Large-scale distributed intelligent terminal trusted data aggregation method and system

Abstract

The invention discloses a trusted data aggregation method and system for a large-scale distributed intelligent terminal. The method comprises the following steps: step 1, initializing and defining public parameters and private parameters of each entity of an access layer; step 2, the intelligent terminal of the end layer converts the multi-dimensional data into single data for encryption and signature by using the parameters in the step 1), sends the encrypted data and the signature to an edge aggregator of the edge layer, and sends the signature to a block chain of the chain layer at the same time; step 3, an edge aggregator of the edge layer performs weighted aggregation on the encrypted data in the step 2), aggregates signatures, and sends the signatures to a control center of the cloud layer and a block chain of the chain layer; and step 4, the control center of the cloud layer decrypts by using the aggregated data in the step 3) to obtain a single-dimensional data aggregation value, and the block chain of the chain layer performs signature verification by using the aggregated signature value sent in the step 3) and the single-dimensional data aggregation value decrypted by the control center.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of data security, and particularly relates to a large-scale distributed intelligent terminal trusted data aggregation method and system. BACKGROUND

[0002] Distributed intelligent terminals are distributed in various places, such as smart grids, vehicle networks, smart factories, and smart parking lots. The security levels of these places are different, and intelligent terminals are vulnerable to attack threats. An adversary can obtain the activities and behaviors of users by obtaining the data sent by intelligent terminals, thereby infringing on the privacy of users. Therefore, how to protect the privacy of users is a key consideration for the deployment of intelligent terminals. Many existing data aggregation schemes have been proposed to solve the privacy and security problems of intelligent terminal data. For example, an aggregator aggregates the user data in a region together and sends it to a control center. After the data is aggregated, the data of a single user cannot be restored, thus protecting the privacy of a single user. The current main methods of data aggregation are homomorphic encryption and encryption based on masks. In recent years, blockchain technology has developed rapidly. As a distributed ledger, blockchain has the properties of non-tamperability and anonymity, and is widely used in distributed scenarios.

[0003] Chinese patent application No. 202311223364.1 proposes a smart grid data aggregation method and system based on a security mask, which improves the security and efficiency of the data aggregation scheme. Based on the encryption of the mask, the mask value is sent to the user and the aggregator in advance, and the user adds the mask value when encrypting to hide the original data. The aggregator deletes the added mask value when aggregating, thereby obtaining the correct aggregated data. However, this method has two defects: 1) because of the added step of adding the mask value, the computational overhead of the scheme is greatly increased; and 2) the data of each user is changed due to the addition of the mask value, which brings great hidden dangers to subsequent data processing. SUMMARY

[0004] In view of the above problems existing in the prior art, the present application provides a large-scale distributed intelligent terminal trusted data aggregation method and system. The present application can divide data according to user attributes, and at the same time realize the aggregation of multi-dimensional data, thereby reducing the computational overhead of data aggregation. In particular, the technical scheme of the present application can ensure correct data aggregation in the case of dishonest aggregation nodes, thereby providing security protection for subsequent data analysis. The present application is particularly suitable for application scenarios such as smart grids, vehicle networks, and smart cities. Compared with traditional data aggregation methods, the present application greatly improves the scalability, reliability, and efficiency of the system.

[0005] The present application adopts the following technical scheme:

[0006] A large-scale distributed intelligent terminal trusted data aggregation method, the specific steps of which are as follows:

[0007] Step 1: Initialization, defining public parameters and private parameters for each entity in the access layer;

[0008] Step 2: Using the parameters from Step 1), the smart terminal at the edge layer converts multi-dimensional data into single data for encryption and signing, and sends the encrypted data and signature to the edge aggregator at the edge layer, while also sending the signature to the blockchain at the chain layer.

[0009] Step 3: The edge aggregator of the edge layer performs weighted aggregation on the encrypted data of Step 2), and simultaneously aggregates the signatures and sends them to the control center of the cloud layer and the blockchain of the chain layer.

[0010] Step 4: The cloud layer's control center decrypts the aggregated data from step 3) to obtain a single-dimensional data aggregation value. The blockchain in the chain layer uses the aggregated signature value sent in step 3) and the single-dimensional data aggregation value decrypted by the control center to perform signature verification.

[0011] Preferably, in step 1, the public parameters include multiplicative cyclic groups, bilinear pairing maps, Paillier cryptosystems, and super-incrementing sequences, while the private parameters include the entity's private key.

[0012] Preferably, step 1 is as follows:

[0013] 1) The key generation center is selected from two multiplicative cyclic groups of order p. Set up a group Let g be a generator, and then from the group Randomly select elements θ, sk′, g j Let 1 ≤ j ≤ k, and define a bilinear mapping. The parameters of the Paillier cryptosystem are set by selecting two large prime numbers {q1, q2} that satisfy gcd(q1q2, (q1-1)(q2-1)) = 1, where gcd is the greatest common divisor; public parameters N = q1q2 and ρ = N+1 are set, along with the system master private key (private parameter) λ = lcm(q1-1, q2-1); four hash functions are defined at the key generation center. and

[0014] 2) The key generation center is based on the integer group. The private key v of the randomly selected smart terminal i (i = 1, 2, ..., l) and the public key And generate the private key for the control center. satisfy And calculate auxiliary parameters The key generation center deploys a pseudo-random number generator. Among them, SKprg It is a set of private keys, and nonce is a random number;

[0015] 3) The key generation center defines l parameters μ of the super-incrementing sequence. j Satisfying equation (1.1), where ξ j It is the maximum value of the j-th dimension, mod1 = 1;

[0016]

[0017] 4) The key generation center will combine {v0, sk′} and {v i g j The parameters {N, ρ, g, e, θ, H1, H2, H3, H4, σ} are sent to the control center and the smart terminal respectively, broadcasting common parameters {N, ρ, g, e, θ, H1, H2, H3, H4, σ}. i ,sk′,g j ,prg}.

[0018] Preferably, step 2 is as follows:

[0019] 1) Smart terminals will integrate multi-dimensional data mi j转 Transform into And calculate the ciphertext as shown in equation (1.2), where T is the timestamp;

[0020]

[0021] 2) The intelligent terminal calculates the auxiliary parameter δ i , of which; ID i For the pseudo identity of the i-th smart terminal,

[0022]

[0023] and tags i ;

[0024]

[0025] 3) The smart terminals send information {C} respectively. i ,T,δ i , tag i} and {T, δ i , tag i} For edge aggregators and blockchain.

[0026] Preferably, step 3 is as follows:

[0027] 1) The edge aggregator calculates the aggregated ciphertext C, as shown in equation (1.5).

[0028]

[0029] 2) The edge aggregator randomly selects two integers, nonce and sk. prg ∈SK prg Use the random number generator prag to generate l-1 random numbers prag(sk) prg , nonce)→{π1, π2,...,π l-1}, and set Then the edge aggregator calculates two auxiliary parameters δ and σ, as shown in equations (1.6) and (1.7);

[0030]

[0031] Where, π i It is a random number, an auxiliary parameter.

[0032] 3) The edge aggregator sends information {C, T} and {δ, σ, nonce, sk} respectively. prg} For the control center of the cloud layer and the blockchain of the chain layer.

[0033] Preferably, step 4 is as follows:

[0034] 1) The control center uses the private key v0 to calculate W, as shown in equation (1.8);

[0035]

[0036] set up There are (1+N) E =1 + N·E (mod N) 2 Therefore, E = (W-1) / N; then for each modulus μ j Calculate E divided by μ j The remainder gives the aggregate value m of each dimension of the data. j =E mod μ j ;

[0037] 2) Blockchain utilizes a pseudo-random function generator prag(sk) prg , noce) generates {π1, π2,...,π l-1}, then calculate π l As shown in equation (1.9);

[0038]

[0039] Verify whether equation (1.10) holds true. If it does, it means that the data has been correctly aggregated.

[0040]

[0041] This invention also discloses a large-scale distributed intelligent terminal trusted data aggregation system for performing the above method, comprising the following modules:

[0042] Initialization module: Defines public parameters and private parameters for each entity in the access layer;

[0043] Data encryption module: Using the parameters in the initialization module, the smart terminal at the end layer converts multi-dimensional data into single data for encryption and signing, and sends the encrypted data and signature to the edge aggregator at the edge layer, while also sending the signature to the blockchain at the chain layer;

[0044] Data aggregation module: The edge aggregator in the edge layer performs weighted aggregation of the encrypted data in the data encryption module, and also aggregates the signatures and sends them to the control center in the cloud layer and the blockchain in the chain layer.

[0045] Data decryption module: The cloud layer's control center uses the aggregated data in the data aggregation module to decrypt and obtain a single-dimensional data aggregation value. The blockchain in the chain layer uses the aggregated signature value sent by the data aggregation module and the single-dimensional data aggregation value decrypted by the control center to perform signature verification.

[0046] Compared with the prior art, the present invention has the following technical effects:

[0047] This invention proposes a five-layer system model, which consists of five layers: access layer, cloud layer, terminal layer, edge layer, and terminal layer, providing a clearer description of the workflow for large-scale distributed intelligent terminal data aggregation.

[0048] Based on the traditional security model, this invention considers the situation where aggregators may dishonestly aggregate data due to cost or other reasons. Under this security model, this invention proposes a signature verification scheme that ensures the correct and complete aggregation of data, thereby safeguarding the security and integrity of the data.

[0049] This invention proposes a novel data aggregation technology that enables weighted multidimensional data aggregation. By utilizing super-incrementing sequences to process multidimensional data, the computational overhead of multidimensional data processing is effectively reduced, ensuring that the solution is adaptable to performance-constrained devices. By using weighting factors to weight different data, the value of data with different attributes is distinguished, and data aggregation is performed more rationally. Attached Figure Description

[0050] Figure 1 The preferred embodiment of the present invention shows the computational overhead of the intelligent terminal during the experiment.

[0051] Figure 2 The preferred embodiment of the present invention provides an experimental calculation overhead diagram of the edge aggregator.

[0052] Figure 3A preferred embodiment of the present invention shows the blockchain gas consumption during experiments.

[0053] Figure 4 The preferred embodiment of the present invention relates to a structural model diagram of a large-scale distributed intelligent terminal trusted data aggregation method.

[0054] Figure 5 A block diagram of a large-scale distributed intelligent terminal trusted data aggregation system according to a preferred embodiment of the present invention. Detailed Implementation

[0055] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0056] like Figure 4 As shown, this embodiment first proposes a five-layer system model, including an access layer, a cloud layer, a chain layer, an edge layer, and an endpoint layer. The access layer consists of various entities with access permissions to aggregated data, such as governments, research institutes, and schools. These entities quickly locate and handle faults by analyzing regional data. The cloud layer consists of cloud servers with various functions, such as decryption centers, decision centers, control centers, and storage centers. These centers ensure the correct recovery and storage of aggregated data and perform simple data processing, such as calculating averages and variances. After data processing, the decision center can perform data analysis and other functions. It also verifies entity identity and data integrity to ensure data integrity and security. The chain layer mainly includes verification modules, access modules, and storage modules, verifying entity identity and data integrity to ensure data integrity and security. The edge layer mainly includes multiple edge aggregators that receive data from all terminals within their own region, obtain aggregation results, and then upload the results to the cloud layer and chain layer. The endpoint layer consists of various users, including terminal devices in various application scenarios, collecting terminal data and sending it to the edge layer. Under the above system model, in this embodiment of a large-scale distributed intelligent terminal trusted data aggregation method, the terminal layer, edge layer, cloud layer, and chain layer entities are respectively the intelligent terminal, edge aggregator, control center, and blockchain. The technical solution of this embodiment can be described in the following four stages.

[0057] 1. System Initialization

[0058] In this step, the system is initialized, and the common parameters of the scheme and the private parameters of each entity are defined, including common parameters such as multiplicative cyclic groups, bilinear pairing mappings, Paillier cryptosystems, and hyperincrementing sequences, as well as the private keys of each entity.

[0059] In this step, the key generation center is a trusted third party that initializes the system, sets parameters for various entities, ensures correct protocol initialization, and supports operations in subsequent stages. 1) The key generation center selects two multiplicative cyclic groups of order p. Set up a group Let g be a generator, and then from the group Randomly select elements θ, sk′, g j (1≤j≤k), and define a bilinear mapping. The parameters of the Paillier cryptosystem are set by selecting two large prime numbers {q1, q2} that satisfy gcd(q1q2, (q1-1)(q2-1)) = 1, where gcd is the greatest common divisor. Public parameters N = q1q2 and ρ = N+1, and the system master private key λ = lcm(q1-1, q2-1), are set. The key generation center defines four hash functions. and

[0060] 2) The key generation center is based on the integer group. The private key v of the randomly selected smart terminal i (i = 1, 2, ..., l) and the public key And generate the private key for the control center. Its satisfaction And calculate auxiliary parameters The key generation center deploys a pseudo-random number generator. Among them, SK prg It is the set of private keys, and nonce is a random number.

[0061] 3) The key generation center defines l parameters μ of the super-incrementing sequence. j Satisfies equation 1.1, where ξ j It is the maximum value of the j-th dimension data, mod1 = 1.

[0062]

[0063] 4) The key generation center will combine {v0, sk′} and {v i g j The parameters {N, ρ, g, e, θ, H1, H2, H3, H4, σ} are sent to the control center and the smart terminal respectively, broadcasting common parameters {N, ρ, g, e, θ, H1, H2, H3, H4, σ}. i ,sk′,g j ,prg}.

[0064] 2. Data encryption

[0065] This step utilizes the parameters from step 1) to transform multidimensional data into single data, encrypt and sign it, and send the encrypted data and name to the edge aggregator. At the same time, an additional copy of the signature is sent to the blockchain.

[0066] In the encryption phase of this step, the fault entity, i.e. the smart terminal, uses the super-increment sequence to convert the original multidimensional data into a single data, and then encrypts and signs the converted data.

[0067] 1) Smart terminals will integrate multi-dimensional data m ij Transform into The ciphertext is calculated as shown in Equation 1.2, where T is the timestamp;

[0068]

[0069] 2) The intelligent terminal calculates the auxiliary parameter δ i ID i This is the pseudo-identity of the i-th smart terminal.

[0070]

[0071] and tags i ;

[0072]

[0073] 3) The smart terminals send information {C} respectively. i ,T,δ i , tag i} and {T, δ i , tag i} For edge aggregators and blockchain.

[0074] 3. Data aggregation

[0075] This step utilizes the encrypted data from step 2). The edge aggregator performs weighted aggregation on the encrypted data and also aggregates the signatures before sending them to the cloud control center and the blockchain.

[0076] In the aggregation phase of this step, the edge entity, namely the edge aggregator, aggregates the ciphertext and auxiliary parameters sent by the smart terminal.

[0077] 1) The edge aggregator calculates the aggregated ciphertext C as shown in Equation 1.5;

[0078]

[0079] 2) The edge aggregator randomly selects two integers, nonce and sk. prg ∈SK prgUse the random number generator prag to generate l-1 random numbers prag(sk) prg , nonce)→{π1, π2,...,π l-1}, and set The edge aggregator then calculates two auxiliary parameters, δ and σ, as shown in Equations 1.6 and 1.7.

[0080]

[0081] 3) The edge aggregator sends information {C, T} and {δ, σ, nonce, sk} respectively. prg} For the control center of the cloud layer and the blockchain of the chain layer.

[0082] 4. Data Decryption

[0083] In this step, the cloud control center uses the aggregated data from step 3) to decrypt and obtain a single-dimensional data aggregation value. The blockchain layer uses the aggregated signature value sent from step 3) and the single-dimensional data aggregation value decrypted by the control center to perform signature verification, ensuring data integrity and authenticity.

[0084] In this decryption phase, the control center first uses its own private key to decrypt the aggregated data for each dimension, and then the blockchain verifies the integrity and authenticity of the decrypted data.

[0085] 1) The control center uses the private key ν0 to calculate W, as shown in Equation 1.8.

[0086]

[0087] set up There are (1+N) E =1 + N·E (mod N) 2 Therefore, E = (W-1) / N. Then for each modulus μ j Calculate E divided by μ j The remainder gives the aggregate value m for each dimension of the data. j =E mod μ j .

[0088] 2) Blockchain utilizes a pseudo-random function generator prag(sk) prg , nonce) generates {π1, π2,...,π l-1}, then calculate π l As shown in equation 1.9.

[0089]

[0090] Verify whether equation 1.10 is true. If it is true, it means that the data has been correctly aggregated.

[0091]

[0092] 3) Verified data will be stored in the cloud. When an entity in the access layer has a need, it can query the cloud to obtain the data.

[0093] The superiority of the technical solution of this invention was verified through experiments. Three experiments were conducted, and the experimental results for the computational overhead of the smart terminal, the computational overhead of the edge aggregator, and the blockchain gas consumption are as follows: Figure 1 , 2 As shown in Figure 3.

[0094] Experiment 1 significantly optimizes the computational overhead of the smart terminal. Paillier encryption requires only a single operation to protect data, reducing the additional steps of adding / deleting masks compared to masking schemes. The computation time of the smart terminal increases linearly and slowly with the increase of data dimensionality, rather than exponentially, proving its applicability to performance-constrained IoT terminals.

[0095] Experiment 2 shows that the edge aggregator has high aggregation efficiency and strong scalability. The signature aggregation technology merges the signatures of multiple terminals into a single signature, which greatly reduces the verification overhead. The aggregation time maintains a low slope as the number of terminals increases, proving that the scheme supports efficient aggregation of a large number of terminals.

[0096] Experiment 3 shows that the on-chain verification cost of the blockchain is controllable, and the gas consumption remains almost flat as the number of terminals increases, which is significantly better than the traditional solution of putting every piece of data on the chain.

[0097] like Figure 5 As shown, this embodiment discloses a large-scale distributed intelligent terminal trusted data aggregation system for performing the above method, which includes the following modules:

[0098] Initialization module: Defines public parameters and private parameters for each entity in the access layer;

[0099] Data encryption module: Using the parameters in the initialization module, the smart terminal at the end layer converts multi-dimensional data into single data for encryption and signing, and sends the encrypted data and signature to the edge aggregator at the edge layer, while also sending the signature to the blockchain at the chain layer;

[0100] Data aggregation module: The edge aggregator in the edge layer performs weighted aggregation of the encrypted data in the data encryption module, and also aggregates the signatures and sends them to the control center in the cloud layer and the blockchain in the chain layer.

[0101] Data decryption module: The cloud layer's control center uses the aggregated data in the data aggregation module to decrypt and obtain a single-dimensional data aggregation value. The blockchain in the chain layer uses the aggregated signature value sent by the data aggregation module and the single-dimensional data aggregation value decrypted by the control center to perform signature verification.

[0102] Other aspects of this embodiment can be found in the above method embodiments.

[0103] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A method for large-scale distributed intelligent terminal trusted data aggregation, characterized in that, The specific steps are as follows: Step 1: Initialization, defining public parameters and private parameters for each entity in the access layer; Step 2: Using the parameters from Step 1), the smart terminal at the edge layer converts multi-dimensional data into single data for encryption and signing, and sends the encrypted data and signature to the edge aggregator at the edge layer, while also sending the signature to the blockchain at the chain layer. Step 3: The edge aggregator of the edge layer performs weighted aggregation on the encrypted data of Step 2), and simultaneously aggregates the signatures and sends them to the control center of the cloud layer and the blockchain of the chain layer. Step 4: The cloud layer's control center decrypts the aggregated data from step 3) to obtain a single-dimensional data aggregation value. The blockchain in the chain layer uses the aggregated signature value sent in step 3) and the single-dimensional data aggregation value decrypted by the control center to perform signature verification.

2. The method for large-scale distributed intelligent terminal trusted data aggregation as described in claim 1, characterized in that, In step 1, the public parameters include multiplicative cyclic groups, bilinear pairing maps, Paillier cryptosystems, and super-incrementing sequences, while the private parameters include the entity's private key.

3. The method for large-scale distributed intelligent terminal trusted data aggregation as described in claim 2, characterized in that, Step 1 is as follows: 1) The key generation center is selected from two multiplicative cyclic groups of order p. Set up a group Let g be a generator, and then from the group Randomly select elements θ, sk′, g j 1 ≤ j ≤ k, where j represents the number of dimensions of the terminal data and k represents the maximum number of dimensions of the data, and a bilinear pair mapping is defined. The parameters of the Paillier cryptosystem are set by selecting two large prime numbers {q1, q2} that satisfy gcd(q1q2, (q1-1)(q2-1)) = 1, where gcd is the greatest common divisor; public parameters N = q1q2 and ρ = N+1 are set, along with the system master private key λ = lcm(q1-1, q2-1); four hash functions are defined at the key generation center. and 2) The key generation center is from the integer group The private key ν of the randomly selected smart terminal is used. i i = 1, 2, ..., l, where l represents the maximum number of smart terminals and the public key. And generate the private key for the control center. satisfy And calculate auxiliary parameters The key generation center deploys a pseudo-random number generator. Among them, SK prg It is a set of private keys, and nonce is a random number; 3) The key generation center defines k parameters μ of the super-incrementing sequence. j (1≤j≤k) satisfies equation (1.1), where ξ j It is the maximum value of the j-th dimension data, and μ1 = 1; 4) The key generation center will combine {ν0, sk′} and {v i g j The parameters {N,ρ,g,e,θ,H1,H2,H3,H4,σ} are sent to the control center and the smart terminal respectively, broadcasting common parameters {N,ρ,g,e,θ,H1,H2,H3,H4,σ}. i ,sk',g j ,prg}.

4. The method for large-scale distributed intelligent terminal trusted data aggregation as described in claim 3, characterized in that, Step 2 is as follows: 1) Smart terminals will integrate multi-dimensional data m ij Transform into And calculate the ciphertext C, as shown in equation (1.2), where T is the timestamp, ω i Let be the weight parameters for the i-th smart terminal; 2) The intelligent terminal calculates the auxiliary parameter δ i , of which; ID i For the pseudo identity of the i-th smart terminal, and tags i ; 3) The smart terminals send information {C} respectively. i ,T,δ i , tag i } and {T, δ i , tag i } For edge aggregators and blockchain.

5. The method for large-scale distributed intelligent terminal trusted data aggregation as described in claim 4, characterized in that, Step 3 is as follows: 1) The edge aggregator calculates the aggregated ciphertext C, as shown in equation (1.5). 2) The edge aggregator randomly selects two integers, nonce and sk. prg ∈SK prg Use the random number generator prag to generate l-1 random numbers prag(sk) prg , nonce)→{π1, π2,...,π l-1 }, and set Then the edge aggregator calculates two auxiliary parameters δ and σ, as shown in equations (1.6) and (1.7); 3) The edge aggregator sends information {C, T} and {δ, σ, nonce, sk} respectively. prg } For the control center of the cloud layer and the blockchain of the chain layer.

6. The method for large-scale distributed intelligent terminal trusted data aggregation as described in claim 5, characterized in that, Step 4 is as follows: 1) The control center uses the private key v0 to calculate W, as shown in equation (1.8); set up There are (1+N) E =1 + N·E (mod N) 2 Therefore, E = (W-1) / N; then for each modulus μ j Calculate E divided by μ j The remainder gives the aggregated value m of each dimension of the data. j =E modμ j ; 2) Blockchain utilizes a pseudo-random function generator prag(sk) prg , nonce) generates {π1, π2,...,π l-1 }, then calculate π l As shown in equation (1.9); Verify whether equation (1.10) holds true. If it does, it means that the data has been correctly aggregated.

7. A large-scale distributed intelligent terminal trusted data aggregation system, used to perform the method as described in any one of claims 1-6, characterized in that, Includes the following modules: Initialization module: Defines public parameters and private parameters for each entity in the access layer; Data encryption module: Using the parameters in the initialization module, the smart terminal at the end layer converts multi-dimensional data into single data for encryption and signing, and sends the encrypted data and signature to the edge aggregator at the edge layer, while also sending the signature to the blockchain at the chain layer; Data aggregation module: The edge aggregator in the edge layer performs weighted aggregation of the encrypted data in the data encryption module, and also aggregates the signatures and sends them to the control center in the cloud layer and the blockchain in the chain layer. Data decryption module: The cloud layer's control center uses the aggregated data in the data aggregation module to decrypt and obtain a single-dimensional data aggregation value. The blockchain in the chain layer uses the aggregated signature value sent by the data aggregation module and the single-dimensional data aggregation value decrypted by the control center to perform signature verification.

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