Blockchain multi-element cross-chain supervision method, system and device and storage medium

Abstract

The application discloses a kind of blockchain multivariate cross-chain supervision method, system, device and storage medium, it is related to blockchain supervision technical field.Governance chain is constructed based on cross-account cross-platform associated adaptive supervision scheme.Through governance chain deployment digital identity management contract, global unique identifier is generated for physical identity subject, and the identifier and multiple account addresses on multiple business chains are established Many-to-many mapping relationship;Cross-platform identity association is realized using the governance chain to issue verifiable credentials;Cross-chain middleware layer listens to each business chain block event and transaction log, and real-time obtains supervision target data;With global identifier as primary key, the complete cross-chain behavior trajectory view of physical identity subject is aggregated and generated;Based on adaptive supervision strategy library, dynamically match rules and execute differentiated supervision disposal, and the disposal result is stored on chain and evidenced.The application realizes the identity penetration mapping and closed-loop adaptive supervision of multiple chains and multiple accounts, and improves the efficiency of blockchain ecological supervision.

Description

Technical Field

[0001] This invention belongs to the field of blockchain regulatory technology, specifically relating to a blockchain multi-chain regulatory method, system, device, and storage medium. Background Technology

[0002] The rapid development of blockchain technology has fueled the booming growth of multi-chain ecosystems, with various public, consortium, and private chains finding widespread application in finance, supply chains, government affairs, and many other fields. However, with the increasing demand for cross-chain interaction and the continuous expansion of blockchain application scenarios, effectively regulating cross-chain transactions and diverse digital identities has become a key challenge in blockchain ecosystem security governance. In current blockchain networks, the same user can independently generate multiple anonymous or pseudonymous accounts on different business chains. The lack of a unified digital identity identification system and cross-chain identity association mechanism between chains makes it difficult to track and reconstruct the complete behavioral trajectory of a single physical identity entity across multiple blockchain platforms. This fragmented and anonymized nature of digital identities, while providing privacy protection for users, also provides opportunities for criminals to exploit multiple chains and accounts to commit money laundering, illegal fundraising, fraud, and other illegal activities.

[0003] Regarding the issue of cross-chain regulation in blockchain, some solutions have been proposed in existing technologies. For example, some solutions construct a regulatory architecture that includes a business system, a business chain, and a regulatory chain system. The regulatory chain listens to smart contract events on the business chain to obtain business data and perform cross-chain verification. Other solutions use homomorphic encryption and smart contract technology to build a cross-chain data interaction process to achieve cross-chain data regulation. Still others deploy a layer 2 network between the business chain and the regulatory chain to independently perform cross-chain verification, thereby reducing the processing burden on the regulatory chain. In addition, in terms of identity management, existing research has proposed a cross-chain identity authentication framework based on a relay chain mechanism, as well as a method for unified management of identity permissions in a hierarchical multi-chain network based on cross-chain identity and information mutual recognition mechanisms. However, most of the above-mentioned existing solutions focus on single-dimensional regulatory data collection or cross-chain identity authentication in specific scenarios, and have not yet formed a comprehensive cross-chain regulatory solution covering multiple business chains and multiple account systems. In particular, they lack the ability to uniformly manage and cross-platform associate the diverse digital identities of the same physical identity subject on different blockchain platforms.

[0004] In terms of digital identity management, current blockchain ecosystems operate independently in implementing decentralized identities. The diversity of DID methods, parsing mechanisms, and credential formats across different chains has become a major obstacle to interoperability, making it difficult to reuse digital identities across platforms. The most prominent challenge in regulatory practice lies in achieving a transparent mapping between on-chain and off-chain physical identities; otherwise, it leads to a predicament where accountability is impossible. Existing technologies cannot effectively solve the problem of reliable association and mapping between physical and online identities, nor can they effectively track, aggregate, and adaptively analyze the complete behavioral trajectory of the same physical identity subject using multiple account addresses across multiple business chain platforms. Therefore, there is an urgent need to construct a cross-account, cross-platform, adaptive regulatory method based on a governance chain to uniformly manage the diverse digital identities in the blockchain ecosystem, establish a reliable mapping between physical and online identities, and on this basis, achieve aggregated analysis and adaptive regulatory handling of cross-chain regulatory data, thereby improving the regulatory efficiency and security level of the blockchain ecosystem. Summary of the Invention

[0005] This invention addresses the shortcomings of existing technologies by providing a method, system, device, and storage medium for multi-chain supervision of blockchain.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0007] A multi-chain regulatory approach for blockchain includes the following steps: Construct a multi-dimensional cross-chain regulatory architecture, which includes a governance chain, several business chains, and a cross-chain middleware layer; Based on the digital identity management contract of the governance chain, a global digital identity identifier for the physical identity subject is generated, a mapping relationship is established between the global digital identity identifier and multiple on-chain account addresses of the physical identity subject on various business chains, and an identity mapping table is formed based on the mapping relationship. Based on the identity mapping table, a cross-platform association credential between the physical identity subject and the network identity is constructed; In response to a cross-chain regulatory trigger event, the governance chain obtains regulatory target data on the target business chain through the cross-chain middleware layer, queries cross-platform associated credentials based on the regulatory target data, and retrieves the global digital identity identifier of the regulatory target data. The governance chain queries the identity mapping table based on the global digital identity identifier to obtain all cross-platform and cross-account identity mapping records associated with the regulatory target data, and performs cross-platform data aggregation on the regulatory target data based on all cross-platform and cross-account identity mapping records to generate a cross-chain regulatory view; The governance chain, based on the cross-chain regulatory view and combined with a preset adaptive regulatory strategy library, performs adaptive regulatory analysis on the cross-chain behavior of the physical identity entity, generates regulatory decision results, executes corresponding regulatory disposal operations, and stores the regulatory decision results and disposal records on the chain for evidence.

[0008] As one possible implementation, the digital identity management contract based on the governance chain generates a global digital identity identifier for the physical identity subject, including the following steps: The physical identity entity submits an identity registration request to the governance chain through a trusted identity authentication channel; The governance chain calls the identity verification logic in the digital identity management contract to verify the authenticity of the identity information in the identity registration request, and after the verification is passed, generates a unique decentralized identity identifier for the physical identity subject based on the distributed digital identity identifier specification as the global digital identity identifier. The digital identity management contract derives a corresponding public-private key pair for the global digital identity identifier based on an asymmetric cryptographic algorithm, sends the private key of the public-private key pair to the terminal device of the physical identity subject through a secure channel, and binds the public key of the public-private key pair to the global digital identity identifier and stores it in the identity registry of the governance chain.

[0009] As one possible implementation, establishing the mapping relationship between the global digital identity identifier and the physical identity subject's multiple on-chain account addresses on each business chain includes the following steps: When the physical identity subject creates or uses an on-chain account on any business chain, the business chain sends an account association request to the governance chain through the cross-chain middleware layer. The account association request includes the global digital identity identifier, the chain identifier of the business chain, and the account address on the business chain. The legitimacy of the account association request is verified according to the digital identity management contract of the governance chain; If valid, the digital identity management contract creates or updates a mapping record in the identity mapping table, associates and stores the global digital identity identifier, the chain identifier of the business chain, and the account address triplet on the business chain, and records the mapping establishment timestamp, mapping status, and mapping validity period; the identity mapping table supports searching by global digital identity identifier to obtain a list of all cross-platform account addresses associated with the physical identity subject, and performing reverse searching by business chain identifier and account address to obtain the corresponding global digital identity identifier.

[0010] As one possible implementation, constructing a cross-platform association credential between a physical identity subject and a network identity based on the identity mapping table includes the following steps: The governance chain calls the verifiable credential generation service based on the mapping record in the identity mapping table, uses the global digital identity identifier as the credential holder identifier and the chain identifier of the governance chain itself as the credential issuer identifier, and constructs a declaration subject containing the global digital identity identifier, the target business chain identifier and the target account address. The governance chain uses its regulatory private key to digitally sign the claim subject, generate the verifiable claim, and encapsulate the verifiable claim and the claim subject into a complete verifiable credential. The governance chain distributes the verifiable credentials to the target business chain through the cross-chain middleware layer. When verifying the verifiable credentials, the target business chain first queries the governance chain for the latest status of the credentials through the cross-chain middleware layer to confirm that they have not been revoked. Then, it uses the pre-stored governance chain public key to verify the signature of the credentials. After the signature verification is successful, it extracts the account address in the claim subject and compares it with the current operating account address. If the comparison is consistent, it confirms that the physical identity subject has legitimate control over the account address.

[0011] As one possible implementation, in response to a cross-chain regulatory triggering event, the governance chain obtains regulatory target data from the target business chain through the cross-chain middleware layer, including the following steps: The cross-chain middleware layer configures a dedicated block listener for each business chain. The block listener connects to the network node of the business chain through the node application programming interface or light client protocol of the business chain and continuously listens for new block generation events of the business chain. In response to the detected new block generation event, the block listener parses the transaction list from the new block and extracts transaction data, smart contract call records and account status change information from the transaction list as the regulatory target data. At the same time, the regulatory target data is standardized in format and then reported to the governance chain through the cross-chain message protocol. The cross-chain middleware layer is also configured with a transaction log event listener, which is used to listen to event logs issued by smart contracts on each business chain that conform to the preset event signature specifications. When a target event log is detected, the transaction data and contract state change data associated with the event log are reported to the governance chain as supplementary regulatory target data.

[0012] As one possible implementation, the step of performing cross-platform data aggregation on the regulatory target data based on all cross-platform and cross-account identity mapping records to generate a cross-chain regulatory view includes the following steps: The governance chain uses the global digital identity identifier as the query key to retrieve all mapping records associated with the physical identity subject in the identity mapping table. Each mapping record contains a business chain identifier and its corresponding account address. The governance chain sends cross-chain data query requests to the corresponding business chain based on the retrieved business chain identifier and account address combination, in order to obtain historical transaction records, smart contract interaction records and account status change history related to the account address on each business chain. The governance chain uses the global digital identity identifier as the associated primary key to sort and semantically fuse the historical transaction records, smart contract interaction records, and account status change history from different business chains according to timestamps, generating a cross-chain regulatory view of the complete behavioral trajectory across multiple business chain platforms centered on the physical identity subject.

[0013] As one possible implementation, the governance chain, based on the cross-chain regulatory view and combined with a pre-set adaptive regulatory strategy library, performs adaptive regulatory analysis on the cross-chain behavior of the physical identity entity, generates regulatory decision results, and executes corresponding regulatory actions, specifically including the following steps: The governance chain extracts the behavioral feature vector of the physical identity subject from the cross-chain regulatory view; A pre-defined adaptive regulatory strategy library is provided, which contains several regulatory rules. Each regulatory rule defines triggering conditions, regulatory actions, and handling measures. The governance chain performs matching calculations between the behavioral feature vector and the triggering conditions of each regulatory rule in the adaptive regulatory strategy library, calculates the matching degree between the behavioral feature vector and the triggering conditions of each regulatory rule, and selects the regulatory rule with the highest matching degree as the target regulatory rule. The governance chain performs corresponding regulatory analysis operations on the cross-chain regulatory view according to the regulatory actions defined in the target regulatory rules, and executes the disposal measures defined in the target regulatory rules based on the analysis results.

[0014] As one possible implementation, it also includes: The governance chain synchronizes the regulatory decision results and disposal records to the relevant business chains through the cross-chain middleware layer, and stores the evidence on the governance chain. The synchronization operation adopts an eventual consistency distributed transaction mechanism. After completing the regulatory action, the governance chain generates a regulatory action record. The regulatory action record includes the action type, action object, action time and action basis. The regulatory action record is packaged into a cross-chain message and sent to each relevant business chain through the cross-chain middleware layer. After receiving the cross-chain message, each relevant business chain performs the corresponding local state change operation and returns a confirmation receipt to the governance chain. Once the governance chain has collected all confirmation receipts or reached the legally required number of confirmations within a preset timeout period, it writes the hash value of the regulatory action record into the evidence storage block of the governance chain.

[0015] A blockchain-based multi-chain regulatory system includes: The cross-chain regulatory module constructs a multi-dimensional cross-chain regulatory architecture, which includes a governance chain, several business chains, and a cross-chain middleware layer. The identity mapping module generates a global digital identity identifier for the physical identity subject based on the digital identity management contract of the governance chain, establishes a mapping relationship between the global digital identity identifier and multiple on-chain account addresses of the physical identity subject on various business chains, and forms an identity mapping table based on the mapping relationship. The credential construction module constructs cross-platform association credentials between physical identity subjects and network identities based on the identity mapping table; The identity module responds to cross-chain regulatory trigger events. The governance chain obtains regulatory target data on the target business chain through the cross-chain middleware layer, queries cross-platform associated credentials based on the regulatory target data, and retrieves the global digital identity identifier of the regulatory target data. The cross-chain regulatory module involves the governance chain querying the identity mapping table based on the global digital identity identifier to obtain all cross-platform and cross-account identity mapping records associated with the regulatory target data, and then performing cross-platform data aggregation on the regulatory target data based on all cross-platform and cross-account identity mapping records to generate a cross-chain regulatory view. The regulatory analysis module, based on the cross-chain regulatory view and combined with a preset adaptive regulatory strategy library, performs adaptive regulatory analysis on the cross-chain behavior of the physical identity entity, generates regulatory decision results, executes corresponding regulatory disposal operations, and stores the regulatory decision results and disposal records on the blockchain for evidence.

[0016] The present invention also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the method described in any one of the following ways: Construct a multi-dimensional cross-chain regulatory architecture, which includes a governance chain, several business chains, and a cross-chain middleware layer; Based on the digital identity management contract of the governance chain, a global digital identity identifier for the physical identity subject is generated, a mapping relationship is established between the global digital identity identifier and multiple on-chain account addresses of the physical identity subject on various business chains, and an identity mapping table is formed based on the mapping relationship. Based on the identity mapping table, a cross-platform association credential between the physical identity subject and the network identity is constructed; In response to a cross-chain regulatory trigger event, the governance chain obtains regulatory target data on the target business chain through the cross-chain middleware layer, queries cross-platform associated credentials based on the regulatory target data, and retrieves the global digital identity identifier of the regulatory target data. The governance chain queries the identity mapping table based on the global digital identity identifier to obtain all cross-platform and cross-account identity mapping records associated with the regulatory target data, and performs cross-platform data aggregation on the regulatory target data based on all cross-platform and cross-account identity mapping records to generate a cross-chain regulatory view; The governance chain, based on the cross-chain regulatory view and combined with a preset adaptive regulatory strategy library, performs adaptive regulatory analysis on the cross-chain behavior of the physical identity entity, generates regulatory decision results, executes corresponding regulatory disposal operations, and stores the regulatory decision results and disposal records on the chain for evidence.

[0017] A blockchain multi-chain supervision device includes a memory, a processor, and a computer program stored in the memory and running on the processor. When the processor executes the computer program, it implements the method described in any one of the following ways: Construct a multi-dimensional cross-chain regulatory architecture, which includes a governance chain, several business chains, and a cross-chain middleware layer; Based on the digital identity management contract of the governance chain, a global digital identity identifier for the physical identity subject is generated, a mapping relationship is established between the global digital identity identifier and multiple on-chain account addresses of the physical identity subject on various business chains, and an identity mapping table is formed based on the mapping relationship. Based on the identity mapping table, a cross-platform association credential between the physical identity subject and the network identity is constructed; In response to a cross-chain regulatory trigger event, the governance chain obtains regulatory target data on the target business chain through the cross-chain middleware layer, queries cross-platform associated credentials based on the regulatory target data, and retrieves the global digital identity identifier of the regulatory target data. The governance chain queries the identity mapping table based on the global digital identity identifier to obtain all cross-platform and cross-account identity mapping records associated with the regulatory target data, and performs cross-platform data aggregation on the regulatory target data based on all cross-platform and cross-account identity mapping records to generate a cross-chain regulatory view; The governance chain, based on the cross-chain regulatory view and combined with a preset adaptive regulatory strategy library, performs adaptive regulatory analysis on the cross-chain behavior of the physical identity entity, generates regulatory decision results, executes corresponding regulatory disposal operations, and stores the regulatory decision results and disposal records on the chain for evidence.

[0018] This invention, by adopting the above technical solutions, has significant technical effects: Compared to existing technologies, this invention constructs a unified digital identity management framework centered on a governance chain, achieving multi-faceted supervision of blockchain. In existing technologies, the digital identity systems of various blockchain ecosystems are independent, with significant differences in decentralized identity identifier methods, resolution mechanisms, and credential formats between different chains. This makes cross-chain identity mutual recognition impossible, and it also fails to effectively associate anonymous on-chain accounts with off-chain physical identity entities. This invention deploys a unified digital identity management contract on the governance chain, generating a globally unique decentralized identity identifier for each physical identity entity. It establishes a many-to-many dynamic mapping relationship between this identifier and any number of account addresses of the same physical identity entity across multiple business chains through an identity mapping table. Simultaneously, it uses verifiable credentials issued by the governance chain as cross-platform identity association credentials, achieving a transparent and trusted mapping from physical identity to network identity.

[0019] Furthermore, this invention proposes a method for cross-chain regulatory data acquisition and aggregation analysis. Existing technologies often employ single-dimensional data collection methods or only conduct independent regulation of specific business chains, lacking the ability to comprehensively track the behavior of the same entity across multiple business chain platforms and multiple account addresses. This invention configures independent block listeners and transaction log event listeners for each business chain through a cross-chain middleware layer, acquiring multi-chain transaction data, smart contract call records, and account status change information in real time. It innovatively uses a global digital identity identifier as the association primary key, performing time-axis sorting and semantic fusion of dispersed regulatory data from heterogeneous blockchains to generate a cross-chain regulatory view centered on the physical identity entity. This achieves, for the first time, the complete behavioral trajectory reconstruction and tracking across multiple chains and accounts, effectively solving the regulatory blind spot problem caused by the fragmentation of digital identities in the blockchain ecosystem.

[0020] Furthermore, this invention constructs an adaptive regulatory strategy library and a dynamic rule matching mechanism. Existing regulatory rules are mostly pre-configured and lack the ability to dynamically perceive and adaptively respond to cross-chain behavioral characteristics. This invention extracts multi-dimensional behavioral feature vectors from the cross-chain regulatory view, calculates the matching degree with the triggering conditions of each rule in the strategy library, dynamically selects the optimal regulatory rule, and executes differentiated regulatory actions. Simultaneously, the results are recorded on the blockchain and synchronized to each business chain, forming a closed-loop regulatory process. This adaptive regulatory decision-making mechanism based on multi-chain behavioral characteristics not only improves the accuracy and flexibility of regulation but also transforms passive post-audit regulation into proactive real-time dynamic regulation. Attached Figure Description

[0021] Figure 1 This is a schematic flowchart of the method of the present invention; Figure 2 This is a system architecture diagram of the present invention. Detailed Implementation

[0022] To clearly illustrate the present invention and make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings, so that those skilled in the art can implement the invention based on the description. The technology of the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0023] Example 1: A multi-chain regulatory approach for blockchain, such as Figure 1 As shown, it includes the following steps: S100. Construct a multi-dimensional cross-chain regulatory architecture, which includes a governance chain, several business chains, and a cross-chain middleware layer. S200. Based on the digital identity management contract of the governance chain, generate a global digital identity identifier for the physical identity subject, establish a mapping relationship between the global digital identity identifier and multiple on-chain account addresses of the physical identity subject on various business chains, and form an identity mapping table based on the mapping relationship. S300. Based on the identity mapping table, construct a cross-platform association credential between the physical identity subject and the network identity; S400. In response to a cross-chain regulatory trigger event, the governance chain obtains regulatory target data on the target business chain through the cross-chain middleware layer, queries cross-platform associated credentials based on the regulatory target data, and retrieves the global digital identity identifier of the regulatory target data. S500. The governance chain queries the identity mapping table based on the global digital identity identifier to obtain all cross-platform and cross-account identity mapping records associated with the regulatory target data, and performs cross-platform data aggregation on the regulatory target data based on all cross-platform and cross-account identity mapping records to generate a cross-chain regulatory view. S600. The governance chain, based on the cross-chain regulatory view and combined with a preset adaptive regulatory strategy library, performs adaptive regulatory analysis on the cross-chain behavior of the physical identity subject, generates regulatory decision results and executes corresponding regulatory disposal operations, and stores the regulatory decision results and disposal records on the chain for evidence.

[0024] S100. Construct a multi-faceted cross-chain regulatory architecture, which includes a governance chain, several business chains, and a cross-chain middleware layer, specifically: In this embodiment of the invention, a multi-faceted cross-chain regulatory architecture based on a governance chain is constructed. The regulatory architecture includes a governance chain, several business chains, and a cross-chain middleware layer. The governance chain serves as the regulatory anchor chain, used to uniformly manage the chain identifier, chain type, consensus mechanism parameters, and cross-chain communication protocol configuration information of each business chain. The business chains include any one or more combinations of public chains, consortium chains, and private chains. The cross-chain middleware layer is deployed between each business chain and the governance chain, used to realize protocol conversion, data format adaptation, and message routing and forwarding between heterogeneous blockchain networks. S200. Based on the digital identity management contract of the governance chain, generate a global digital identity identifier for the physical identity subject, establish a mapping relationship between the global digital identity identifier and multiple on-chain account addresses of the physical identity subject on various business chains, and form an identity mapping table based on the mapping relationship. In this embodiment of the invention, considering the diverse nature of digital identities in the blockchain ecosystem, a unified digital identity management contract is constructed on the governance chain to generate a unique global digital identity identifier for each physical identity entity. A many-to-many mapping relationship is established between the global digital identity identifier and multiple on-chain account addresses of the physical identity entity on various business chains. The digital identity management contract is implemented based on a distributed digital identity standard, deriving a public-private key pair for each physical identity entity using an asymmetric cryptographic algorithm, and using the hash value of the public key as the global digital identity identifier. The many-to-many mapping relationship is stored in the identity mapping table of the governance chain. Each record in the identity mapping table includes at least the global digital identity identifier, business chain identifier, account address on that business chain, mapping establishment timestamp, and mapping status fields. In the above steps, a unified digital identity management contract is built on the governance chain to generate a unique global digital identity identifier for each physical identity entity, specifically including the following sub-steps: Sub-step S2001: The physical identity subject submits an identity registration request to the governance chain through a trusted identity authentication channel. The identity registration request includes at least one of the physical identity subject's biometric information, legal identity document information, and real-name authentication information. The trusted identity authentication channel includes any one or more combinations of a real-name authentication interface that interfaces with an authoritative identity authentication authority, a digital certificate authentication channel based on an authoritative public key infrastructure, and a remote identity verification channel based on a trusted execution environment. The biometric information includes at least one of fingerprint features, facial features, and iris features, which are hashed and processed into a feature template. Sub-step S2002: The governance chain calls the identity verification logic in the digital identity management contract to verify the authenticity of the identity information in the identity registration request. After the verification is passed, a unique decentralized identity identifier is generated for the physical identity subject based on the distributed digital identity identifier specification as the global digital identity identifier. The authenticity verification includes cross-comparison verification with an authoritative identity database, authentication of identity documents through optical character recognition technology, and verification of the real-time nature of biometric information based on liveness detection technology. The decentralized identity identifier follows the DID specification, and its format includes a method identifier, a method-specific identifier string, and a checksum field. Sub-step S2003: The digital identity management contract derives a corresponding public-private key pair for the global digital identity identifier based on an asymmetric cryptographic algorithm. The private key of the public-private key pair is sent to the terminal device of the physical identity subject via a secure channel. The public key of the public-private key pair is bound to the global digital identity identifier and stored in the identity registry of the governance chain. The secure channel includes at least one of the following: a network channel encrypted based on transport layer security protocols, an encrypted communication connection based on secure sockets, and a secure data transmission channel based on end-to-end encryption mechanisms. The identity registry stores the binding relationship between the global digital identity identifier and the public key in key-value pairs, and also stores registration time, registration channel, identity authentication level, and key status information.

[0025] In the above steps, establishing the many-to-many mapping relationship between the global digital identity identifier and the multiple on-chain account addresses of the physical identity subject on each business chain specifically includes the following sub-steps: Sub-step S2004: When the physical identity entity creates or uses an on-chain account on any business chain, the business chain sends an account association request to the governance chain through the cross-chain middleware layer. The account association request carries the global digital identity identifier, the chain identifier of the business chain, and the account address on the business chain. The creation of the on-chain account includes any one of the following scenarios: the physical identity entity generates an account address for the first time on the business chain, imports an existing account address on the business chain, or creates a contract account on the business chain through a smart contract. The account association request also includes ownership proof information of the physical identity entity for the account address. The ownership proof information includes a digital signature generated by signing a preset challenge value using the private key corresponding to the global digital identity identifier. Sub-step S2005: The digital identity management contract of the governance chain verifies the legality of the account association request. The verification includes verifying the validity of the digital signature in the account association request, verifying whether the global digital identity identifier has been registered in the identity registry, and verifying whether the chain identifier of the business chain belongs to the set of legitimate business chains managed by the governance chain. The validity verification of the digital signature is achieved by calling the public key stored in the identity registry to perform a signature verification operation on the digital signature. The set of legitimate business chains is maintained in the chain management contract of the governance chain. This set records the chain identifier, chain type, access status, and regulatory authorization level of the governance chain for each business chain. Sub-step S2006: After successful verification, the digital identity management contract creates or updates a mapping record in the identity mapping table, associating and storing the global digital identity identifier, the chain identifier of the business chain, and the triplet of the account address on the business chain. It also records the mapping establishment timestamp, mapping status, and mapping validity period, thereby achieving many-to-many mapping between multiple on-chain account addresses of the same physical identity entity across multiple business chains and the same global digital identity identifier. The mapping status includes valid, pending review, frozen, and expired states. The mapping validity period is dynamically adjusted according to regulatory policies. When a mapping record expires, the physical identity entity needs to re-verify the account association to extend the mapping relationship. The identity mapping table supports searching by the global digital identity identifier to obtain a list of all cross-platform account addresses associated with the physical identity entity, and performing reverse searches by business chain identifier and account address to obtain the corresponding global digital identity identifier.

[0026] S300. Based on the identity mapping table, construct a cross-platform association credential between the physical identity subject and the network identity; In this embodiment of the invention, a cross-platform association credential between physical identity and network identity is constructed based on the many-to-many mapping relationship. The association credential includes the global digital identity identifier, the target business chain identifier, the target account address, and a verifiable statement issued by the governance chain. The verifiable statement adopts the W3C verifiable credential data model format and includes issuer information, holder information, statement content, issuance time, and validity period. The governance chain digitally signs the verifiable statement with its private key so that each business chain can verify the authenticity and integrity of the association credential. The construction of the cross-platform association credential between physical identity and network identity specifically includes the following sub-steps: Sub-step S3001: The governance chain, based on the established mapping records in the identity mapping table, calls the verifiable credential generation service, using the global digital identity identifier as the credential holder identifier and the governance chain's own chain identifier as the credential issuer identifier, to construct a declaration body containing the global digital identity identifier, the target business chain identifier, and the target account address; the verifiable credential generation service, as a smart contract service or off-chain trusted service on the governance chain, provides credential generation, credential updating, and credential revocation functions to various business chains through a standardized application programming interface; the declaration body is serialized in JSON-LD format for cross-platform parsing and verification; Sub-step S3002: The governance chain uses its supervisory private key to digitally sign the claim subject, generating the verifiable claim, and encapsulates the verifiable claim and the claim subject into a complete verifiable credential. The verifiable credential also includes a credential identifier, issuance time, validity period, credential type, and credential status information. The credential identifier is a globally unique identifier, generated by the governance chain based on a universal unique identifier standard or a snowflake algorithm based on time series. The credential type identifies the credential as a cross-platform account-linked credential. The credential status information includes whether the credential is currently valid, whether it has been revoked, and the reason for revocation. Sub-step S3003: The governance chain distributes the verifiable credential to the target business chain through the cross-chain middleware layer. This allows the target business chain to verify the physical identity entity's operational permissions on the chain using the governance chain's public key, confirming the association between the physical identity entity and the target account address. When verifying the verifiable credential, the target business chain first queries the governance chain for the latest status of the credential through the cross-chain middleware layer to confirm it has not been revoked. Then, it verifies the credential signature using the pre-stored governance chain public key. If the verification is successful, the account address in the claim subject is extracted and compared with the current operating account address. If the comparison matches, the physical identity entity's legitimate control over the account address is confirmed.

[0027] S400. In response to a cross-chain regulatory trigger event, the governance chain obtains regulatory target data on the target business chain through the cross-chain middleware layer, queries cross-platform associated credentials based on the regulatory target data, and retrieves the global digital identity identifier of the regulatory target data. In this embodiment of the invention, in response to a cross-chain regulatory trigger event, the governance chain obtains regulatory target data from the target business chain through the cross-chain middleware layer. The regulatory target data includes transaction data, smart contract call records, and account status change information. The cross-chain regulatory trigger event includes at least one of the following: proactive regulatory requests from regulatory agencies, automatic triggering conditions met based on preset regulatory rules, and abnormal events reported by the business chain. The cross-chain middleware layer obtains the regulatory target data in real time by monitoring the block generation events and transaction log events of each business chain. The cross-chain middleware layer obtains the regulatory target data in real time by monitoring block generation events and transaction log events of each business chain, specifically including the following sub-steps: Sub-step S4001: The cross-chain middleware layer configures a dedicated block listener for each business chain. The block listener connects to the network node of the business chain through the node application programming interface or light client protocol of the business chain and continuously listens for new block generation events of the business chain. The light client protocol includes a simple payment verification protocol. The block listener realizes timely detection of new block generation events by maintaining the block header synchronization state of the business chain. When a new block is detected, the block listener records the block height, block hash and timestamp information of the block. Sub-step S4002: In response to the detected new block generation event, the block listener parses the transaction list from the new block and extracts transaction data, smart contract call records, and account status change information from the transaction list as the regulatory target data. Simultaneously, the regulatory target data undergoes format standardization processing and is reported to the governance chain via a cross-chain messaging protocol. The format standardization processing includes uniformly converting the heterogeneous data structures of different business chains into a standard data format defined by the governance chain. The standard data format includes the data source chain identifier, block height, transaction hash, transaction type, transaction participant identifier, transaction amount or data volume, timestamp, and hash digest of the original transaction data. The cross-chain messaging protocol is implemented based on a lightweight message queue protocol or a streaming protocol based on HTTP / 2. Sub-step S4003: The cross-chain middleware layer is also configured with a transaction log event listener, used to listen to event logs issued by smart contracts on each business chain that conform to a preset event signature specification. When a target event log is detected, the transaction data and contract state change data associated with the event log are reported to the governance chain as supplementary regulatory target data. The preset event signature specification defines a standard format for event name, event parameter type, and event parameter order. The target event log includes smart contract events that conform to the preset event signature specification. The transaction log event listener selectively listens to specific events by subscribing to the event log filtering interface of each business chain, thereby reducing the transmission overhead of irrelevant data.

[0028] S500. The governance chain queries the identity mapping table based on the global digital identity identifier to obtain all cross-platform and cross-account identity mapping records associated with the regulatory target data, and performs cross-platform data aggregation on the regulatory target data based on all cross-platform and cross-account identity mapping records to generate a cross-chain regulatory view. In this embodiment of the invention, the governance chain queries the identity mapping table based on the global digital identity identifier to determine all cross-platform and cross-account identity mapping records associated with the regulatory target data. Based on these records, it performs cross-platform data aggregation on the regulatory target data to generate a cross-chain regulatory view containing the complete behavioral trajectory of the same physical identity entity across multiple business chains. This cross-platform data aggregation uses the global digital identity identifier as the primary key and sorts and merges the regulatory target data obtained from different business chains in chronological order to form a unified regulatory data graph centered on the physical identity entity. The step of generating a cross-chain regulatory view containing the complete behavioral trajectory of the same physical identity entity across multiple business chains specifically includes the following sub-steps: Sub-step S5001: The governance chain uses the global digital identity identifier as the query key to retrieve all mapping records associated with the physical identity subject in the identity mapping table. Each mapping record contains a business chain identifier and its corresponding account address. The retrieval process utilizes a B+ tree index structure or hash index structure built with the global digital identity identifier as the main index in the identity mapping table to achieve fast lookup. The retrieval result returns a list of all cross-platform account addresses associated with the physical identity subject. Sub-step S5002: The governance chain sends cross-chain data query requests to the corresponding business chain based on the retrieved business chain identifier and account address combination, to obtain historical transaction records, smart contract interaction records, and account status change history related to the account address on each business chain; The cross-chain data query request adopts the Merkle tree proof mechanism, and the business chain returns response data containing transaction data and its corresponding Merkle path proof, so that the governance chain can verify the authenticity and completeness of the obtained data. The historical transaction records include the transaction initiator address, transaction receiver address, transaction amount or data content, transaction timestamp, and block hash of the block on which the transaction occurred; Sub-step S5003: The governance chain uses the global digital identity identifier as the associated primary key to sort and semantically fuse the historical transaction records, smart contract interaction records, and account status change history from different business chains according to timestamps, generating a cross-chain regulatory view of the complete behavioral trajectory across multiple business chain platforms centered on the physical identity subject. The semantic fusion includes normalizing and mapping transaction type fields with the same or similar semantics in different business chains, deduplicating and merging associated records of the same transaction behavior in different business chains, and unifying account address aliases or tags in different business chains. The cross-chain regulatory view is stored in the regulatory data warehouse of the governance chain in a graphical data structure or relational data table structure, supporting multi-dimensional filtering and querying by time range, business chain type, transaction type, and risk level.

[0029] S600. The governance chain, based on the cross-chain regulatory view and combined with a preset adaptive regulatory strategy library, performs adaptive regulatory analysis on the cross-chain behavior of the physical identity subject, generates regulatory decision results and executes corresponding regulatory disposal operations, and stores the regulatory decision results and disposal records on the chain for evidence.

[0030] In this embodiment of the invention, the governance chain, based on the cross-chain regulatory view and combined with a preset adaptive regulatory strategy library, performs adaptive regulatory analysis on the cross-chain behavior of the physical identity entity, generates regulatory decision results, and executes corresponding regulatory actions. The adaptive regulatory strategy library contains several regulatory rules, each defining triggering conditions, regulatory actions, and disposal measures. The governance chain dynamically matches the regulatory rules according to the characteristics of the behavioral trajectory in the cross-chain regulatory view, and executes at least one regulatory action based on the matching result, including alerting, freezing accounts, restricting cross-chain transactions, and reporting to regulatory agencies. Simultaneously, the regulatory decision results and disposal records are stored on the blockchain for evidence preservation.

[0031] The adaptive regulatory strategy library contains several regulatory rules, each defining triggering conditions, regulatory actions, and handling measures. The governance chain dynamically matches the regulatory rules based on the characteristics of behavioral trajectories in the cross-chain regulatory view, specifically including the following sub-steps: Sub-step S6001: The governance chain extracts the behavioral feature vector of the physical identity entity from the cross-chain regulatory view. The behavioral feature vector includes cross-chain transaction frequency characteristics, transaction amount distribution characteristics, counterparty diversity characteristics, transaction time distribution characteristics, and cross-platform account activity characteristics. The cross-chain transaction frequency characteristics include the total number of cross-chain transactions per unit time, the proportion of cross-chain transactions to the total number of transactions, and the statistical characteristics of cross-chain transaction intervals. The transaction amount distribution characteristics include the mean, variance, maximum and minimum values ​​of single transaction amounts, and the proportion of large transactions. The counterparty diversity characteristics include the entropy value of the number of counterparties and the frequency of new counterparties. The transaction time distribution characteristics include the time period distribution of transactions within a day and the date distribution pattern within a week. Sub-step S6002: The governance chain performs matching calculations between the behavior feature vector and the triggering conditions of each regulatory rule in the adaptive regulatory strategy library, calculates the matching degree between the behavior feature vector and the triggering condition of each regulatory rule, and selects the regulatory rule with the highest matching degree as the target regulatory rule; the matching calculation is implemented based on a vector space similarity algorithm or a decision tree-based classification algorithm, the triggering condition is defined in the form of a feature threshold combination or a feature logical expression, the matching degree is represented by a value between 0 and 1, when the highest matching degree is lower than the preset matching threshold, the governance chain adopts the default regulatory rule or triggers a manual review process; Sub-step S6003: The governance chain performs corresponding regulatory analysis operations on the cross-chain regulatory view according to the regulatory actions defined in the target regulatory rules, and executes the disposal measures defined in the target regulatory rules based on the analysis results. The regulatory analysis operations include at least one of the following: statistical analysis of the historical behavior data of the physical identity entity, anomaly detection of cross-platform behavior patterns, tracking and analysis of fund flows, and compliance checks on smart contract call parameters. The disposal measures include at least one of the following: generating regulatory alert notifications, adjusting the account permissions of the physical identity entity on a specific business chain, restricting the cross-chain transaction limit of the physical identity entity, adding the physical identity entity to the key regulatory list, and submitting a regulatory report to the regulatory agency. Sub-step S6004: The governance chain synchronizes the regulatory decision results and disposal records to each relevant business chain through the cross-chain middleware layer, and stores them on the governance chain. The synchronization operation adopts an eventual consistency distributed transaction mechanism. After completing the regulatory disposal, the governance chain generates a regulatory disposal record containing the disposal type, disposal object, disposal time, and disposal basis. The regulatory disposal record is packaged into a cross-chain message and sent to each relevant business chain through the cross-chain middleware layer. After receiving the cross-chain message, each relevant business chain performs the corresponding local state change operation and returns a confirmation receipt to the governance chain. After collecting all confirmation receipts or reaching the legally required number of confirmations within a preset timeout period, the governance chain writes the hash value of the regulatory disposal record into the storage block of the governance chain, so as to realize the traceability and immutability of the regulatory disposal results.

[0032] Example 2: A blockchain-based multi-chain regulatory system, such as Figure 2 As shown, it includes: Cross-chain supervision module 100 constructs a multi-dimensional cross-chain supervision architecture, which includes a governance chain, several business chains, and a cross-chain middleware layer. The identity mapping module 200 generates a global digital identity identifier for the physical identity subject based on the digital identity management contract of the governance chain, establishes a mapping relationship between the global digital identity identifier and multiple on-chain account addresses of the physical identity subject on various business chains, and forms an identity mapping table based on the mapping relationship. The credential construction module 300 constructs cross-platform association credentials between physical identity subjects and network identities based on the identity mapping table. The identity module 400 responds to a cross-chain regulatory trigger event. The governance chain obtains regulatory target data on the target business chain through the cross-chain middleware layer, queries cross-platform associated credentials based on the regulatory target data, and retrieves the global digital identity identifier of the regulatory target data. The cross-chain supervision module 500, wherein the governance chain queries the identity mapping table based on the global digital identity identifier to obtain all cross-platform and cross-account identity mapping records associated with the supervision target data, and performs cross-platform data aggregation on the supervision target data based on all cross-platform and cross-account identity mapping records to generate a cross-chain supervision view; The regulatory analysis module 600, based on the cross-chain regulatory view, combines a preset adaptive regulatory strategy library to perform adaptive regulatory analysis on the cross-chain behavior of the physical identity subject, generates regulatory decision results and executes corresponding regulatory disposal operations, and stores the regulatory decision results and disposal records on the blockchain for evidence.

[0033] Another embodiment of the present invention provides a computer-readable storage medium storing a computer program that, when executed by a processor, can perform the same or similar steps as in the method embodiment, which will not be repeated here.

[0034] The above description of the embodiments is provided to enable those skilled in the art to understand and apply the present invention. It will be apparent to those skilled in the art that various modifications can be made to the above embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made to the present invention by those skilled in the art based on the disclosure thereof should be within the scope of protection of the present invention.

Claims

1. A multi-chain regulatory method for blockchain, characterized in that, Includes the following steps: Construct a multi-dimensional cross-chain regulatory architecture, which includes a governance chain, several business chains, and a cross-chain middleware layer; Based on the digital identity management contract of the governance chain, a global digital identity identifier for the physical identity subject is generated, a mapping relationship is established between the global digital identity identifier and multiple on-chain account addresses of the physical identity subject on various business chains, and an identity mapping table is formed based on the mapping relationship. Based on the identity mapping table, a cross-platform association credential between the physical identity subject and the network identity is constructed; In response to a cross-chain regulatory trigger event, the governance chain obtains regulatory target data on the target business chain through the cross-chain middleware layer, queries cross-platform associated credentials based on the regulatory target data, and retrieves the global digital identity identifier of the regulatory target data. The governance chain queries the identity mapping table based on the global digital identity identifier to obtain all cross-platform and cross-account identity mapping records associated with the regulatory target data, and performs cross-platform data aggregation on the regulatory target data based on all cross-platform and cross-account identity mapping records to generate a cross-chain regulatory view; The governance chain, based on the cross-chain regulatory view and combined with a preset adaptive regulatory strategy library, performs adaptive regulatory analysis on the cross-chain behavior of the physical identity entity, generates regulatory decision results, executes corresponding regulatory disposal operations, and stores the regulatory decision results and disposal records on the chain for evidence.

2. The blockchain multi-chain regulatory method according to claim 1, characterized in that, The digital identity management contract based on the governance chain generates a global digital identity identifier for the physical identity subject, including the following steps: The physical identity entity submits an identity registration request to the governance chain through a trusted identity authentication channel; The governance chain calls the identity verification logic in the digital identity management contract to verify the authenticity of the identity information in the identity registration request, and after the verification is passed, generates a unique decentralized identity identifier for the physical identity subject based on the distributed digital identity identifier specification as the global digital identity identifier. The digital identity management contract derives a corresponding public-private key pair for the global digital identity identifier based on an asymmetric cryptographic algorithm, sends the private key of the public-private key pair to the terminal device of the physical identity subject through a secure channel, and binds the public key of the public-private key pair to the global digital identity identifier and stores it in the identity registry of the governance chain.

3. The blockchain multi-chain regulatory method according to claim 1, characterized in that, Establishing the mapping relationship between the global digital identity identifier and the physical identity subject's multiple on-chain account addresses on each business chain includes the following steps: When the physical identity subject creates or uses an on-chain account on any business chain, the business chain sends an account association request to the governance chain through the cross-chain middleware layer. The account association request includes the global digital identity identifier, the chain identifier of the business chain, and the account address on the business chain. The legitimacy of the account association request is verified according to the digital identity management contract of the governance chain; If valid, the digital identity management contract creates or updates a mapping record in the identity mapping table, associates and stores the global digital identity identifier, the chain identifier of the business chain, and the account address triplet on the business chain, and records the mapping establishment timestamp, mapping status, and mapping validity period; the identity mapping table supports searching by global digital identity identifier to obtain a list of all cross-platform account addresses associated with the physical identity subject, and performing reverse searching by business chain identifier and account address to obtain the corresponding global digital identity identifier.

4. The blockchain multi-chain regulatory method according to claim 1, characterized in that, The process of constructing a cross-platform association credential between a physical identity subject and a network identity based on the identity mapping table includes the following steps: The governance chain calls the verifiable credential generation service based on the mapping record in the identity mapping table, uses the global digital identity identifier as the credential holder identifier and the chain identifier of the governance chain itself as the credential issuer identifier, and constructs a declaration subject containing the global digital identity identifier, the target business chain identifier and the target account address. The governance chain uses its regulatory private key to digitally sign the claim subject, generate the verifiable claim, and encapsulate the verifiable claim and the claim subject into a complete verifiable credential. The governance chain distributes the verifiable credentials to the target business chain through the cross-chain middleware layer. When verifying the verifiable credentials, the target business chain first queries the governance chain for the latest status of the credentials through the cross-chain middleware layer to confirm that they have not been revoked. Then, it uses the pre-stored governance chain public key to verify the signature of the credentials. After the signature verification is successful, it extracts the account address in the claim subject and compares it with the current operating account address. If the comparison is consistent, it confirms that the physical identity subject has legitimate control over the account address.

5. The blockchain multi-chain regulatory method according to claim 1, characterized in that, In response to a cross-chain regulatory trigger event, the governance chain obtains regulatory target data from the target business chain through the cross-chain middleware layer, including the following steps: The cross-chain middleware layer configures a dedicated block listener for each business chain. The block listener connects to the network node of the business chain through the node application programming interface or light client protocol of the business chain and continuously listens for new block generation events of the business chain. In response to the detected new block generation event, the block listener parses the transaction list from the new block and extracts transaction data, smart contract call records and account status change information from the transaction list as the regulatory target data. At the same time, the regulatory target data is standardized in format and then reported to the governance chain through the cross-chain message protocol. The cross-chain middleware layer is also configured with a transaction log event listener, which is used to listen to event logs issued by smart contracts on each business chain that conform to the preset event signature specifications. When a target event log is detected, the transaction data and contract state change data associated with the event log are reported to the governance chain as supplementary regulatory target data.

6. The blockchain multi-chain regulatory method according to claim 1, characterized in that, The process of aggregating the regulatory target data across platforms based on all cross-platform and cross-account identity mapping records to generate a cross-chain regulatory view includes the following steps: The governance chain uses the global digital identity identifier as the query key to retrieve all mapping records associated with the physical identity subject in the identity mapping table. Each mapping record contains a business chain identifier and its corresponding account address. The governance chain sends cross-chain data query requests to the corresponding business chain based on the retrieved business chain identifier and account address combination, in order to obtain historical transaction records, smart contract interaction records and account status change history related to the account address on each business chain. The governance chain uses the global digital identity identifier as the associated primary key to sort and semantically fuse the historical transaction records, smart contract interaction records, and account status change history from different business chains according to timestamps, generating a cross-chain regulatory view of the complete behavioral trajectory across multiple business chain platforms centered on the physical identity subject.

7. The blockchain multi-chain regulatory method according to claim 1, characterized in that, The governance chain, based on the cross-chain regulatory view and combined with a pre-set adaptive regulatory strategy library, performs adaptive regulatory analysis on the cross-chain behavior of the physical identity entity, generates regulatory decision results, and executes corresponding regulatory actions, specifically including the following steps: The governance chain extracts the behavioral feature vector of the physical identity subject from the cross-chain regulatory view; A pre-defined adaptive regulatory strategy library is provided, which contains several regulatory rules. Each regulatory rule defines triggering conditions, regulatory actions, and handling measures. The governance chain performs matching calculations between the behavioral feature vector and the triggering conditions of each regulatory rule in the adaptive regulatory strategy library, calculates the matching degree between the behavioral feature vector and the triggering conditions of each regulatory rule, and selects the regulatory rule with the highest matching degree as the target regulatory rule. The governance chain performs corresponding regulatory analysis operations on the cross-chain regulatory view according to the regulatory actions defined in the target regulatory rules, and executes the disposal measures defined in the target regulatory rules based on the analysis results.

8. The blockchain multi-chain regulatory method according to claim 1, characterized in that, Also includes: The governance chain synchronizes the regulatory decision results and disposal records to the relevant business chains through the cross-chain middleware layer, and stores the evidence on the governance chain. The synchronization operation adopts an eventual consistency distributed transaction mechanism. After completing the regulatory action, the governance chain generates a regulatory action record. The regulatory action record includes the action type, action object, action time and action basis. The regulatory action record is packaged into a cross-chain message and sent to each relevant business chain through the cross-chain middleware layer. After receiving the cross-chain message, each relevant business chain performs the corresponding local state change operation and returns a confirmation receipt to the governance chain. Once the governance chain has collected all confirmation receipts or reached the legally required number of confirmations within a preset timeout period, it writes the hash value of the regulatory action record into the evidence storage block of the governance chain.

9. A blockchain-based multi-chain regulatory system, characterized in that, include: The cross-chain regulatory module constructs a multi-dimensional cross-chain regulatory architecture, which includes a governance chain, several business chains, and a cross-chain middleware layer. The identity mapping module generates a global digital identity identifier for the physical identity subject based on the digital identity management contract of the governance chain, establishes a mapping relationship between the global digital identity identifier and multiple on-chain account addresses of the physical identity subject on various business chains, and forms an identity mapping table based on the mapping relationship. The credential construction module constructs cross-platform association credentials between physical identity subjects and network identities based on the identity mapping table; The identity module responds to cross-chain regulatory trigger events. The governance chain obtains regulatory target data on the target business chain through the cross-chain middleware layer, queries cross-platform associated credentials based on the regulatory target data, and retrieves the global digital identity identifier of the regulatory target data. The cross-chain regulatory module involves the governance chain querying the identity mapping table based on the global digital identity identifier to obtain all cross-platform and cross-account identity mapping records associated with the regulatory target data, and then performing cross-platform data aggregation on the regulatory target data based on all cross-platform and cross-account identity mapping records to generate a cross-chain regulatory view. The regulatory analysis module, based on the cross-chain regulatory view and combined with a preset adaptive regulatory strategy library, performs adaptive regulatory analysis on the cross-chain behavior of the physical identity entity, generates regulatory decision results, executes corresponding regulatory disposal operations, and stores the regulatory decision results and disposal records on the blockchain for evidence.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the method as described in any one of claims 1 to 8.

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