BIM data version control and tracking method based on block chain technology

Abstract

The invention discloses a BIM data version control and tracking method based on a block chain technology. The method comprises the following steps of S1, block chain network construction, S2, BIM data recording and block generation, S3, chain type storage and version control, S4, intelligent contract deployment and execution, S5, copyright tracking and protection, S6, user authority management, S7, user authority management and S8, system maintenance and optimization. Through decentralization and tampering resistance of the block chain technology, the security and integrity of the BIM data are ensured. Any modification on the data can be recorded on the block chain to form an unchangeable historical record, so that the risk that the data is maliciously tampered is effectively prevented.

Description

Technical Field

[0001] The present invention relates to the field of information processing technology, and in particular to a BIM data version control and tracking method based on blockchain technology. Background Art

[0002] With the rapid development of information technology and the acceleration of digital transformation in the construction industry, Building Information Modeling (BIM) technology plays an increasingly important role in the design and construction of construction projects. BIM technology integrates the three-dimensional model, attribute information and dynamic data of the construction process of the building project, realizes information sharing and collaborative work, and significantly improves the quality and efficiency of the project. However, as BIM data becomes increasingly complex and large, how to effectively manage and control the version of BIM data and ensure the consistency and traceability of data has become an urgent problem to be solved.

[0003] At the same time, blockchain technology, with its decentralized, tamper-proof and traceable characteristics, has shown great application potential in finance, supply chain management and other fields. The introduction of blockchain technology provides a new solution for version control and tracking of BIM data. Through blockchain technology, every change of BIM data can be recorded on the chain, forming an unalterable data history record, thereby ensuring the authenticity and integrity of the data.

[0004] At present, there are some BIM data management and version control methods on the market, but most of these methods rely on centralized databases or file systems, and have problems such as poor data security, easy tampering, and poor traceability. For example, traditional BIM data management systems usually use relational databases or file servers to store BIM data, and use version control software to manage the data change history. However, this method relies on centralized storage and management. Once the central server is attacked or fails, the data may be lost or tampered with.

[0005] In addition, although some blockchain-based BIM data management methods have been proposed, most of them focus on the secure storage and sharing of data, but lack in-depth research and application in version control and tracking. Therefore, these methods still cannot fully meet the needs of BIM data version control and tracking.

[0006] The present invention proposes a BIM data version control and tracking method based on blockchain technology, aiming to solve the problems existing in the prior art in BIM data version control and tracking. The innovations of the present invention mainly include the following aspects: Deep integration of blockchain and BIM technology: This invention closely combines blockchain technology with BIM technology, and ensures the security and reliability of the version control and tracking process of BIM data through the immutability and traceability of blockchain.

[0007] Application of smart contracts: Use smart contracts to automatically execute version control and tracking logic of BIM data, reduce human intervention, and improve the automation and intelligence level of the system.

[0008] Fine-grained version control: Implement fine-grained version control of BIM data, that is, version control can be performed on individual elements or components in the BIM model rather than the entire model. This allows for more accurate tracking and management of the change history of BIM data.

[0009] Efficient data retrieval and verification: Through the distributed storage and encryption technology of blockchain, efficient retrieval and verification of BIM data can be achieved. Users can quickly query and verify the current and historical versions of BIM data to ensure the authenticity and consistency of the data.

[0010] Cross-platform data sharing: Using the decentralized nature of blockchain, cross-platform sharing of BIM data is achieved. Different participants can share and exchange BIM data on the blockchain network to improve data utilization and collaboration efficiency. Summary of the invention

[0011] The purpose of the present invention is to provide a BIM data version control and tracking method based on blockchain technology to solve the technical problems existing in the prior art.

[0012] In order to achieve the above object, the present invention adopts the following technical solutions: The present invention provides a BIM data version control and tracking method based on blockchain technology, comprising the following steps: S1. Blockchain network construction, including: S11. Select blockchain type: Select the appropriate blockchain type according to actual needs; S12. Node deployment: In the selected blockchain network, multiple nodes are deployed; the nodes include central nodes and multiple full nodes. The central node is responsible for processing the collection and packaging of BIM data, while the full node is responsible for storing the complete blockchain data and participating in the consensus process; S13. Consensus mechanism selection: Select an appropriate consensus mechanism to ensure the security and efficiency of the blockchain network; S2. BIM data recording and block generation, including: S21, BIM data collection: The central node regularly collects BIM data from various data sources; S22, data preprocessing: preprocess the collected BIM data, including data cleaning, format conversion, and compression; S23, data packaging and hash calculation: the pre-processed BIM data is packaged into data blocks according to certain rules, each data block contains multiple BIM data items, and the hash value of the entire data block is calculated, and the hash value is used to verify the integrity and uniqueness of the data block; S24, block generation: combine the data block, hash value, timestamp, and hash value information of the previous block into a new block, and attach a signature to ensure the legitimacy and immutability of the block; the newly generated block will be added to the end of the blockchain to form a chain storage structure; S3, chained storage and version control, including: S31. Blockchain synchronization: All nodes regularly synchronize the latest blockchain data from the central node to ensure that the blockchain data on all nodes remain consistent; S32. Version record: Whenever BIM data changes, the change record is added to the blockchain as a new BIM data item and a new block is generated. The generation of the new block will trigger the version control process to ensure that the version information of the BIM data is accurately recorded. S33, Historical tracing: tracing the historical versions of BIM data by querying the blockchain; S4. Smart contract deployment and execution, including: S41. Smart contract writing: Write smart contract code according to the requirements of BIM data version control; the smart contract will include version control logic, permission control logic, and trigger conditions; S42. Smart contract deployment: deploy the written smart contract to the blockchain network; S43. Trigger condition setting: setting trigger conditions for smart contracts; S44. Smart contract execution: When the triggering conditions are met, the smart contract will be automatically executed; S5. Copyright tracking and protection, including: S51, Identification embedding: When publishing a BIM model, the right holder embeds a specific digital code as an identifier into the components of the BIM model; S52. Copyright information recording: before the BIM data is uploaded to the blockchain network, the copyright information is recorded separately; S53. Copyright verification: When BIM data is accessed or used, the blockchain network will automatically perform the copyright verification process; S54. Infringement tracking: Every data transaction is accurately recorded, so the copyright owner can clearly see when, where, and by whom the BIM data is accessed or modified; S6. User rights management, including: S61. Role definition: In the BIM data version control and tracking system, different user roles need to be defined, including copyright owners, data managers, designers, and construction personnel; each role has different permissions and responsibilities to ensure the security and effectiveness of BIM data; S62. Permission allocation: According to different user roles, corresponding permissions are allocated to them; permission allocation follows the principle of least privilege, that is, only the minimum set of permissions required for users to complete their work is granted; S63, authority verification: When a user accesses BIM data, the user's authority is verified; by comparing the authority information stored on the blockchain with the user's identity information, it is determined whether the user has the right to access the BIM data; if the verification fails, the user's access request will be rejected, and the corresponding log information will be recorded for subsequent auditing; S7. User rights management, including: S71. Data encryption: Encryption technology is used to encrypt data, including the use of symmetric encryption algorithms to encrypt and decrypt data, and the use of asymmetric encryption algorithms to manage and distribute keys; S72. Access control: Ensure that only authorized users can access BIM data by assigning different permissions to different user roles and using authentication and access logging; S73. Privacy protection: Data involving user privacy is protected by using data desensitization and anonymization; S8. System maintenance and optimization, including: S81. System monitoring: Establish a system monitoring mechanism to monitor the operation status, data transaction status, and user behavior of the blockchain network in real time; timely discover potential security risks and performance bottlenecks through monitoring, and provide strong guarantees for the stable operation of the system; S82. Performance optimization: Improve the transaction processing capability and response speed of the blockchain network by optimizing the consensus algorithm, increasing the block capacity, and introducing a cache mechanism; S83. Upgrade and iteration: Continuously improve the system's functionality and performance by regularly releasing new versions, fixing known vulnerabilities, and introducing new features.

[0013] By adopting the above technical solution, the present invention has the following beneficial effects: Through the decentralization and immutability of blockchain technology, the present invention ensures the security and integrity of BIM data. Any modification to the data will be recorded on the blockchain, forming an unchangeable historical record, effectively preventing the risk of data being maliciously tampered with.

[0014] The automated management function of smart contracts makes the version control of BIM data more standardized and efficient. Each version has a unique identifier and detailed information records, which makes it easy for users to quickly find and trace. At the same time, smart contracts also ensure strict management of version permissions and prevent unauthorized data access and modification.

[0015] The decentralized nature of blockchain technology breaks the phenomenon of information silos and promotes cross-organizational data sharing and collaboration. All participants can access and verify the authenticity and integrity of BIM data in real time through the blockchain network, reducing the cost and time of information communication and improving the efficiency of collaborative work. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 Flowchart of the BIM data version control and tracking method based on blockchain technology provided by the present invention.

[0018] Figure 2 A smart contract flow chart of the BIM data version control and tracking method based on blockchain technology provided by the present invention; Figure 3 A schematic diagram of the user interface of the BIM data version control and tracking method based on blockchain technology provided by the present invention. DETAILED DESCRIPTION

[0019] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] The specific implementation of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the present invention, and is not used to limit the present invention.

[0021] Combination Figure 1-3 As shown, this embodiment provides a BIM data version control and tracking method based on blockchain technology, which includes the following steps: Step 1: Blockchain network construction: Step 1: Select blockchain type First, select the appropriate blockchain type according to actual needs. In this invention, considering the security and privacy of data, a private chain mode is adopted. Private chains allow enterprises or organizations to own and manage blockchain networks internally, ensuring that data is not maliciously accessed by external parties.

[0022] (Private chain: A blockchain network where participants need to be authorized to join. Private chains are usually used for data sharing and exchange within an organization or between specific partners.) Step 2: Node deployment In the selected blockchain network, multiple nodes are deployed. These nodes include central nodes and multiple full nodes. The central node is responsible for collecting and packaging BIM data, while the full node is responsible for storing complete blockchain data and participating in the consensus process.

[0023] Step 3: Consensus Mechanism Selection Choose a suitable consensus mechanism to ensure the security and efficiency of the blockchain network. Common consensus mechanisms include proof of work, proof of stake, and delegated proof of stake. According to actual needs, you can choose a suitable consensus mechanism to ensure data consistency and immutability.

[0024] Step 2: BIM data recording and block generation: Step 1: BIM Data Collection The central node regularly collects BIM data from various data sources (such as design software, databases, etc.). These data may include building models, component information, attribute data, etc.

[0025] Step 2: Data Preprocessing Pre-process the collected BIM data, including data cleaning, format conversion, compression, etc. Ensure that the data meets the requirements of blockchain storage and reduce storage space usage.

[0026] Step 3: Data Packaging and Hash Calculation Hash calculation, also known as hash algorithm, is a process of converting an input of any length (also called message or data) into a fixed-length output (also called hash value, hash value or summary) through a specific function. This algorithm has a wide range of applications in computer science and data security, and its characteristics include determinism, efficiency, collision resistance, tamper resistance and uniform distribution.

[0027] The pre-processed BIM data is packaged into data blocks according to certain rules. Each data block contains multiple BIM data items (BIM1, BIM2,..., BIMn), and the hash value (BIMHASH) of the entire data block is calculated. The hash value is used to verify the integrity and uniqueness of the data block.

[0028] Hash value, also known as hash value, hash value or message digest, is a function result that maps input data of any length (such as strings, files, etc.) to output data of fixed length through a hash function. It has the characteristics of determinism, unidirectionality, collision resistance and uniform distribution.

[0029] Step 4: Block Generation The data block, hash value, timestamp, hash value of the previous block and other information are combined into a new block, and a signature is attached to ensure the legitimacy and immutability of the block. The newly generated block will be added to the end of the blockchain to form a chain storage structure.

[0030] Block: It is the basic unit of blockchain, with characteristics of chain structure, data recording, security and transparency. It is generated through consensus mechanism and added to the end of blockchain after verification, providing a basis for the widespread application of blockchain technology.

[0031] Step 3: Chain storage and version control: Step 1: Blockchain synchronization Full nodes regularly synchronize the latest blockchain data from central nodes to ensure that blockchain data on all nodes remains consistent. This helps prevent data loss and tampering.

[0032] Step 2: Version Record Whenever BIM data changes, the system adds the change record as a new BIM data item to the blockchain and generates a new block. The generation of a new block will trigger the version control process to ensure that the version information of the BIM data is accurately recorded.

[0033] Step 3: Historical Tracing Users can trace the historical versions of BIM data by querying the blockchain. The chain storage structure of the blockchain allows users to start from the current block and trace back to the BIM data status at any point in time. This helps users understand the change process and reasons of BIM data.

[0034] Step 4: Smart Contract Deployment and Execution Definition of smart contract: Smart contract is the product of the combination of blockchain technology and intelligent technology. It is a computer program that defines and controls digital assets or executes contract terms in code form.

[0035] Smart contract principle: The terms and logic of the contract are written into code and deployed on the blockchain. When the conditions of the contract are met, the contract will automatically trigger the corresponding operations, such as transfer, release of assets, execution of functions, etc. These operations will be recorded on the blockchain and cannot be tampered with or reversed.

[0036] Step 1: Smart Contract Writing Write smart contract code according to the requirements of BIM data version control. Smart contracts will include version control logic, permission control logic, trigger conditions, etc.

[0037] Step 2: Smart Contract Deployment Deploy the written smart contract to the blockchain network. Once deployed, the smart contract will become part of the blockchain network and will be automatically executed when the conditions are met.

[0038] Step 3: Trigger condition setting Set trigger conditions for smart contracts. Trigger conditions can be time, specific actions, or other events. When the trigger conditions are met, the smart contract will automatically execute the version control process and add the change record to the blockchain.

[0039] Step 4: Smart Contract Execution When the trigger conditions are met, the smart contract will be automatically executed. During the execution process, the smart contract will verify the change information of BIM data, calculate the hash value, generate a new block, etc., and record the results on the blockchain.

[0040] Step 5: Copyright tracking and protection: Step 1: Embedding the logo When publishing a BIM model, the owner embeds a specific digital code as an identifier into the components of the BIM model. These identifiers can be the owner's digital signature, the spatial relationship of the components, the point sequence of the center position, etc. The embedding of the identifier can be completed through design software or special tools.

[0041] Step 2: Copyright information record Before BIM data is uploaded to the blockchain network, copyright information needs to be recorded separately. This includes key data such as copyright owner information, authorization scope, authorization period, etc. This information will be stored on the blockchain in the form of smart contracts and associated with the corresponding BIM data blocks. Smart contracts will ensure that only authorized users can access or modify BIM data, thereby protecting the rights and interests of copyright owners.

[0042] Step 3: Copyright Verification When BIM data is accessed or used, the blockchain network will automatically perform the copyright verification process. By comparing the copyright information stored on the blockchain with the visitor's permission information, the system can quickly determine whether the visitor has the right to access the BIM data. If the visitor is not authorized, the system will deny his access request and record the corresponding log information for subsequent audit.

[0043] Step 4: Infringement Tracking Due to the immutability and traceability of blockchain, every data transaction is accurately recorded, so the copyright owner can clearly see when, where, and by whom the BIM data is accessed or modified. If unauthorized use of BIM data is found, the copyright owner can track the source of the infringement through the records on the blockchain.

[0044] Step 6: User Rights Management: Step 1: Role Definition In the BIM data version control and tracking system, different user roles need to be defined, such as copyright owner, data manager, designer, construction worker, etc. Each role has different permissions and responsibilities to ensure the security and effectiveness of BIM data.

[0045] Step 2: Assign permissions Assign appropriate permissions to users based on their roles. Permission assignment should follow the principle of least privilege, that is, granting users only the minimum set of permissions necessary to complete their work. This helps reduce potential security risks and prevent data leakage and abuse.

[0046] Step 3: Permission verification When a user accesses BIM data, the system will verify the user's permissions. By comparing the permission information stored on the blockchain with the user's identity information, the system can determine whether the user has the right to access the BIM data. If the verification fails, the system will reject the user's access request and record the corresponding log information for subsequent audits.

[0047] Step 7: Security and Privacy Protection Step 1: Data encryption In order to ensure the security of BIM data during transmission and storage, advanced encryption technology is used to encrypt the data. This includes using symmetric encryption algorithms to encrypt and decrypt data, and using asymmetric encryption algorithms to manage and distribute keys. The application of encryption technology can ensure that data is not intercepted and tampered with during transmission, and prevent data leakage during storage.

[0048] Symmetric encryption algorithm: The same key is used in the encryption and decryption process, or two keys that can be easily deduced from each other can be used.

[0049] Asymmetric encryption algorithm: also known as public key encryption algorithm, is an algorithm that uses a pair of keys (public key and private key) for encryption and decryption. The principle is that when the sender wants to send encrypted information to the receiver, the sender will encrypt the information using the receiver's public key. Since the public key is public, anyone can use it to encrypt information, but only the receiver with the corresponding private key can decrypt the information.

[0050] Step 2: Access Control Establish a strict access control mechanism to manage access to BIM data in a refined manner. By assigning different permissions to different user roles, and using authentication and access logging, ensure that only authorized users can access BIM data. This helps prevent unauthorized access and data leakage risks.

[0051] Step 3: Privacy Protection While protecting the copyright of BIM data, we also need to pay attention to the privacy protection of users. Data involving user privacy can be protected by means of data desensitization and anonymization. At the same time, a complete privacy policy and data use agreement should be established to clarify the scope, purpose and restrictions of data use to ensure that the privacy rights and interests of users are fully protected.

[0052] Step 8: System maintenance and optimization: Step 1: System Monitoring Establish a system monitoring mechanism to monitor the operation status, data transaction status, user behavior, etc. of the blockchain network in real time. Through monitoring, potential security risks and performance bottlenecks can be discovered in a timely manner, providing strong guarantees for the stable operation of the system.

[0053] Step 2: Performance Optimization In order to solve the performance bottleneck problems that may exist in the blockchain network, various optimization methods are used to improve it. For example, by optimizing the consensus algorithm, increasing the block capacity, introducing a cache mechanism, etc., the transaction processing capacity and response speed of the blockchain network are improved. At the same time, according to the actual operation of the system, the system is regularly adjusted and optimized to ensure the performance and stability of the system.

[0054] Blockchain network: Blockchain network is a distributed network architecture based on blockchain technology. It is a new application model that combines multiple computer technologies such as distributed data storage, peer-to-peer transmission, consensus mechanism, and encryption algorithm.

[0055] Step 3: Upgrade and Iterate With the continuous development of BIM technology and blockchain technology, the system also needs to be continuously upgraded and iterated to meet new needs and challenges. By regularly releasing new versions, fixing known vulnerabilities, introducing new features, etc., the system's functions and performance levels are continuously improved. At the same time, we actively pay attention to industry dynamics and technology development trends to be fully prepared for the future development of the system.

[0056] Advantages or beneficial effects of the present invention: 1. Technical effect: Improved data security: Through the decentralization and immutability of blockchain technology, this invention ensures the security and integrity of BIM data. Any modification to the data will be recorded on the blockchain, forming an unchangeable historical record, effectively preventing the risk of data being maliciously tampered with.

[0057] Standardized version management: The automated management function of smart contracts makes the version control of BIM data more standardized and efficient. Each version has a unique identifier and detailed information records, which makes it easy for users to quickly find and trace. At the same time, smart contracts also ensure strict management of version permissions to prevent unauthorized data access and modification.

[0058] Improved cross-organizational collaboration efficiency: The decentralized nature of blockchain technology breaks the information island phenomenon and promotes cross-organizational data sharing and collaboration. All participants can access and verify the authenticity and integrity of BIM data in real time through the blockchain network, reducing the cost and time of information communication and improving the efficiency of collaborative work.

[0059] 2. Economic benefits: Cost reduction: By improving the efficiency and accuracy of BIM data management, the present invention helps to reduce rework and losses caused by data errors or version confusion. At the same time, the smooth cross-organizational collaboration also reduces the cost and time consumption of communication and coordination, saving valuable resources for enterprises.

[0060] Improved competitiveness: Companies that adopt blockchain-based BIM data version control and tracking methods will establish a leading image in the industry and attract more customers and partners. This will help improve the market competitiveness and brand value of the company.

[0061] 3. Social benefits: Promote digital transformation of the industry: The successful application of this invention will promote the construction industry to move towards digital transformation. By introducing advanced technologies such as blockchain, the construction industry will achieve more efficient and intelligent design, construction and management models, and enhance the competitiveness and innovation capabilities of the entire industry.

[0062] Promoting information transparency and trust building: The decentralization and immutability of blockchain technology effectively guarantee the authenticity and integrity of BIM data. This helps promote information transparency and trust building among all parties involved, reduces disputes and conflicts caused by information asymmetry, and creates a good environment for the healthy development of the construction industry.

[0063] Enhance social supervision and responsibility traceability: The blockchain-based BIM data version control and tracking method not only improves the internal data management capabilities of the enterprise, but also provides an effective supervision method for the government and social regulatory departments.

[0064] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A BIM data version control and tracking method based on blockchain technology, characterized in that: The steps include: S1. Blockchain network construction, including: S11. Select blockchain type: Select the appropriate blockchain type according to actual needs; S12. Node deployment: In the selected blockchain network, multiple nodes are deployed; the nodes include central nodes and multiple full nodes. The central node is responsible for processing the collection and packaging of BIM data, while the full node is responsible for storing the complete blockchain data and participating in the consensus process; S13. Consensus mechanism selection: Select an appropriate consensus mechanism to ensure the security and efficiency of the blockchain network; S2. BIM data recording and block generation, including: S21, BIM data collection: The central node regularly collects BIM data from various data sources; S22, data preprocessing: preprocess the collected BIM data, including data cleaning, format conversion, and compression; S23, data packaging and hash calculation: the pre-processed BIM data is packaged into data blocks according to certain rules, each data block contains multiple BIM data items, and the hash value of the entire data block is calculated, and the hash value is used to verify the integrity and uniqueness of the data block; S24, block generation: combine the data block, hash value, timestamp, and hash value information of the previous block into a new block, and attach a signature to ensure the legitimacy and immutability of the block; the newly generated block will be added to the end of the blockchain to form a chain storage structure; S3, chained storage and version control, including: S31. Blockchain synchronization: All nodes regularly synchronize the latest blockchain data from the central node to ensure that the blockchain data on all nodes remain consistent; S32. Version record: Whenever BIM data changes, the change record is added to the blockchain as a new BIM data item and a new block is generated. The generation of the new block will trigger the version control process to ensure that the version information of the BIM data is accurately recorded. S33, Historical tracing: tracing the historical versions of BIM data by querying the blockchain; S4. Smart contract deployment and execution, including: S41. Smart contract writing: Write smart contract code according to the requirements of BIM data version control; the smart contract will include version control logic, permission control logic, and trigger conditions; S42. Smart contract deployment: deploy the written smart contract to the blockchain network; S43. Trigger condition setting: setting trigger conditions for smart contracts; S44. Smart contract execution: When the triggering conditions are met, the smart contract will be automatically executed; S5. Copyright tracking and protection, including: S51, Identification embedding: When publishing a BIM model, the right holder embeds a specific digital code as an identifier into the components of the BIM model; S52. Copyright information recording: before the BIM data is uploaded to the blockchain network, the copyright information is recorded separately; S53. Copyright verification: When BIM data is accessed or used, the blockchain network will automatically perform the copyright verification process; S54. Infringement tracking: Every data transaction is accurately recorded, so the copyright owner can clearly see when, where, and by whom the BIM data is accessed or modified; S6. User rights management, including: S61. Role definition: In the BIM data version control and tracking system, different user roles need to be defined, including copyright owners, data managers, designers, and construction personnel; each role has different permissions and responsibilities to ensure the security and effectiveness of BIM data; S62. Permission allocation: According to different user roles, corresponding permissions are allocated to them; permission allocation follows the principle of least privilege, that is, only the minimum set of permissions required for users to complete their work is granted; S63, authority verification: When a user accesses BIM data, the user's authority is verified; by comparing the authority information stored on the blockchain with the user's identity information, it is determined whether the user has the right to access the BIM data; if the verification fails, the user's access request will be rejected, and the corresponding log information will be recorded for subsequent auditing; S7. User rights management, including: S71. Data encryption: Encryption technology is used to encrypt data, including the use of symmetric encryption algorithms to encrypt and decrypt data, and the use of asymmetric encryption algorithms to manage and distribute keys; S72. Access control: Ensure that only authorized users can access BIM data by assigning different permissions to different user roles and using authentication and access logging; S73. Privacy protection: Data involving user privacy is protected by using data desensitization and anonymization; S8. System maintenance and optimization, including: S81. System monitoring: Establish a system monitoring mechanism to monitor the operation status, data transaction status, and user behavior of the blockchain network in real time; timely discover potential security risks and performance bottlenecks through monitoring, and provide strong guarantees for the stable operation of the system; S82. Performance optimization: Improve the transaction processing capability and response speed of the blockchain network by optimizing the consensus algorithm, increasing the block capacity, and introducing a cache mechanism; S83. Upgrade and iteration: Continuously improve the system's functionality and performance by regularly releasing new versions, fixing known vulnerabilities, and introducing new features.

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