 The schematic diagram of the implementation principle of data security circulation application based on blockchain in the hierarchical new cloud manufacturing application scenario is shown. DETAILED DESCRIPTION

[0049] In order to more clearly illustrate the present invention, the present invention is further described below in conjunction with preferred examples and accompanying drawings. Similar components in the accompanying drawings are represented by the same reference numerals. It should be understood by those skilled in the art that the content specifically described below is illustrative rather than restrictive, and should not be used to limit the scope of protection of the present invention.

[0050] like Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 and Figure 8 As shown, the present invention discloses a data security circulation method based on blockchain applicable to a hierarchical new cloud manufacturing application scenario, comprising the following steps:

[0051] S1. Design a data security circulation system node based on blockchain in a hierarchical new cloud manufacturing application scenario;

[0052] In the blockchain-based data security circulation system proposed in this patent, the client node installs a command line client program or application, representing an entity operated by the user. Only when the client node is connected to a blockchain service node can it establish communication with the blockchain network, such as submitting a data query request to any node, or submitting a transaction request to the accounting node. The full-function node can receive transaction applications from the client node, package the transaction into block data, and broadcast it to the blockchain network for consensus. The full-function node itself will also participate in the consensus process, and after each node reaches an agreement on the order and content of the block, the data will be landed locally. The client node can query the on-chain data through the full-function node, which queries from the locally stored ledger data and returns the results to the client node. The consensus node can participate in the consensus process of the block data, verify the correctness and integrity of the data, and store the block data in the local ledger after the blockchain nodes in the network reach a consensus. At the same time, the consensus node can receive data query applications from the client node and return the query results. The query node cannot receive transaction applications, nor does it participate in the data consensus process, and is only used to query on-chain data. By broadcasting the "next block" request message to other nodes, the block information on the chain is obtained one by one, thereby saving a complete copy of the ledger data. Organizations represent the infrastructure of the blockchain composed of different types of nodes and ensure the operation and security of the blockchain network. In the hierarchical new cloud manufacturing scenario, the first-level blockchain represents the blockchain composed of the first-layer nodes, the second-level blockchain represents the blockchain composed of the second-layer nodes, and the third-level blockchain represents the blockchain composed of the third-layer nodes. BaaS (Blockchain as a Service) is a service that embeds blockchain technology into a cloud computing platform, providing developers with a convenient, high-performance blockchain ecosystem and supporting services.

[0053] S2. Design a distributed ledger database for a data security circulation system based on blockchain in a hierarchical new cloud manufacturing application scenario;

[0054] X represents a system node, i represents the level of the node in the system, j, f and g represent the position of the node in the same level, k, o and l represent the sibling nodes of a node, a, b and c represent three nodes in the same level respectively, and z represents a node in a level. i,j ,X i,j+1 ,…,X i,j+k is the node X at the i+1th layer i+1,a The child nodes are formally described as {X i,j ,X i,j+1 ,…,X i,j+k}∈X i+1,a ; Node X at layer i+1 i+1,a ,Xi+1,b ,X i+1,c is the node X at layer i+2 i+2,z The child nodes are formally described as {X i+1,a ,X i+1,b ,X i+1,c}∈X i+2,z ; Node X i,j ,…,X i,j+k Have the same parent node X i+1,a , are sibling nodes, and those without a common direct parent node are non-sibling nodes. The hierarchical blockchain consensus process of the new cloud manufacturing system includes a two-stage approach of downward consensus process and upward consensus process. The i+1th layer node achieves consensus with the corresponding node of the ith layer through the downward consensus process; the i+1th layer node completes consensus with the i+2th layer node through the upward consensus process.

[0055] Each node of the data security circulation system based on blockchain in the hierarchical new cloud manufacturing application scenario maintains a hierarchical data ledger. In an ordinary blockchain network, all service nodes are completely equal and jointly maintain a set of data ledgers. In a hierarchical blockchain network, there is a hierarchical relationship of data flow between nodes mapped by vertical relationships in management, thereby forming a hierarchical ledger. In the hierarchical blockchain network proposed in the present invention, the data consensus process occurs between the parent node and its child nodes; after the consensus is completed, the child node lands the data and records it in the ledger. If the parent node does not have a parent node, the data after consensus is also recorded in the local ledger; otherwise, the parent node continues to reach consensus on the data in the network of its sibling nodes and its parent node. As a result, a set of ledgers is maintained between each sibling node, and the ancestor node (top-level node) maintains a set of ledgers, and the data range of the ledger is gradually expanded from low-level nodes to high-level nodes.

[0056] The hierarchical blockchain ledger is a hierarchical linked ledger structure, which is a ledger formed between brother nodes at each layer after consensus. Ledger association is the data association relationship between ledgers. The high-level ledger data contains the low-level child node ledger data. The ledger structure is described as follows: The i+1th layer node X i+1,a Node X i+1,b Node X i+1,c Jointly maintain the ledger i+1,abc (t), the i-th layer node {X i,j ,X i,j+1 ,…,X i,j+k Maintaining the ledger ij (t), node {X i,f ,X i,f+1 ,…,X i,f+o Maintaining the ledger if (t), node {X i,g ,X i,g+1 ,…,Xi,g+l Maintaining the ledger ig (t). The i+1th layer ledger data contains the data of the ith layer ledger, that is: the i+1th layer ledger Ledger i+1,abc (t) The data contains the i-th layer ledger ij (t), Ledger if (t) and Ledger ig (t) data.

[0057] S3. Design a node approval method for data security circulation system based on blockchain in a hierarchical new cloud manufacturing application scenario;

[0058] The blockchain node access mechanism is set up to prevent unnecessary nodes from joining the network. In addition, in order to prevent the offline and deletion of nodes from affecting the security and stability of the blockchain network, it is necessary to set up a node access control mechanism and a node status detection mechanism to prevent data security incidents caused by the offline of some nodes. The specific steps include the following: In view of the need for corresponding access control of multiple levels and blockchain networks between each level in the data security circulation system based on blockchain in the hierarchical new cloud manufacturing application scenario, the node access control contract is designed to realize the authorization control mechanism for nodes joining and exiting the blockchain network.

[0059] The specific process of node access control is as follows: the node identity needs to be verified before admission, and only nodes with legal certificates are allowed to join the blockchain network. Regardless of whether the startup is successful or not, the startup operation information of the node needs to be reported to its parent node. The node access control request is initiated by the node end, and then the startup verification method of the access control contract is executed to verify the legitimacy and validity of the node's identity certificate. If the verification passes, the node is allowed to be started; otherwise, the node is refused to be started. The contract execution result is sent to the management end, and the management end selects the node to be chained to record the startup information of the node.

[0060] The specific process of node exit control is as follows: the management end selects a fully functional node from the parent node of the node that is operating normally, and then reports the node startup information to the node. The node executes the data chain method of the exit control contract and finally uploads the information to the chain. The exit control contract is deployed in two parts. The startup verification method part is a built-in system contract and can be called directly; the data chain method part needs to be manually deployed before it can be called.

[0061] Before exiting the network, it is necessary to determine whether the node's exit from the network will affect the consensus process of other nodes in the network, thereby causing data to fail to converge normally. Regardless of whether the node can exit the network, the node's stop operation information will be reported to its parent node. hie (Xi,j ) means dividing by X i,j In addition, the number of consensus nodes with the same hierarchical attributes as this node; Count father (X i,j ) represents node X i,j The number of parent nodes (assuming that the node {X i,j , X i,j+1 ...X i,j+k} has a level attribute value of abc, then the node {X i+1,m , X i+1,m+1 ...X i+1,m+o} is {X i,j , X i,j+1 ...X i,j+k}'s parent node, {X i,j , X i,j+1 ...X i,j+k} is {X i+1,m , X i+1,m+1 ...X i+1,m+o}child nodes); Count uc (X i,j ) means dividing by X i,j Outside, nodes_up X(i,j) The number of nodes that can participate in consensus; Count son (X i,j ) represents node X i,j The number of child nodes; Count dc (X i,j ) means dividing by X i,j Outside, nodes_down X(i,j) The number of nodes that can participate in consensus.

[0062] The node exit control is initiated by the platform management end. The user initiates a node stop request in the management point interface, and then the management end determines whether the node will affect the consensus of subsequent data of other nodes in the layer and the transmission of lower-layer data after the node stops. First, it is determined whether there is a consensus node with the same hierarchical attributes as the node in the layer after the node stops. If not, the node is refused to be stopped; otherwise, the next round of judgment is carried out. Then it is determined whether the node has a parent node. If so, it is necessary to determine whether its peer nodes can still complete the upward consensus after the node stops. If not, the node is refused to be stopped; if it can or there is no parent node, the next round of judgment is entered. Next, it is determined whether the child nodes of the node can still complete the upward consensus after the node stops. If so, it is agreed to stop the node, otherwise it is refused to stop the node. The node stop result is reported to the management end. The management end selects a fully functional node from the parent node of the node that is operating normally, and then reports the node stop information to the node. The node executes the data chain method of the exit control contract to chain the information.

[0063] Aiming at the node status update requirements in the daily operation of the blockchain-based data security circulation system in the hierarchical new cloud manufacturing application scenario, a contract is designed to record the status of the node on the blockchain. All nodes need to periodically call the node status update contract to update their own attribute status, and the node's parent node can view its latest attribute status at any time. After the node is successfully started, it executes the scheduled task to regularly report its own status information to the parent node. The specific process is: the node sends information such as name, IP address, hierarchical attributes and current status to the management end. After receiving the status information, the management end selects a full-function node from the parent node of the node that is running normally; then calls the parent node function interface to store <node status information, current time> in the new node status set newMap; finally, the parent node executes the data chaining method of the node status information update contract to chain the child node status information. newMap and oldMap are the new and old node status sets, which are composed of key-value pairs, where the "key" is the node and its status information, and the "value" is the current system time. The parent node filters the abnormal node status according to the information of the above two sets.

[0064] In view of the need for confirmation and authorization by the upper node before operations such as data query and modification of lower-level nodes in the blockchain-based data security circulation system under the hierarchical new cloud manufacturing application scenario, the specific process of the authorization and approval contract is as follows: the user initiates a business application through the application system, and after the application system processes the corresponding data, it calls the smart contract to upload the business application information to the chain. The approving user of the business logs in to the application system, queries the application information on the chain, and approves it according to the business process. The approval opinion is stored on the blockchain through the smart contract, and the status of the application behavior is updated at the same time. The user queries the business status through the application system. If it has been approved, the subsequent business can continue according to the approval result.

[0065] S4. Design a low-overhead storage method for the blockchain-based data security circulation system in a hierarchical new cloud manufacturing application scenario;

[0066] In response to the requirements of data circulation security, convenience, and confirmation of rights in hierarchical new cloud manufacturing application scenarios, the on-chain and off-chain storage design process of on-chain index encrypted storage and off-chain data ciphertext shard storage is specifically as follows: the only information related to the data on the blockchain is the data summary and the encrypted index value. After obtaining the authorization of the data owner and the decryption key corresponding to the index ciphertext, the data recipient can decrypt and obtain the plaintext of the index value, and obtain multiple pieces of ciphertext of the off-chain data from the shard storage system based on the index value, and combine them to obtain the complete ciphertext data. The data recipient uses the decryption key corresponding to the ciphertext data to decrypt the data plaintext, realizing the data flow from the data owner to the data recipient.

[0067] S5. Realize the secure circulation of data based on blockchain in hierarchical new cloud manufacturing application scenarios.

[0068] In the hierarchical new cloud manufacturing application scenario, the specific steps are as follows: the data security circulation application disassembles and repackages the received cloud manufacturing business data, packages it into a standard data packet, and uploads it to the blockchain network for data security circulation. When it is necessary to read the data on the chain, the hash value of the data or file is found through the transaction hash, and it is returned to the data reader in the format of a standardized data packet to meet the data security circulation requirements of different business applications.

[0069] The data circulation application is connected to the hierarchical blockchain platform, which requires the planning of platform resources. All subsequent data-related operations will be managed on the chain. First, the demand personnel propose the establishment of the business chain and the construction requirements of each cloud manufacturing node according to the specific business, providing a reference for the deployment of the underlying blockchain service of the data circulation application and providing guarantee for the normal operation of the subsequent application. Then, the system maintenance personnel deploy the hierarchical blockchain platform and start the platform service. Then, each node user logs in to the hierarchical blockchain platform, creates a node of the corresponding type and starts the node service. After the above preparations are completed, the deployment of the data circulation application can be carried out, the corresponding system configuration of the application can be modified according to the deployment environment, and then the application system can be started. Next, each node user can log in to the application system and start each data circulation business. The blockchain service will record the business data, user behavior and other information in the business operation process on the chain to support the data circulation management function of the application. The system administrator can perform data audit and chain audit operations to audit data records, data maintenance records, user data usage records, user behavior records and other data.

[0070] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not limitations on the implementation methods of the present invention. For ordinary technicians in the relevant field, other different forms of changes or modifications can be made based on the above description. It is impossible to list all the implementation methods here. All obvious changes or modifications derived from the technical solution of the present invention are still within the protection scope of the present invention.

Claims

1. According to the data security circulation method based on blockchain in the hierarchical new cloud manufacturing application scenario, it is characterized by: First, we design the data security circulation system nodes based on blockchain. The blockchain network composition is shown in Figure 2. Among them, the client node installs a command line client program or application, representing an entity operated by the user. Only when the client node is connected to a certain blockchain service node can it establish communication with the blockchain network, such as submitting a data query request to any node, or submitting a transaction request to the accounting node. The full-function node can receive transaction applications from the client node, package the transaction into block data, and broadcast it to the blockchain network for consensus. The full-function node itself will also participate in the consensus process. After each node reaches an agreement on the order and content of the block, the data will be landed locally. The client node can query the on-chain data through the full-function node. The full-function node queries from the locally stored ledger data and returns the results to the client node. The consensus node can participate in the consensus process of the block data, verify the correctness and integrity of the data, and store the block data in the local ledger after the blockchain nodes in the network reach a consensus. At the same time, the consensus node can receive data query applications from the client node and return the query results. The query node cannot receive transaction applications, nor does it participate in the data consensus process. It is only used to query on-chain data. By broadcasting "nextblock" request messages to other nodes, the block information on the chain is obtained one by one, thereby saving a complete copy of the ledger data. Organizations represent the infrastructure of the blockchain composed of different types of nodes and ensure the operation and security of the blockchain network. In the hierarchical new cloud manufacturing scenario, the first-level blockchain represents the blockchain composed of the first-layer nodes, the second-level blockchain represents the blockchain composed of the second-layer nodes, and the third-level blockchain represents the blockchain composed of the third-layer nodes. BaaS (Blockchain as a Service), that is, "Blockchain as a Service", is a service that embeds blockchain technology into a cloud computing platform, providing developers with a convenient, high-performance blockchain ecosystem and supporting services.

2. According to claim 1, the data security circulation method based on blockchain in the hierarchical new cloud manufacturing application scenario is characterized in that: Design a distributed ledger database for data security circulation system based on blockchain, and the blockchain ledger structure is shown in Figure 3. In which, X represents the system node, i represents the level of the node in the system, j, f and g represent the position of the node in the same level, k, o and l represent the sibling nodes of a node, a, b and c represent three nodes in the same level respectively, and z represents a node in a level. Then the system can be described as follows. i,j ,X i,j+1 ,…,X i,j+k is the node X at the i+1th layer i+1,a The child nodes are formally described as {X i,j ,X i,j+1 ,…,X i,j+k }∈X i+1,a ; Node X at layer i+1 i+1,a ,X i+1,b ,X i+1,c is the node X at layer i+2 i+2,z The child nodes are formally described as {X i+1,a ,X i+1,b ,X i+1,c }∈X i+2,z ; Node X i,j ,…,X i,j+k Have the same parent node X i+1,a , are sibling nodes, and those without a common direct parent node are non-sibling nodes. The hierarchical blockchain consensus process of the new cloud manufacturing system includes a two-stage approach of downward consensus process and upward consensus process. The i+1th layer node achieves consensus with the corresponding node of the ith layer through the downward consensus process; the i+1th layer node completes consensus with the i+2th layer node through the upward consensus process. Each node in the blockchain-based data security circulation system maintains a hierarchical data account book. In a hierarchical blockchain network, there is a hierarchical relationship of data flow between nodes mapped by a vertical relationship in management, thereby forming a hierarchical account book. In the hierarchical blockchain network proposed in the present invention, the data consensus process occurs between the parent node and its child nodes; after the consensus is completed, the child node lands the data and records it in the account book. If the parent node does not have a parent node, the data after consensus is also recorded in the local account book; otherwise, the parent node continues to reach a consensus on the data between its sibling node and its parent node network. Thus, a set of account books is maintained between each sibling node, and a set of account books is maintained by the ancestor node (top node), and the data range of the account book is gradually expanded from the low-level node to the high-level node. The blockchain account book is a hierarchical association account book structure, which is an account book formed between the sibling nodes of each layer after consensus. Account book association is a data association relationship between account books, and the high-level account book data contains the low-level child node account book data. In Figure 3, the node X at the i+1th layer i+1,a , Node X i+1,b , Node X i+1,c Jointly maintain the ledger i+1,abc (t), the i-th layer node {X i,j ,X i,j+1 ,…,X i,j+k Maintaining the ledger ij (t), node {X i,f ,X i,f+1 ,…,X i,f+o Maintaining the ledger if (t), node {X i,g ,X i,g+1 ,…,X i,g+l Maintaining the ledger ig (t). The i+1th layer ledger data contains the data of the ith layer ledger, that is: the i+1th layer ledger Ledger i+1,abc (t) The data contains the i-th layer ledger ij (t), Ledger if (t) and Ledger ig (t) data.

3. According to claim 1, the data security circulation method based on blockchain in the hierarchical new cloud manufacturing application scenario is characterized in that: Design the node access mechanism and access control contract of the blockchain-based data security circulation system under the hierarchical new cloud manufacturing application scenario, and implement the authorization control mechanism for nodes to join and exit the blockchain network to prevent unnecessary nodes from not joining the network. The node access control process is as follows: the node identity needs to be verified before admission, and only nodes with legal certificates are allowed to join the blockchain network. Regardless of whether the startup is successful or not, the startup operation information of the node needs to be reported to its parent node. The node access control request is initiated by the node end, and then the startup verification method of the access control contract is executed to verify the legitimacy and validity of the node's identity certificate. If the verification passes, the node is allowed to be started; otherwise, the node is refused to be started. The contract execution result is sent to the management end, and the management end selects the node to record the startup information of the node on the chain. The specific process is shown in Figure 4.

4. The data security circulation method based on blockchain in the hierarchical new cloud manufacturing application scenario according to claim 3 is characterized in that: Design a node exit control mechanism and exit control contract for a data security circulation system based on blockchain in a hierarchical new cloud manufacturing application scenario, implement an authorization control mechanism for nodes when they exit the blockchain network, and prevent node offline, deletion, and other operations from affecting the security and stability of the blockchain network. The specific node exit control process is as follows: the management end selects a full-function node from the parent node of the node that is operating normally, and then reports the node startup information to the node. The node executes the data chain method of the exit control contract and finally uploads the information to the chain. The exit control contract is deployed in two parts. The startup verification method part is a built-in system contract that can be called directly; the data chain method part needs to be manually deployed before it can be called. The specific process is shown in Figure 5. Before exiting the network, it is necessary to determine whether the node’s exit from the network will affect the consensus process of other nodes in the network, thereby causing data to fail to converge normally. Regardless of whether the node can exit the network, the node’s stop operation information will be reported to its parent node. hie (X i,j ) means dividing by X i,j In addition, the number of consensus nodes with the same hierarchical attributes as this node; Count father (X i,j ) represents node X i,j The number of parent nodes (assuming that the node {X i,j , X i,j+1 ...X i,j+k } has a level attribute value of abc, then the node {X i+1,m , X i+1,m+1 ...X i+1,m+o } is {X i,j , X i,j+1 ...X i,j+k }'s parent node, {X i,j , X i,j+1 ...X i,j+k } is {X i+1,m , X i+1,m+1 ...X i+1,m+o }child nodes); Count uc (X i,j ) means dividing by X i,j Outside, nodes_up X(i,j) The number of nodes that can participate in consensus; Count son (X i,j ) represents node X i,j The number of child nodes; Count dc (X i,j ) means dividing by X i,j Outside, nodes_down X(i,j) The number of nodes that can participate in consensus. The node exit control is initiated by the platform management end. The user initiates a node stop request in the management point interface, and then the management end determines whether the node stop will affect the consensus of subsequent data of other nodes in the layer and the transmission of lower-layer data. First, it is determined whether there is a consensus node with the same hierarchical attributes as the node in the layer after the node is stopped. If not, the node is refused to be stopped; Otherwise, proceed to the next round of judgment. Then determine whether the node has a parent node. If so, it is necessary to determine whether its peer nodes can still complete the upward consensus after the node stops. If not, refuse to stop the node; if it can or there is no parent node, proceed to the next round of judgment. Next, determine whether the child nodes of the node can still complete the upward consensus after the node stops. If so, agree to stop the node, otherwise refuse to stop the node. The node stop result is reported to the management end. The management end selects a fully functional node from the parent node of the node that is running normally, and then reports the node stop information to the node. The node executes the data chain method of the permission control contract to chain the information.

5. According to claim 4, the data security circulation method based on blockchain in the hierarchical new cloud manufacturing application scenario is characterized in that: Design a node status detection mechanism for the data security circulation system based on blockchain in the hierarchical new cloud manufacturing application scenario, design a contract for recording the status of the node on the blockchain, and implement the call of the node status update contract in all node cycles to update its own attribute status. The node's parent node can view its latest attribute status at any time. The specific process is: the node sends information such as name, IP (Internet Protocol) address, hierarchical attributes and current status to the management end. After receiving the status information, the management end selects a full-function node from the parent node of the node that is running normally; then calls the parent node function interface to store <node status information, current time> in the node status set newMap; finally, the parent node executes the data chaining method of the node status information update contract to chain the child node status information. Both the new node status set newMap and the old node status set oldMap are node status sets, consisting of key-value pairs, where the "key" is the node and its status information, and the "value" is the current system time. The parent node filters the abnormal status of nodes according to the information of the above two sets. The specific algorithm is shown in Figure 6.

6. The data security circulation method based on blockchain in the hierarchical new cloud manufacturing application scenario according to claim 5 is characterized in that: Design a blockchain-based data security circulation system authorization and approval mechanism under the hierarchical new cloud manufacturing application scenario to realize the need for confirmation and authorization by the upper node before the lower node data query, modification and other operations. The specific process is: the user initiates a business application through the application system, and after the application system processes the corresponding data, it calls the smart contract to upload the business application information to the chain. The approving user of the business logs in to the application system, queries the application information on the chain, and approves it according to the business process. The approval opinion is stored on the blockchain through the smart contract, and the status of the application behavior is updated at the same time. The user queries the business status through the application system. If it has been approved, the subsequent business can continue according to the approval result. The specific process is shown in Figure 7.

7. The data security circulation method based on blockchain in the hierarchical new cloud manufacturing application scenario according to claim 6 is characterized in that: Design a low-overhead storage method for data security circulation on and off the chain based on blockchain in hierarchical new cloud manufacturing application scenarios. Specifically, in response to the requirements for data circulation security, convenience, and confirmation of rights in hierarchical new cloud manufacturing application scenarios, the on-chain index encryption storage and off-chain data ciphertext shard storage on the chain are designed as follows: The only information related to the data on the blockchain is the data summary and the encrypted index value. After obtaining the authorization of the data owner and the decryption key corresponding to the index ciphertext, the data recipient can decrypt and obtain the index value plaintext, and obtain multiple pieces of off-chain data ciphertext from the shard storage system based on the index value, and combine them to obtain the complete ciphertext data. The data recipient uses the decryption key corresponding to the ciphertext data to decrypt the data plaintext, realizing the data circulation from the data owner to the data recipient.

8. The data security circulation method based on blockchain in the hierarchical new cloud manufacturing application scenario according to claim 7 is characterized in that: The data security circulation application based on blockchain in the hierarchical new cloud manufacturing application scenario is as follows: in the hierarchical new cloud manufacturing application scenario, different participants access the underlying blockchain network through the security suite, the data provider completes the data chain and transmission by calling the on-chain smart contract, completes the data circulation through the synchronization of the ledger, and the receiver also completes the on-chain data reading through the smart contract call, realizing the sharing of cloud manufacturing production business data. In the specific implementation process, the data security circulation application disassembles and repackages the received cloud manufacturing business data, packages it into a standard data package, and chains it in the data security circulation blockchain network. When it is necessary to read the on-chain data, the hash value of the data or file is found through the transaction hash, and it is returned to the data reader in the format of a standardized data package, which meets the data security circulation requirements of different business applications. The specific process is shown in Figure 8.

Images