A data tracking and tracing algorithm based on double blockchains in a meta universe background

Abstract

The application discloses a data tracking and tracing algorithm based on double blockchains under a meta universe background, in the first step, virtual data in the meta universe space is uploaded to a blockchain, i.e., a data chain, the hash value of the virtual data is calculated, and the hash value of the virtual data is stored in the data chain; in the second step, another blockchain, i.e., a hash chain, is introduced, and the hash chain and the data chain have a hash mapping; in the third step, a chameleon signature technology is introduced, the chameleon signature technology associates virtual roles in the meta universe with biological characteristics, tracking is performed through an identity parameter of the virtual role, and the identity parameter is used to track the source of a malicious virtual role. The application can solve the problems of difficult digital asset tracking and high tracing cost under the meta universe background, can improve the efficiency of tracing work, and adopts different tracing schemes for different digital assets, so that the traceability and safety of high-value-added assets are considered while the data tracing efficiency is ensured.

Description

TECHNICAL FIELD

[0001] The application relates to a meta-universe data tracking and tracing algorithm, in particular to a data tracking and tracing algorithm based on double blockchains in a meta-universe background. BACKGROUND

[0002] In 2017, Satchidanandan et al. proposed a dynamic watermarking technique that utilizes the indelible pattern of the imprint in the medium to detect the improper behavior of malicious sensors or actuators (such as signal tampering). In addition, advanced watermarking technology can also be used to realize intellectual property protection and ownership authentication in the meta-universe. However, dynamic watermarking technology is suitable for scenarios with high requirements for copyright protection and content tracking, and its implementation and calculation cost is relatively high, which is not suitable for large volume of digital assets in the meta-universe environment.

[0003] The next year, sin et al. designed a lightweight protocol to realize data tracing in wireless communication, in which a unique link fingerprint is generated by using the RSS (received signal strength) indicator of the communication Internet of Things node. The link fingerprint is matched on the server side to calculate the correlation coefficient. The higher the correlation coefficient value, the higher the percentage of secure data transmission. A lower value gives the detection of adversarial nodes between specific links. By comparing the data packet header with all available link fingerprints on the server, the source of the data can also be obtained. However, this scheme needs a centralized server to perform data tracing operation, and the widespread use of blockchains in the meta-universe makes this scheme not applicable.

[0004] In 2021, Wang et al. proposed a secure and auditable private data sharing scheme in the data processing as a service (DPaaS) mode in the smart grid. The scheme first proposes a blockchain-based framework for trustless private data computation and data usage tracking. Smart contracts are used to specify fine-grained data usage policies, while distributed ledgers keep immutable and transparent records of data usage. However, relying solely on distributed ledgers to complete the tracing task will result in low efficiency of tracing, often requiring traversal of the entire ledger to track the publisher of the digital asset, which will require a large time cost.

[0005] In 2022, Zhenyong Zhang et al. proposed a two-factor authentication framework based on chameleon signature and biometric authentication, aiming to ensure the traceability of virtual roles in the metaverse. This algorithm allows players to sign multiple virtual roles using a pair of keys, improving computational efficiency and reducing storage costs. This algorithm is suitable for high-value digital assets, and in the architecture of this algorithm, it can be used as part of the traceability work for high-value assets.

[0006] In 2023, Xiao et al. proposed a new lightweight TCM traceability architecture based on sharded blockchain (LBS-TCM). However, this solution is designed for a central server, and the lightweight blockchain works with different sharded networks, which is not suitable for the metaverse environment.

[0007] In the same year, Harish A R et al. introduced a blockchain-based physical traceability system for logistics financing based on digital asset tokenization. Tokenization of digital assets brings visibility and traceability to the supply chain's network (information flow) and physical (logistics flow) transactions. However, this solution still requires tokenization of all digital assets, which is no different from traditional digital signature methods, and does not have the advanced nature of this algorithm to trace digital assets using the blockchain itself.

[0008] In 2024, Elapolu et al. proposed a new blockchain-based demand traceability framework, which includes a data acquisition template and a graph-based visualization. However, this algorithm is implemented on a small-scale dataset, and the effectiveness of this algorithm for large-scale digital assets in the metaverse environment has not been verified.

[0009] Due to the lack of a trusted third-party server as an official verification platform in the metaverse environment, there is a demand for tracing a large number of digital assets, and in order to protect the copyright of digital asset owners, an efficient traceable and traceable mechanism needs to be established to track the transmission process of data and trace it to specific data generation and modification operations. SUMMARY

[0010] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a data tracking and tracing algorithm based on double blockchain in the metaverse background. The present invention can solve the problems of difficult digital asset tracking and high traceability cost in the metaverse background, improve the efficiency of traceability work, and adopt different traceability solutions for different digital assets to meet the needs of users in different metaverse backgrounds, while ensuring data traceability efficiency, taking into account the traceability and security of high-value assets.

[0011] To solve the above technical problems, the technical scheme adopted by the present application is:

[0012] A data tracking and tracing algorithm based on double blockchains in the metaverse background, first, upload the virtual data in the metaverse space to a blockchain, i.e., data chain, calculate the hash value of the virtual data, and store the hash value of the virtual data in the data chain; second, introduce another blockchain, i.e., hash chain, which has a hash mapping with the data chain.

[0013] Preferably, a third step is introduced, i.e., chameleon signature technology, which associates the virtual character of the metaverse with the biological characteristics, tracks through the identity parameter of the virtual character, and traces the source of the malicious virtual character using the reserved identity parameter.

[0014] Preferably, the hash chain stores the information of the line label, and a smart contract is used for scheduling, each hash value is derived from the previous value, and the hash chain can quickly locate the block where the data is located in the data chain.

[0015] Preferably, the hash chain uses image replacement to connect nodes, and the order between nodes is determined by voting.

[0016] Preferably, the chameleon signature technology is combined with the authentication of the biological characteristics for two-factor authentication, which can realize the verifiability of the virtual identity of the virtual avatar, and based on the biological feature template of the player and the chameleon key, an identity model of the virtual character is constructed to realize the verifiability of the physical identity of the virtual character.

[0017] Preferably, before the first step, the virtual data of the metaverse is screened into general data and important data, the general data uses double blockchains, and the important data uses chameleon signature technology.

[0018] Preferably, the important data is signed using the chameleon signature technology, the biological characteristics of the user in the metaverse are associated with the important virtual data, and on this basis, an operation log is established for the important data to record all subsequent operations of the user on the important data and subsequent transaction information.

[0019] Preferably, the hash chain in the double-layer blockchain first locates the block information of the data to be traced according to the line label information, and at the same time, according to the inherent characteristics of the blockchain, all operation records of the data can be retrieved, in this step, all operations and transaction information of the data can be obtained, and the basic tracing requirement is completed.

[0020] Preferably, the original data itself is queried, and the information of the uploading user of the data is traced, then the corresponding block on the data chain is directly found through the position of the block obtained in the hash chain, and then the hash value of the virtual data, that is, the complete content of the virtual data is obtained, and the user identity of the publisher is locked according to the record of the uploader in the data chain, so as to complete the tracing task of the virtual data.

[0021] Preferably, the complete data content is extracted by calling the hash value of the chameleon signature of the data, and then the relevant information of the owner of the data is obtained, and all operation records and transaction information of important data are obtained through the record of the operation log; considering that the operation design involves the privacy security of the user, therefore, the reading of the hash value of the chameleon signature and the operation log need to be called by the secret key of a trusted third party such as a metaverse service provider, so as to prevent any user on the blockchain from being able to view this part of information and then infringe the privacy security of the virtual data owner.

[0022] The present application has the following beneficial effects:

[0023] In order to realize the tracing operation of data and operation records after the fusion of virtual data in the metaverse background, the present application introduces a dual blockchain (Dual Blockchain) architecture and a chameleon signature (Chameleon Signature) technology to quickly locate and verify a specific data set by tracking a hash chain, so as to realize the traceability of the dual-layer blockchain, and the efficiency of data and operation record tracing is significantly improved; the chameleon signature technology associates the avatar of the user in the metaverse with a digital signature, and traces through the identity parameter of the virtual role, and traces the source of the malicious virtual role by using the reserved identity parameter, but the required calculation overhead of the method is relatively large, so the method is only used for important data, and the dual blockchain architecture is still used for general data to realize the traceability of the virtual data. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 is a schematic diagram of the dual blockchain in the present application.

[0025] Figure 2 is a schematic diagram of the hash chain in the present application.

[0026] Figure 3 is a flowchart of data storage and data tracing in the metaverse background of the present application.

[0027] Figure 4 is a dual blockchain model built in the remix platform and a common smart contract written to calculate the gas value consumption required for deployment of the smart contract, and a cost example result graph.

[0028] Figure 5 To show the solidity language implementation of the smart contract.

[0029] Figure 6 For the selection of the virtual environment and the deployment of the blockchain.

[0030] Figure 7 For the "test" data stored in the block, that is, there is a transaction to store data in the block, and the corresponding transaction cost, that is, the gas value, can be obtained. In this way, the cost overhead required by the block deployed by the present application can be obtained.

[0031] Figure 8 For building a sawtooth docker environment in an Ubuntu virtual environment, simulating the process of data transaction in a local virtual environment, and then obtaining the running time and execution efficiency data of the algorithm.

[0032] Figure 9 For example, according to the requirements of the official configuration file of sawtooth, different consensus algorithms are written, taking the Byzantine consensus mechanism (PBFT) as an example.

[0033] Figure 10 For subsequent environment setup, build a blockchain in a virtual Docker. After the block is built, all transaction record information in the current block will be printed in the terminal.

[0034] Figure 11 The results of the retrieval and storage data query data of all users in the blockchain are shown; subsequently, the effect of the present application is tested for different block quantities, and the time cost required by the present application under different block quantities. DETAILED DESCRIPTION

[0035] The present application will be further described in detail below in combination with the drawings and specific preferred embodiments.

[0036] Virtual data, in the meta-universe environment, virtual data will have various forms, such as pictures, audio and video, text and other multi-modal forms, which do not affect the subsequent traceability operation, so they can be transmitted together to the meta-universe space without classification.

[0037] Dual blockchain (Dual Blockchain) architecture, as follows Figure 1As shown, all virtual data is first uploaded to the data chain, and the process mainly involves calculating the hash value of the virtual data and storing the hash value of all data in the data chain, so that the hash value of all original virtual data can be retrieved in the data chain, i.e., all original virtual data can be retrieved. On this basis, another blockchain is introduced, named hash chain. There is a hash mapping between the blockchain and the data chain, and information such as line markers will be stored. The blockchain is scheduled by a smart contract alone, and each hash value is derived from the previous value. The blockchain can ensure that the hash chain can quickly locate the block where a certain data in the data chain is located. The specific structure of the hash chain is shown in Figure 2 Unlike traditional linear blockchains, the hash chain uses a directed acyclic graph (DAG) to connect nodes, and the order between nodes is determined by voting. The blockchain mainly uses the asynchronous Byzantine fault tolerance (ABFT) mechanism to propagate transactions through the underlying broadcast protocol, i.e., each node can randomly select another node for synchronization. After creating a new event in the blockchain, the round of the node where the event is located is determined according to whether the current node is visible to more than 2 / 3 of the nodes in the previous round. After determining the round of all nodes, the first event in each round is voted to verify whether it is famous (i.e., whether it is approved by more than 2 / 3 of the nodes). Finally, the famous nodes are sorted according to the round information, which corresponds to the line information described below. If the round information is the same, the nodes can be sorted according to the timestamps established by different nodes. After the hash chain is established, for example, when we need to locate the node in line A, we do not need to traverse the traditional linear blockchain to track the data in the node. With the help of the hash chain, we can quickly locate the target we need to track from line A according to the line marker, which can greatly improve the tracking efficiency of the tracing algorithm.

[0038] Chameleon signature technology, also known as chameleon signature technology, mainly combines with biometric authentication two-factor authentication. This digital signature technology mainly targets the camouflage problem in virtual space and can achieve the verifiability of virtual avatar virtual identity. It is mainly based on the biometric template of the player and the chameleon key to build an identity model of the virtual character, realizing the verifiability of the physical identity of the virtual character. Any attempt to forge the identity of the virtual character needs to forge the biometric features and the corresponding check parameters, which is very difficult without the chameleon private key. Therefore, this framework provides a mechanism to track the source of malicious virtual characters through the preserved identity parameters.

[0039] As shown in Figure 3 The tracking algorithm process for data storage and operation records is as follows:

[0040] In the storage stage of virtual data in the metaverse, as shown inFigure 3 As shown in the data storage, firstly, the user-uploaded data and operation records are classified into general data and important data according to the importance, and the classification mechanism is mainly defined by the user, for example, when uploading data into the metaverse environment, the user needs to divide the importance of the virtual data according to his own needs, and the label of the division will be added to the virtual data in a binary way, and the label value can be directly queried to distinguish the importance of different data. If it is general data, calculate the hash value of the data, and record the unique hash value to the data chain in the double-layer blockchain architecture; if it is important data, use the chameleon signature technology to sign the important data, associate the user's biological characteristics in the metaverse with the important virtual data, and on this basis, establish an operation log for the important data to record all subsequent user operations on the important data and subsequent transaction information.

[0041] In the traceability stage, as shown in the data traceability, Figure 3 As shown in the data traceability, the tracing algorithm process of data and operation records is as follows:

[0042] After the problem data is found, the corresponding importance label of the virtual data can be obtained through the classification mechanism mentioned earlier, so as to divide the importance of the data that needs to be traced. If the data is general data, the hash chain in the double-layer blockchain can first locate the block information of the data to be traced according to the line label information, that is, obtain the specific position of the data in the data chain. At the same time of locating the data in the hash chain, all operation records of the data can be retrieved according to the inherent characteristics of the blockchain. In this step, all operations and transaction information of the data can be obtained, and the basic traceability requirement is completed. If the original data itself and the information of the user who uploaded the data need to be queried, the corresponding block on the data chain can be directly found through the position of the corresponding block on the data chain obtained from the hash chain, and then the hash value of the virtual data, that is, the complete content of the virtual data is obtained, and the user identity of the publisher is locked according to the uploader's record in the data chain, so as to complete the traceability task of the virtual data. If the classified result is important data, the complete data content can be extracted by retrieving the chameleon signature hash value of the data, and then the information of the owner of the data is obtained, and all operation records and transaction information of the important data can be obtained through the operation log record. Considering the privacy and security of the user in this operation, the reading and operation log of the chameleon signature hash value need to be retrieved by the secret key of the trusted third party such as the metaverse service provider, so as to prevent any user on the blockchain from being able to view this part of information and thus infringe the privacy and security of the virtual data owner.

[0043] The reason why the double blockchain structure combining the data chain and the hash chain must be adopted is that there will be a transaction behavior for virtual data under the background of the metaverse. If a single data chain or hash chain is adopted, the transaction behavior for virtual data will cause the same data to generate different transaction blocks stored on different blocks in the blockchain. Then, in the process of blockchain tracing, the entire blockchain needs to be traversed to obtain the relevant information of the original publisher of the virtual data, i.e., the source of the virtual data. Through the double blockchain structure, this problem can be solved in a two-dimensional form. Through the mapping relationship of the hash chain to the data chain, the block where the transaction behavior of uploading data is located in the data chain can be directly located, and then the source information of the data is determined.

[0044] Firstly, a double blockchain model is built in the remix platform and common smart contracts are written to calculate the gas value consumption (deployment cost) required for smart contract deployment. The specific process is that, on the existing remix blockchain building platform, user identity authentication, data uploading, data querying, data transaction, data tracing, cross-chain communication and other smart contracts are written, and the smart contracts are implemented using the Solidity language; and the existing functions of the platform, i.e., the virtual environment of Remix VM (Shanghai), are used for blockchain deployment; the gas cost results brought by the operations in the block are demonstrated in the subsequent pictures. The cost example results are as shown in Figure 4 . Figure 5 The solid ity language is used to implement the smart contract. Figure 6 The virtual environment is selected and the blockchain is deployed. Figure 7 For example, the "test" data is stored in the block, i.e., there is a transaction of storing data in the block, and the corresponding transaction cost, i.e., the gas value, can be obtained. In this way, the cost overhead of the deployed block of the application can be obtained.

[0045] Secondly, the sawtooth docker environment is built in the Ubuntu virtual environment to simulate the process of data transaction in the local virtual environment, and then the running time and execution efficiency data of the algorithm are obtained. The result example is as shown in Figure 8 . The specific process is that, according to the official configuration file requirements of sawtooth, different consensus algorithms are written, taking the Byzantine consensus mechanism (PBFT) as an example, as shown in Figure 9 ; then the required environment is built, and the blockchain is built in the virtual Docker. After the block is built, all transaction record information in the current block will be printed in the terminal, as shown in Figure 10 ; on this basis, data storage and tracing operations can be performed in the blockchain, as shown in Figure 11The results of the call to all users in the blockchain and the feedback of the result of the data query are shown; subsequently, the effect of the application is tested for different block quantities, and under different block quantities, the time required by the architecture. Embodiments

[0046] Examples of actual data traceability are cited.

[0047] First, in the cloud universe background, the legitimate user wants to upload local data to the metaverse, and needs to define the importance of his own data, using a binary tag to mark important data as 1 and general important data as 0. After uploading the data to the metaverse, a trusted third party (the provider of the metaverse service) will generate a pair of keys for each data, denoted as key1, one part of which is owned by the trusted third party and the other part is owned by the data owner. The key key1 is mainly used to retrieve the original content of the virtual data according to the hash value, and this information can only be obtained by the trusted third party and the data owner, in order to maintain the ownership of the virtual data, and the hash function is used to calculate the hash value of the virtual data, denoted as hash alpha. If the importance label value of the data is 1 (important data), a digital signature hash calculation result of the chameleon front technology will be added to the hash value of the data, denoted as hash beta, and hash beta will be integrated into the biological characteristics of the data user, in order to confirm the identity information of the virtual data owner. At the same time, a record is generated in the operation log for the important data, including the operation of the data owner uploading the data, and subsequent data transactions or data change behaviors will be recorded in the operation log. The operation log can only be accessed by the trusted third party and the data owner through the key key1.

[0048] If the importance label value of the data is 0 (general data), the hash value of the data will be uploaded to the block of the data chain, and the hash value of the data in the data chain and the information of the block where the data is located are packaged and stored in the hash chain. In the process of adding to the hash chain, the order of the new node needs to be determined through the voting results of other nodes. After the new node successfully joins the blockchain, the corresponding line label result will be assigned for fast lookup of the hash chain, and then the subsequent hash chain realizes the fast positioning and query operation task of the data chain. If there is a data transaction or data change behavior later, it will be recorded in the hash chain in the form of generating a new node. It should be noted that the data chain itself is open to all users in the metaverse, and everyone can see the hash value of different virtual data and all transaction records, but only the hash value cannot obtain the content of the data itself; accordingly, in the hash chain, only the trusted third party and the owner of the data have the right to obtain the information of the block in the hash chain. This operation is mainly realized through a smart contract, which limits the reading permission of users in different blockchains to the information in the block.

[0049] At this point, the data storage process is basically completed.

[0050] If there is a malicious transaction or malicious data, or the data buyer needs to verify the legal ownership of the transaction data during the user transaction process, or there is an infringement behavior, the ownership of the virtual data needs to be traced back, and the evidence is used for the identification of the arbitration institution, then the following data tracing operation needs to be performed.

[0051] First, according to the information of the data itself, the importance label of the data can be obtained. If the importance label value is 1 (important data), the trusted third party can retrieve and decrypt the chameleon signature information of the important data according to the secret key key1, and then determine the identity information of the owner of the virtual data. In addition, the operation log can be called to query all operation records and transaction information of the important data, and the data tracing task is completed. If the importance label value is 0 (general data), the trusted third party can use the line label information of the data to quickly locate the relevant information of the data (mainly obtain the block information in the data chain) from the hash chain, including the historical transaction information and operation records of the data, and then call the corresponding block in the data chain to obtain the publisher of the virtual data, that is, the data tracing task of the virtual data is completed.

[0052] The preferred embodiments of the application are described in detail above, but the application is not limited to the specific details in the above embodiments. Within the technical concept of the application, various equivalent transformations of the technical solutions of the application can be made, and these equivalent transformations all belong to the protection scope of the application.

Claims

1. A data tracking and tracing method based on dual blockchains in the context of the Metaverse, characterized by: The first step is to filter the virtual data of the metaverse and divide it into general data and important data. The general data uses dual blockchains, and the important data uses chameleon signature technology. The virtual data in the metaverse space is uploaded to a blockchain, i.e., the data chain, and the hash value of the virtual data is calculated and stored in the data chain. The second step is to introduce another blockchain, the hash chain, which has a hash mapping with the data chain. The third step is to introduce the Chameleon Signature technology. Chameleon Signature technology associates the virtual characters of the Metaverse with biometrics, tracks them through the identity parameters of the virtual characters, and uses the retained identity parameters to track the source of malicious virtual characters. Among them, Chameleon Signature technology is used to sign important data, linking the biometrics of users in the Metaverse with important virtual data. On this basis, an operation log is created for this important data to record all subsequent user operations on this important data and subsequent transaction information; The hash chain stores line mark information and is scheduled using a separate smart contract. Each hash value is derived from the previous value, and the hash chain can quickly locate the block where a certain data is located in the data chain. The hash chain in the two-layer blockchain first locates the block information of the data that needs to be traced based on the line tag information. At the same time, due to the inherent characteristics of the blockchain, all operation records of the data can be retrieved. In this step, all operations and transaction information on the data can be obtained, completing the traceability requirement. Once the original data itself and the information tracing back to the user who uploaded the data are found, the corresponding block on the data chain can be directly found through the location of the corresponding block on the data chain already obtained in the hash chain, and the hash value of the virtual data, that is, the complete content of the virtual data, can be obtained. The user identity of the publisher can be locked according to the record of the uploader in the data chain to complete the task of tracing the virtual data.

2. The data tracking and tracing method based on dual blockchains in the context of the Metaverse according to claim 1 is characterized by: The hash chain uses a directed non-transitional graph to connect nodes, and the order between nodes is determined by voting.

3. The data tracking and tracing method based on dual blockchains in the context of the Metaverse according to claim 1 is characterized by: The combination of chameleon signature technology and biometric two-factor authentication can address the problem of disguise in virtual space and achieve the verifiability of the virtual identity of the virtual avatar; the identity model of the virtual character is built based on the player's biometric template and chameleon key to achieve the verifiability of the virtual character's physical identity.

4. The data tracking and tracing method based on dual blockchains in the context of the Metaverse according to claim 1 is characterized by: By directly retrieving the hash value of the chameleon signature of the data, the complete data content can be extracted, and then the relevant information of the owner of the data can be obtained. All operation records and transaction information for important data can be obtained through the operation log records. Considering that this operation involves the privacy and security of the user, the reading of the hash value of the chameleon signature and the operation log require the secret key of a trusted third party such as the metaverse service provider to prevent any user on the blockchain from being able to view this part of the information and thus infringe the privacy and security of the virtual data owner.

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