Block chain-based mechanical and electrical product carbon footprint credible evidence storage and cross-chain traceability method

Abstract

The invention discloses an electromechanical product carbon footprint credible evidence storage and cross-chain traceability method based on a block chain, and belongs to the field of block chain technology application. Comprising the steps that a mechanical and electrical product carbon footprint layered traceability information model is constructed, all enterprises complete carbon footprint data collection and standardized traceability information unit generation based on the model, and after private cloud security storage, credible evidence storage is achieved based on an on-chain and off-chain cooperation mode; multi-chain carbon footprint evidence information verification and cross-chain integration are completed based on a relay chain cross-chain architecture, a unique traceability identifier of a related product is linked, and traceability information integrity verification is realized by using digital fingerprints. According to the invention, a standardized carbon footprint traceability information system can be constructed, and carbon data standard acquisition, standardized traceability information unit generation and on-chain and off-chain credible evidence storage are realized; multi-chain carbon footprint evidence information verification and cross-chain integration are completed based on a relay chain architecture, and the block chain island problem is solved; in addition, fine-grained permission control is supported, and differential sharing of the carbon data under privacy protection is realized.

Description

TECHNICAL FIELD

[0001] The application belongs to the application field of blockchain technology, and relates to a mechanical and electrical product carbon footprint traceability technology, in particular to a mechanical and electrical product carbon footprint credible storage and cross-chain traceability method based on a blockchain. BACKGROUND

[0002] Product Carbon Footprint (PCF) is the total amount of greenhouse gas emissions directly and indirectly generated in the entire life cycle of a product, and is an important indicator for measuring the green and low-carbon level of production enterprises and products. Mechanical and electrical product carbon footprint traceability can support the reproduction of product carbon footprint accounting results by recording the flow track of data and accurately associating the sources and calculation basis of carbon emission data at each link. Realizing mechanical and electrical product carbon footprint traceability can provide accurate data support for enterprises, help enterprises develop emission reduction strategies, optimize product production processes, and other green and low-carbon transformation measures, and also help enterprises identify the precise positioning and responsibility definition of high-carbon links.

[0003] Mechanical and electrical product carbon footprint traceability has the characteristics of various formats, scattered sources, and high privacy: firstly, the carbon data collection methods and record formats of different subjects are different, and the standardization degree and credibility are low; secondly, the data comes from raw material suppliers, component manufacturers, whole machine manufacturers, logistics providers and other independent subjects, and the sources are scattered and the cross-organizational characteristics are significant, and the whole chain needs to be connected relying on the supply chain relationship; thirdly, carbon data is often associated with sensitive business information such as enterprise production processes, bill of materials, energy consumption standards, and privacy protection needs are prominent. Traditional traceability systems relying on centralized database management have many problems, such as serious centralization of traceability systems, data tampering, lack of openness and transparency in data access, and data loss. Blockchain is very suitable for solving the problems of centralization, data monitoring loss, data tracking, and lack of trust in traditional traceability systems due to its characteristics of decentralization, traceability, and tamper resistance, and has become the mainstream solution in the current traceability field. Current research can be divided into the following two aspects:

[0004] 1. Product carbon footprint traceability based on blockchain: researches often focus on the accurate collection and credible accounting of carbon footprint data, with the product life cycle assessment (LCA) as the core framework. In view of the complexity and large volume of carbon footprint data, researches often combine modular unit splitting, type filtering and other methods to improve traceability efficiency and adaptability to differentiated needs. However, the existing traceability information model, cross-chain integration scheme and privacy protection strategy lack targeted design for the core characteristics of mechanical and electrical products, such as multi-component assembly, multi-production link coordination and complex carbon footprint data dimensions, and cannot support accurate traceability and credible management of mechanical and electrical product life cycle carbon footprint.

[0005] 2. Blockchain-based supply chain information traceability research: Blockchain technology has been widely applied to supply chain information traceability in food, textiles, agricultural products and other fields, forming a series of technical solutions and accumulating practical experience. A large number of studies use the collaborative mode of "on-chain verification + off-chain storage" to reduce the storage pressure of the blockchain and improve the scalability of the system. In terms of cross-chain integration, existing research has achieved heterogeneous multi-chain collaborative traceability by building a double / multi-chain architecture, designing a multi-level index structure, and using notarization group cross-chain technology, taking into account the flexibility and security of data sharing. In addition, mainstream research has achieved privacy information protection and fine-grained access control by integrating zero-knowledge proof, attribute encryption and other technologies while ensuring traceability functions.

[0006] In summary, the present application proposes a method for the trusted storage and cross-chain traceability of the carbon footprint of electromechanical products based on blockchain, which can fill the gaps in existing technologies and has urgent practical needs and practical value. SUMMARY

[0007] The technical scheme adopted by the present application is a method for the trusted storage and cross-chain traceability of the carbon footprint of electromechanical products based on blockchain, comprising the following steps:

[0008] Step 1: Build a hierarchical traceability information model for the carbon footprint of electromechanical products. Each enterprise completes carbon footprint data collection, standardized traceability information unit generation based on this model, and after secure storage in a private cloud, achieves trusted storage based on the on-chain and off-chain collaborative mode.

[0009] Step 2: Based on the cross-chain architecture of the relay chain, combined with ECDSA digital signature and RSA accumulator, complete multi-chain carbon footprint storage information verification and cross-chain integration, and associate the product unique traceability identifier on-chain.

[0010] Step 3: Based on RSA accumulator and ABAC technology, achieve fast identity authentication and fine-grained access control of supply chain members, and use digital fingerprints to achieve traceability information integrity verification.

[0011] Further, the specific method in step 1 includes:

[0012] Step 1.1: According to the relevant standards for product carbon footprint accounting and the industry practice of life cycle assessment of electromechanical products, taking into account the hierarchical structure of electromechanical product BOM and the multi-agent collaboration characteristics of the supply chain, build a hierarchical traceability information model for the carbon footprint of electromechanical products according to the hierarchical division method of "product structure-supply chain information-enterprise operation-carbon emission activities-inventory analysis-carbon footprint". This information model provides a unified and standardized basis for data collection and structured storage for each link enterprise, and clearly defines the core data dimensions and hierarchical correlation logic of electromechanical product carbon footprint traceability, providing a structured data foundation for the reproduction of carbon footprint accounting process, responsibility tracing and multi-role differentiated traceability.

[0013] Step 1.2: Each enterprise first leverages its existing IT infrastructure to acquire supporting data related to its carbon footprint. This data can originate from various information systems such as Manufacturing Execution Systems (MES) and Enterprise Resource Planning (ERP), and also supports IoT sensors, manual data entry, and requests from upstream enterprises. After completing the carbon data collection, carbon footprint calculations are performed on a local server to ultimately obtain the carbon footprint value for all carbon emission activities at that node, laying the foundation for subsequent data processing.

[0014] Step 1.3: All traceability information involved in the carbon footprint collection and accounting phases is categorized, organized, and structured into JSON format strings according to the requirements of the hierarchical traceability information model. Simultaneously, a globally unique ID is generated for each traceability information unit based on the UUID algorithm for subsequent storage and retrieval. Ultimately, this data is categorized and stored in a specific, secure directory structure on a local private cloud, completing the physical disk storage of the traceability data at the generation node, forming a complete, efficient, and quickly searchable local traceability archive within the enterprise.

[0015] Step 1.4: Following the on-chain and off-chain collaborative storage mechanism, each supply chain enterprise initiates a blockchain transaction. First, digital fingerprints are generated for each level of data in the traceability information unit based on SHA-256. Then, carbon footprint ID, off-chain storage address, enterprise information, and supply chain business information are integrated. The data for this notarization is digitally signed using the enterprise's private key based on ECDSA (Elliptic Curve Digital Signature Algorithm). Finally, the above parameters are packaged together with the enterprise's public key and submitted to the blockchain notarization smart contract, completing the on-chain notarization of core data.

[0016] Step 1.5: Each member of the supply chain (raw material suppliers, storage and transportation companies, component manufacturers, product manufacturers, etc.) repeats the above process locally to complete the collection, calculation, structuring, and on-chain and off-chain collaborative evidence storage of their own carbon footprint data, ultimately forming a pattern of off-chain distributed storage of complete traceability data and on-chain distributed evidence storage of credible core information.

[0017] Furthermore, the specific methods in step 2 include:

[0018] Step 2.1: Build a cross-chain architecture based on the relay chain. The cross-chain alliance is jointly formed by the organizations of raw material enterprises, manufacturing enterprises, and logistics enterprises to maintain the relay chain. Each application chain deploys cross-chain gateways and smart contracts to complete registration and access.

[0019] Step 2.2: The final product manufacturer, acting as the initiating party, uses its business information (such as purchase orders, supplier information, and logistics orders) as a guide to identify all directly upstream enterprises involved in this step. Through a cross-chain architecture, it sequentially initiates cross-chain evidence data retrieval requests to these upstream enterprises. Upon receiving this request, the upstream enterprise recursively initiates integration upstream until the request reaches the original raw material supplier. Afterward, the requested data returns along the original path, undergoing integration processing at each hop.

[0020] Step 2.3: Integrate the smart contract based on the public key to perform validity verification on the digital signature field in the upstream enterprise's notarization, confirming the legality of the information source and the integrity of the notarized data, and preventing non-supply chain members from forging information and affecting the traceability results. If the verification passes, continue to the subsequent process; if the verification fails, record the error log and notify the upstream enterprise.

[0021] Step 2.4: Once the digital signature verification of the direct upstream enterprise passes, indicating that it is a legitimate participant in the supply chain, the supply chain member accumulator maintenance step is then executed. The accumulator state is updated using the accumulator update algorithm, and the upstream enterprise is added to the current product supply chain member accumulator to obtain the updated accumulator value.

[0022] Step 2.5: After the integration process is completed, a complete traceability chain is obtained, and the identity information of each enterprise is aggregated into the final RSA accumulator value. For batch-produced electromechanical products, a globally unique traceability identifier (TraceID) is generated as the identity index of the carbon footprint of the batch of products through a combination of "product category code + enterprise unique identifier + product model + production batch number + production date + check digit". This TraceID is packaged together with the above integration results and submitted to the blockchain for notarization as the starting point for subsequent traceability.

[0023] Furthermore, the specific methods in step 3 include:

[0024] Step 3.1: The traceability party (including supply chain enterprises, consumers, and regulatory authorities) submits the product's unique traceability identifier (TraceID) and its own identity information, and initiates a carbon footprint traceability request through the on-chain service interface.

[0025] Step 3.2: Verify the identity of the traceability party. For consumers, they can only see the carbon footprint exposed at the final product level and do not have the authority to trace specific components or transportation links. For regulatory authorities, they have traceability authority for all products by default and can skip this stage. For supply chain companies, they need to use the RSA member accumulator maintained during the cross-chain integration of product carbon footprints to achieve rapid verification of supply chain members.

[0026] Step 3.3: After identity verification is successful, the traceability smart contract parses the application chain to which the traceability data belongs based on the traceability link information stored on the chain, and generates a cross-chain traceability request. The request is encapsulated into a general cross-chain protocol format by the cross-chain gateway and submitted to the relay chain; after verifying the legality of the request and the status of the destination chain, the relay chain forwards the request to the cross-chain gateway of the corresponding destination chain through cross-chain routing.

[0027] Step 3.4: The traceability request reaches the destination chain. The destination chain enterprise, based on the Attribute Access Control (ABAC) model, pre-defines its permission policy and stores it on-chain. The contract obtains the traceability party's attribute set and the requested resource attributes, matches them with the ABAC policy stored on-chain, and determines the data hierarchy range that the traceability party can access. After the permission determination is passed, based on the off-chain storage address stored on-chain, the corresponding carbon footprint traceability information unit is retrieved from the destination chain enterprise's private cloud server, and the visible carbon footprint data within the permission range is returned.

[0028] Step 3.5: After receiving the returned traceability data, the traceability party regenerates a digital fingerprint for the corresponding level of data within its authorized scope using the SHA-256 algorithm, and compares it one by one with the fingerprint information stored on the blockchain. If the fingerprints match completely, it is determined that the data has not been tampered with during storage and transmission, and the data integrity is valid. The traceability result that has passed the verification is returned to the traceability party, completing the cross-chain traceability process.

[0029] Compared with existing technical solutions, the beneficial effects of the present invention are as follows:

[0030] 1. This invention proposes a six-layer carbon footprint traceability information model adapted to the characteristics of electromechanical products. Through layered design, it standardizes the data standards of the entire chain, supporting accurate carbon footprint traceability and reproduction.

[0031] 2. This invention adopts the "on-chain evidence storage and verification + off-chain distributed storage" model, combining digital fingerprint and digital signature technologies to ensure that the source of carbon data is verifiable and its integrity is verifiable, thus eliminating the risk of tampering.

[0032] 3. This invention utilizes the cross-chain architecture of the relay chain to solve the data silo problem caused by multiple chains storing evidence in parallel across various links of the supply chain, and constructs a carbon data circulation system that is fully integrated and traceable across chains.

[0033] 4. Based on accumulators and attribute access control, this invention achieves efficient verification of supply chain member identities and fine-grained access control of carbon data, taking into account both cross-chain traceability efficiency and enterprise privacy protection needs, and provides secure and controllable technical support for trusted sharing and differentiated access of carbon data in complex supply chain scenarios. Attached Figure Description

[0034] Figure 1 This is a flowchart of the method of the present invention.

[0035] Figure 2 This is a schematic diagram of the method of the present invention.

[0036] Figure 3 This is a diagram of the method architecture of the present invention.

[0037] Figure 4 This is a model diagram of the carbon footprint traceability information for electromechanical products according to the present invention.

[0038] Figure 5 This is a diagram of the on-chain evidence storage information model of the present invention.

[0039] Figure 6 This is a diagram of the on-chain and off-chain collaborative storage architecture of the present invention.

[0040] Figure 7 This is a diagram of the cross-chain architecture based on a relay chain according to the present invention.

[0041] Figure 8 This is a cross-chain request message flow diagram of the present invention.

[0042] Figure 9 This is a timing diagram of the cross-chain integration process of the carbon footprint of electromechanical products according to the present invention.

[0043] Figure 10 This is the ABAC model attribute design diagram for the present invention.

[0044] Figure 11 This is a flowchart illustrating the access control execution process of the present invention.

[0045] Figure 12 This is a timeline diagram of the cross-chain traceability process of the carbon footprint of electromechanical products according to the present invention. Detailed Implementation

[0046] To make the objectives, technical solutions, and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments and accompanying drawings, so as to enable those skilled in the art to understand the present invention.

[0047] Example

[0048] The following provides a detailed explanation of the blockchain-based method for trusted storage and cross-chain traceability of carbon footprints for electromechanical products. The method flow is as follows: Figure 1 As shown, the method model is as follows Figure 2 As shown, the method architecture is as follows Figure 3 As shown.

[0049] Step 1: Based on relevant standards for product carbon footprint accounting and industry practices for life cycle assessment of electromechanical products, and taking into account the hierarchical structure of the BOM (Bill of Materials) and the multi-entity collaboration characteristics of the supply chain, a hierarchical traceability information model for the carbon footprint of electromechanical products is constructed. Each enterprise first collects carbon data through a data collection entity and performs carbon footprint accounting on its local server. Then, relying on the hierarchical traceability information model, supporting data, data acquisition methods, accounting processes, and accounting results are formatted into JSON string format carbon footprint traceability information units according to the prescribed hierarchical traceability information model. A unique distributed ID is generated for each traceability information unit using the UUID algorithm and stored together in a trusted private cloud. Finally, based on the above data, digital fingerprints and digital signatures are calculated, and combined with the unique carbon data identifier and core information such as enterprise business information, they are uploaded to the blockchain to complete the trusted storage of the carbon footprint on the blockchain. The specific content of the carbon footprint traceability information model for electromechanical products is as follows: Figure 4 As shown, the content of the on-chain evidence storage information model is as follows: Figure 5 As shown, the on-chain and off-chain collaborative storage architecture is as follows: Figure 6 As shown.

[0050] Step 2: Each application chain, while retaining its original business logic, deploys cross-chain gateways and cross-chain smart contracts, integrating them into the cross-chain architecture based on the relay chain. Carbon footprint integration is initiated by the final product enterprise, which, based on the actual business activities of the product supply chain (such as purchase orders, supplier information, logistics orders, etc.), identifies all upstream enterprises associated with this stage and initiates integration requests upstream along the supply chain. After receiving the returned evidence data, the requesting party first verifies the legality of the elliptic curve digital signature, then uses an RSA accumulator to accumulate the identities of legitimate supply chain members into a unique value. If the supply chain has hierarchical relationships, the above process will recursively repeat along the supply chain until there are no more upstream business records, proving that all evidence data has been verified and integrated. At this point, the recursive query and integration terminate. After integration, a unique product identifier is generated, associated with the integration information, and stored on the chain as the entry point for subsequent traceability. The cross-chain architecture based on the relay chain is as follows: Figure 7 As shown, the cross-chain request message flow is as follows: Figure 8 As shown, the timing diagram of this process is as follows: Figure 9 As shown.

[0051] Step 3: The traceability provider initiates a traceability request based on the product's unique traceability identifier. First, an RSA accumulator is used for efficient supply chain member authentication to ensure the current traceability provider has traceability for the product. Then, based on the constructed traceability link, a search is performed, and the current identity information is carried in to initiate the traceability request. The request is executed on the target chain via a relay link. ABAC-related access control policies are deployed on the target chain. The smart contract determines access permissions according to the preset policy, retrieves traceability information from the target private cloud server, and returns carbon data within the accessible range of this request. The traceability provider uses the SHA-256 algorithm to generate a new hash value for the returned traceability information and compares it with the digital fingerprint in the on-chain evidence storage information to verify the authenticity and integrity of the traceability information, ensuring it has not been tampered with during storage. The ABAC model attributes are designed as follows during this process: Figure 10 As shown, the access control execution flow is as follows: Figure 11 As shown, the timing diagram of this process is as follows: Figure 12 As shown.

[0052] Furthermore, in step 1, the explanation of the carbon footprint traceability information model for electromechanical products, the process of generating digital fingerprints using the SHA-256 algorithm, and the process of generating digital signatures using ECDSA are described below:

[0053] 1. The carbon footprint traceability information model for electromechanical products is explained as follows:

[0054] This invention divides the carbon footprint data model for electromechanical products into six layers. The product structure layer constructs a structure tree starting with the Bill of Materials (BOM), breaking down the product into independently traceable units. The supply chain information layer connects upstream and downstream enterprises through orders, providing a basis for carbon data integration and clarifying responsibility. The enterprise operation layer links dynamic business processes and relies on internal information systems. The carbon emission activity layer analyzes the input and output of carbon emission activities to construct a logical chain between production activities and carbon emissions. The inventory analysis layer records information such as data acquisition and processing methods to realize the transformation of carbon data from qualitative to quantitative. The carbon footprint layer summarizes carbon emission results, providing a basis for the scientific evaluation of carbon footprint accounting.

[0055] 2. The process of generating a digital fingerprint using the SHA-256 algorithm is as follows:

[0056] Assuming the data to be stored is This is generated using the KJ-256 hash algorithm. hash value : Based on the hierarchical nature of the carbon footprint traceability information model for electromechanical products, it is necessary to generate and store digital fingerprints for each layer of data.

[0057]

[0058] 3. The process of generating a digital signature using ECDSA includes the following steps:

[0059] Step 1: Key pair ( Generate. First, based on public parameters ( , exist Determine the elliptic curve , satisfy Let n be a prime number of order G, and let the private key SK satisfy... Randomly generated:

[0060]

[0061] The public key PK is calculated using dot multiplication, where G is a base point on the elliptic curve:

[0062]

[0063] Step 2: Using the private key For evidence storage information Sign up. First, calculate the hash value of the data. Randomly select an integer d. ,calculate :

[0064]

[0065] Will Convert to integer , If r is 0, recalculate d from scratch; otherwise, recalculate. :

[0066]

[0067] Finally obtained .

[0068] Furthermore, in step 2, the explanation of the cross-chain architecture based on the relay chain, the process of verifying digital signatures using ECDSA, and the process of maintaining the supply chain member accumulator using the RSA algorithm are described below:

[0069] 1. The cross-chain architecture based on the relay chain is explained as follows:

[0070] This invention proposes a relay-based cross-chain solution, tailored to the practical business scenario of carbon data traceability in the product supply chain. Enterprises at each stage of the supply chain join their corresponding application chains, each of which is an independent blockchain. In the relay chain architecture, organizations or institutions form a cross-chain alliance, jointly maintaining the relay chain. Through the relay's cross-chain mechanism, cross-chain interaction between multiple application chains is achieved. When expansion is needed, the electromechanical product supply chain can be further extended by connecting to new application chains. This network topology enables cross-chain sharing and interaction, supporting cross-industry and cross-organizational application chain data transfer.

[0071] The cross-chain system is the core of the entire cross-chain architecture, mainly composed of a relay chain and a cross-chain gateway. The overall architecture of the relay cross-chain system comprises three parts: the application chain, the relay chain, and the cross-chain gateway. The relay chain is the most crucial part of the entire cross-chain architecture, primarily used for digital identity management, application chain management, and trusted verification and reliable routing of cross-chain transactions. The cross-chain gateway, as the interface for application chains to enter the cross-chain system, is an intermediary module used to collect and propagate transactions within a multi-blockchain system. It bridges the application chain and the relay chain, enabling stateless message passing. The cross-chain gateway mainly includes functions such as event listening, transaction submission, transaction reception, transaction forwarding, and execution of transactions submitted to the destination chain.

[0072] 2. The process of verifying a digital signature using ECDSA is as follows:

[0073] Based on the on-chain notarized data (Data), digital signature (Signature(r,s), and public key (PK), the received data is first hashed using the same algorithm. Next, the signature inverse in the signature algorithm is calculated. :

[0074]

[0075] pass and calculate :

[0076]

[0077]

[0078]

[0079] Will Convert to integer , ,if and If the signature matches, the signature passes; otherwise, the verification is invalid.

[0080] 3. The process of maintaining the supply chain member accumulator using the RSA algorithm specifically includes the following steps:

[0081] Step 1: Initialization of the RSA accumulator algorithm. Initialization is performed by the enterprise initiating the integration, based on preset security parameters. Generate the initial value of the accumulator. Then N is calculated using two secret large prime numbers p and q. .

[0082] Step 2: Calculate a unique prime number mapping for the current supply chain member using a public, collision-free hash function:

[0083]

[0084] in The output for supply chain companies currently awaiting inclusion in the accumulator This is a prime number that represents the unique identity of the supply chain member corresponding to the enterprise.

[0085] Step 3: Assume the current product member set is If the members to be added to the accumulator , Updated to The updated accumulator value:

[0086]

[0087] Furthermore, in step 3, the following is a description of supply chain member authentication based on RSA accumulators, access control based on ABAC, and carbon data integrity verification based on digital fingerprints:

[0088] 1. The process of supply chain member authentication based on RSA accumulator is as follows:

[0089] Assuming the source tracing party itself is The total number of members in the supply chain is n. The traceability party first starts with a list of prime numbers of the members. After removing the source party itself, we obtain Then the prime numbers of the other members are multiplied together. For the current traceability party, generate supply chain member verification certificates. as follows:

[0090]

[0091] Proof of use by current smart contracts And the unique prime number of the current source. Generate an accumulator value and compare it with the latest publicly verified accumulator values ​​of supply chain members on the blockchain. The comparison is used to prove the relationship between supply chain members, as shown in the following formula:

[0092]

[0093] If they are equal, the authentication is successful, indicating that the current traceability party is a member of the product's supply chain and has traceability authority; if they are not equal, the traceability request is rejected directly.

[0094] 2. The process of access control based on ABAC specifically includes the following steps:

[0095] Step 1: In the preparation phase, manage attribute sets in each application chain, including attributes such as users, resources and environment. Generate relevant strategies based on attribute information and deploy them on the blockchain. The strategy management contract supports dynamic adjustment of the contract.

[0096] Step 2: During the policy execution phase, the access control contract obtains the subject and object attribute sets by calling the attribute management contract. The call parameters include the subject ID and object ID. The access control contract retrieves the subject and object attributes from the attribute management contract. The access control contract then calls the policy management contract, with the object attributes included as parameters, to query relevant policies. The policy management contract searches for relevant policies using key-value queries and returns the found policies to the access control contract. Based on the obtained subject attributes, object attributes, operation type, operation environment, policy sets, and result merging algorithm, the access control contract determines whether the subject has the right to perform operations on the object, thus determining that the access request satisfies the access policy. The access control contract returns the determination result and decides whether to return the data to the requesting subject based on the result.

[0097] 3. The process of verifying carbon data integrity based on digital fingerprints is as follows:

[0098] After obtaining the corresponding traceability information unit, the tracer can regenerate a digital fingerprint using the SHA-256 algorithm and compare it with the digital fingerprint stored on the blockchain to verify the integrity of the traceability information and ensure that the traceability information has not been tampered with during storage. This process is illustrated in the formula:

[0099]

[0100] The input parameter is the content of the obtained carbon footprint traceability information unit. Digital fingerprints stored on the blockchain, To reuse digital fingerprints generated by the SHA-256 algorithm, by comparison and If they are equal, the verification passes; otherwise, the returned data is incomplete.

Claims

1. A blockchain-based method for carbon footprint credible storage and cross-chain traceability of electromechanical products, characterized in that, Comprise the following steps: Step 1: build a layered traceability information model of carbon footprint of electromechanical products, and each enterprise completes carbon footprint data collection, standardized traceability information unit generation based on the model, and realizes trusted storage based on on-chain and off-chain collaboration mode after safe storage in private cloud; Step 2: based on the cross-chain architecture of relay chain, combined with ECDSA digital signature and RSA accumulator, complete multi-chain carbon footprint storage information verification and cross-chain integration, and associate product unique traceability identification on-chain; Step 3: based on RSA accumulator and ABAC technology, realize fast identity authentication and fine-grained access control of supply chain members, and realize traceability information integrity verification by using digital fingerprint.

2. The blockchain-based electromechanical product carbon footprint trusted storage and cross-chain traceability method according to claim 1, characterized in that, The specific implementation process in step 1 is as follows: First, according to the relevant standards of product carbon footprint accounting and the industry practice of life cycle assessment of electromechanical products, taking into account the hierarchical structure of electromechanical product BOM and the multi-agent collaboration characteristics of supply chain, a layered traceability information model of carbon footprint of electromechanical products is constructed according to the hierarchical division method of "product structure-supply chain information-enterprise operation-carbon emission activity-inventory analysis-carbon footprint"; the information model provides unified and standardized data collection and structured storage basis for each link enterprise, and clearly defines the core data dimension and hierarchical correlation logic of electromechanical product carbon footprint traceability, providing a structured data basis for the reproduction of carbon footprint accounting process, responsibility tracing and differentiated traceability of multiple roles; Second, each enterprise first obtains carbon footprint related support data based on existing information infrastructure, which can come from production execution system MES, enterprise resource planning system ERP and other information systems, and also supports Internet of Things sensors, manual input and upstream enterprise request channels; after completing carbon data collection, carbon footprint accounting is performed on the local server, and the carbon footprint value of all carbon emission activities at this node is finally obtained, laying the foundation for subsequent data processing; Third, all traceability information involved in the carbon footprint collection and accounting stage is classified, arranged and structured into JSON format strings according to the requirements of the layered traceability information model, and a globally unique ID is generated for each traceability information unit based on the UUID algorithm to facilitate subsequent storage and query; finally, these data will be stored in a specific, security-protected directory structure in the local private cloud, completing the physical landing of traceability data at the generation node and forming a complete, efficient and quickly retrievable local traceability archive library within the enterprise; Fourth, according to the on-chain and off-chain collaborative storage mechanism, each supply chain enterprise initiates a blockchain transaction; first, generate a digital fingerprint for each level of traceability information unit data based on SHA-256, then integrate carbon footprint ID, off-chain storage address, enterprise information, supply chain business information, use enterprise private key to digitally sign this storage data based on elliptic curve digital signature algorithm ECDSA; finally, package the above parameters and enterprise public key together, submit to the blockchain storage smart contract, and complete the on-chain storage of core data; Step 5: Each member of the supply chain repeats the above steps locally to collect, calculate, structure, and store the carbon footprint data, and finally forms a pattern of complete traceability data stored in a distributed manner off-chain and core information stored in a distributed manner on-chain.

3. The blockchain-based electromechanical product carbon footprint trustworthy storage and cross-chain traceability method of claim 1, wherein, The specific method in step 2 is as follows: Step 1: Build a cross-chain architecture based on the relay chain, which is composed of raw material enterprises, manufacturing enterprises, and logistics enterprises. The cross-chain alliance is formed by the organizations belonging to these enterprises, and the relay chain is maintained. Each application chain deploys a cross-chain gateway and a smart contract to complete registration and access. Step 2: The final product manufacturer, as the integration leader, determines all direct upstream enterprises associated with this step based on its business information. It initiates a cross-chain data storage request to each upstream enterprise through the cross-chain architecture. The upstream enterprise recursively initiates integration to the upstream until the request reaches the raw material supplier at the source. The request data then returns along the original path and is integrated at each hop. Step 3: The integration smart contract verifies the validity of the digital signature field in the upstream enterprise's storage based on the public key, confirming the legality of the information source and the integrity of the storage data. This prevents non-supply chain members from falsifying information and affecting the traceability results. If the verification is successful, the process continues; otherwise, an error log is recorded and the upstream enterprise is notified. Step 4: When the digital signature of the direct upstream enterprise is verified, it indicates that it is a legal participant in the supply chain. The supply chain member accumulator maintenance step is then executed. The accumulator state is updated using the accumulator update algorithm, and the upstream enterprise is added to the current product supply chain member accumulator, resulting in an updated accumulator value. Step 5: After the integration process is completed, the complete traceability link is obtained, and the identity information of each enterprise is aggregated into the final RSA accumulator value. For batch-produced mechanical and electrical products, a globally unique traceability identifier TraceID is generated as the identity index of the carbon footprint of this batch of products through the combination of product category code, enterprise unique identifier, product model, production batch number, production date, and check digit. This TraceID is packaged together with the integration results and submitted to the blockchain for storage as the starting point for subsequent traceability.

4. The blockchain-based electromechanical product carbon footprint trustworthy storage and cross-chain traceability method of claim 1, wherein, The specific method in step 3 is as follows: Step 1: The traceability party submits the product unique traceability identifier TraceID and its own identity information and initiates a carbon footprint traceability request through the on-chain service interface. Step 2: Verify the identity of the traceability party. For consumers, only the carbon footprint exposed at the final product layer can be seen, and they do not have the right to trace specific components or transportation links. For regulatory authorities, they have the right to trace all products and can skip this step. For supply chain enterprises, they need to use the RSA member accumulator maintained during the product carbon footprint cross-chain integration process to quickly verify the supply chain members. Step 3: After the identity verification, the traceability smart contract analyzes the application chain to which the traceability data belongs based on the traceability link information stored on-chain, and generates a cross-chain traceability request. The request is packaged into a general cross-chain protocol format by the cross-chain gateway and submitted to the relay chain. After verifying the request legitimacy and the destination chain state, the relay chain forwards the request to the cross-chain gateway of the corresponding destination chain through cross-chain routing; In the fourth step, the traceability request reaches the destination chain, and the destination chain enterprise defines the permission policy and completes the on-chain evidence based on the attribute-based access control (ABAC) model; The contract obtains the attribute set of the traceability party and the request resource attribute, matches the ABAC policy of the on-chain evidence, and determines the data level range that the traceability party can access; After the permission determination, the corresponding carbon footprint traceability information unit is obtained from the private cloud server of the destination chain enterprise according to the off-chain storage address of the on-chain evidence, and the visible carbon footprint data within the permission range is returned; In the fifth step, after receiving the returned traceability data, the traceability party regenerates the digital fingerprint of the corresponding level data within the permission range through the SHA-256 algorithm, and compares it with the fingerprint information on the chain one by one. If the fingerprints are completely consistent, it is determined that the data has not been tampered with in the storage and transmission process, and the data integrity is valid. The traceability result that passes the verification is returned to the traceability party, and the cross-chain traceability process is completed.

Images