CN116318901A - Privacy and verifiable internet of things data aggregation method integrating blockchain - Google Patents

Privacy and verifiable internet of things data aggregation method integrating blockchain Download PDF

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CN116318901A
CN116318901A CN202310163828.8A CN202310163828A CN116318901A CN 116318901 A CN116318901 A CN 116318901A CN 202310163828 A CN202310163828 A CN 202310163828A CN 116318901 A CN116318901 A CN 116318901A
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data
promise
cloud server
internet
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黄志清
高月
何俊
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Beijing University of Technology
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L63/00Network architectures or network communication protocols for network security
    • H04L63/04Network architectures or network communication protocols for network security for providing a confidential data exchange among entities communicating through data packet networks
    • H04L63/0428Network architectures or network communication protocols for network security for providing a confidential data exchange among entities communicating through data packet networks wherein the data content is protected, e.g. by encrypting or encapsulating the payload
    • H04L63/0442Network architectures or network communication protocols for network security for providing a confidential data exchange among entities communicating through data packet networks wherein the data content is protected, e.g. by encrypting or encapsulating the payload wherein the sending and receiving network entities apply asymmetric encryption, i.e. different keys for encryption and decryption
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L63/00Network architectures or network communication protocols for network security
    • H04L63/12Applying verification of the received information
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L67/00Network arrangements or protocols for supporting network services or applications
    • H04L67/01Protocols
    • H04L67/10Protocols in which an application is distributed across nodes in the network
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L67/00Network arrangements or protocols for supporting network services or applications
    • H04L67/01Protocols
    • H04L67/12Protocols specially adapted for proprietary or special-purpose networking environments, e.g. medical networks, sensor networks, networks in vehicles or remote metering networks
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L9/00Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
    • H04L9/008Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols involving homomorphic encryption

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Abstract

The invention discloses a privacy and verifiable internet of things data aggregation method fusing blockchains, and belongs to the fields of privacy protection and data aggregation. The method adopts homomorphic encryption technology to encrypt and transmit multiparty Internet of things data participating in aggregation to the cloud server, and the cloud server aggregates the multiparty Internet of things data on the basis of ciphertext, so that the privacy of the data in the calculation process is effectively protected. And generating a promise for the ciphertext data uploaded to the cloud server by adopting a promise mechanism, wherein the promise is used for verifying the consistency of the data and the correctness of the aggregation result. In addition, the block chain and the intelligent contract are utilized to carry out the evidence storage on the promise, so that the verification of the evidence storage on the chain of the data is realized, the verifiability of the calculation process is ensured, and the cloud server is effectively supervised. The method solves the problems of data privacy and verifiability in the data aggregation process in the field of the Internet of things by adopting homomorphic encryption technology and a promise mechanism and fusing a blockchain technology. The intelligent network system can be widely applied to various intelligent application scenes of the Internet of things, such as intelligent power grids, intelligent medical treatment and the like.

Description

Privacy and verifiable internet of things data aggregation method integrating blockchain
Technical Field
The invention relates to the field of data aggregation of the Internet of things, a blockchain technology and a homomorphic encryption technology, and discloses a data aggregation privacy protection and verifiable method based on blockchain and homomorphic encryption design in the scene of the Internet of things.
Background
The internet of things technology rapidly develops to become one of the most important technologies at present, and a great deal of research is currently carried out on related applications of the internet of things technology, such as smart power grids, smart medical treatment, internet of vehicles and the like, and the applications need to collect and aggregate data from different enterprises or individuals to carry out learning analysis so as to find specific rules or characteristics of the data, for example, in the field of smart power grids, the analysis of the electricity consumption of users in a certain area can help a power supply bureau to reasonably distribute the electricity, so that resource waste is avoided; in the medical field, the function of data aggregation is to collect and analyze relevant body data of patients to help to acquire body health indexes, so as to achieve the function of preventing and timely treating. The internet of things system collects sensitive data, such as patient privacy data, business data and the like, and the data are usually transmitted and stored on a cloud server, data storage, management and analysis are gradually transferred to a third party cloud server, the security privacy of the internet of things data also depends on the cloud, but the cloud server may have a significant security problem: (1) During the calculation and storage process, data leakage may be caused by active or passive reasons, such as configuration errors, malicious attackers, etc.; (2) The lack of supervision on the cloud server cannot guarantee the correctness of the cloud computing process and result. Therefore, in the data aggregation process of the Internet of things based on the cloud server, the data privacy is protected, and the data accuracy is guaranteed.
At present, a great deal of research is also conducted on the privacy protection of the data aggregation of the internet of things under the cloud, and most of the research adopts a cryptographic encryption mode, such as asymmetric encryption, homomorphic encryption and the like. Homomorphic encryption is a cryptographic algorithm, can directly calculate on ciphertext without decryption, is equivalent to directly calculating plaintext, can protect privacy and security of data in an untrusted or semi-trusted third party cloud due to homomorphic characteristics, and is a feasible solution widely applied. The homomorphic encryption cannot provide verification of consistency and correctness of data, the promise mechanism is an important prototype of cryptography, and remote fair game can be carried out under the condition that no third party exists, so that the unique promise of the data generated by adopting the promise mechanism can supervise the calculation process of the third party cloud server, and verification of consistency and result correctness of the data is realized. The blockchain is used as an anti-tampering, traceable and shared account book technology, has the characteristics of decentralization, programmability, safety, credibility and the like, is also a distributed network data management technology, is commonly used for storing key data, and uploads promise to the blockchain as evidence by a fusion blockchain technology to store the promise, so that the verifiability of the data is realized.
Disclosure of Invention
The invention mainly aims to provide a data aggregation method of a fusion blockchain and a verifiable internet of things, which expands the original method for protecting privacy in data aggregation by using homomorphic encryption into the verification of the data range on the basis of protecting the data privacy by combining homomorphic encryption with zero knowledge proof and realizes the verification of the calculation correctness of the data by combining a blockchain and a commitment mechanism. The system model diagram is shown in fig. 1.
In order to achieve the purpose of the invention, the technical scheme adopted by the invention is as follows: a privacy and verifiable internet of things data aggregation method integrating blockchain mainly comprises the following roles:
(1) A data provider;
the data provider can be sensor equipment such as a wireless sensor network in the Internet of things, or mobile equipment such as an acquisition robot, has sensing and communication functions, for example, the data provider can be an intelligent ammeter in an intelligent power grid, and meanwhile, the data provider also comprises an edge server (or gateway), and the data is uniformly transmitted to the edge server for data processing due to weak computing capacity of the sensor and other equipment. The main task of the data provider is to collect data and perform preprocessing operation on the data, the collected data belongs to original data, and the data is assumed to be a dishonest participant and possibly forged or modified, so that the purpose of influencing the final aggregation result is achieved by encrypting invalid data.
(2) A cloud server;
and a third party cloud server with high computing and high storage capacity. The main task is to verify and aggregate data from a data provider, and the data cannot be actively leaked or counterfeited under the assumption that the data is a semi-honest participant, but the data can be leaked due to the attack of an external node or unexpected faults occur inside the data, so that a calculation error can obtain an error analysis result.
(3) A data user;
the owners and users of the data may be power centers in smart grids, hospitals in smart medicine, or any other institution or individual. The data user designates an aggregation scheme, the final calculation result of the cloud server can be returned to the data user, and the final calculation result is the owner of the final aggregation data plaintext, is assumed to be a trusted participant, is a completely trusted party in the system, and does not perform any fraudulent or passive leakage behavior.
(4) A blockchain;
as a distributed account book technology, the cloud server is mainly used for storing and assisting the cloud server in verifying data in the structure. Compared with public chains and private chains, the alliance chains are more suitable for the scene of the model.
Further, the implementation method of the privacy and verifiable internet of things data aggregation method fusing blockchains is as follows:
(1) And (3) initializing. Generating public key PK of homomorphic algorithm aiming at homomorphic encryption algorithm, promise mechanism and the like which are needed to be used in privacy protection scheme pai、 Private key SK pai Initializing a commitment mechanism, generating related parameters, and uploading the related parameters and the public key to the blockchain.
(2) And a data acquisition and preprocessing stage. The related internet of things equipment performs real-time data acquisition (such as data acquisition every 15 minutes), performs related preprocessing operation on the data in real time, and firstly uses the homomorphic public key PK pai The data is encrypted to obtain a ciphertext, and in order to protect the privacy security of the data, the subsequent processing is performed based on the ciphertext, and the process is shown as (1) in fig. 1. The subsequent processing is divided into two steps, first generating a commitment to ciphertext based on the random value, as in (2) of FIG. 1As shown. And after the data processing is completed, data transmission is carried out, the promise is uploaded to a block chain, and then ciphertext is transmitted to a calculation server.
(3) And a data aggregation stage. After receiving the related data, the computing server firstly acquires the promise of the data from the blockchain, and verifies the promise obtained by the local computing and the acquired promise to be consistent, and if the promise is consistent, the data is also consistent, and the process is shown as (3) in fig. 1. After the verification is finished, the correctness and consistency of the data are ensured, all the data passing the verification are calculated to obtain a calculation result, and the process is shown as (4) in fig. 1.
(4) And (3) a verification stage. Since the calculation is homomorphic calculation, the calculation result is ciphertext, the correctness of the result is verified by utilizing the promised multiplication homomorphism before decryption, and after the calculation result is verified to be correct, the decryption can be performed to return the result, and the process is shown as (5) in fig. 1.
Further, the promise mechanism and the blockchain are combined to carry out data verification, promise of original ciphertext data is generated through the promise mechanism and stored in the blockchain, the promise mechanism with homomorphic characteristics is adopted, the consistency of the data can be verified, and meanwhile, the final aggregation calculation result can be verified, wherein the two verifications are that after ciphertext data are received by a cloud server, the promise is utilized to verify, and the data are guaranteed not to be tampered in the middle; after the cloud server performs data aggregation, the cloud server is ensured to correctly execute the calculation tasks, the cloud execution aggregation is monitored, and the final ciphertext result is verified to be correct.
Compared with the existing data sharing model and management and control method of the Internet of things, the privacy and verifiable data aggregation method of the Internet of things integrating the blockchain has the following advantages:
compared with the traditional data aggregation privacy protection method, the method has the advantages that non-interactive zero knowledge proof is combined on the homomorphic encryption basis, so that data counterfeiting by participants is effectively prevented, the data privacy protection in the whole aggregation process is performed, the data correctness and consistency are ensured, and the data pollution attack by the participants is effectively weakened.
The invention introduces the blockchain technology and the promise scheme to carry out the certification on the basis of privacy protection, the blockchain stores the related promise of the data into the blockchain for carrying out the calculation correctness verification due to the non-tamper characteristic, and provides a true and effective certificate for the verification due to the public transparent characteristic of the blockchain, thus not only carrying out straightness verification on the uploaded data, but also carrying out the correctness verification on the calculation result.
The universal model provided by the invention is applicable to the Internet of things scene with privacy protection requirements, so that the universal model has wide applicability.
Drawings
Fig. 1 is a system model diagram of a data aggregation method of a privacy and verifiable internet of things integrating blockchains according to an embodiment of the invention.
Fig. 2 is a flowchart of an implementation of a method for aggregating privacy and verifiable internet of things data by fusing blockchains according to an embodiment of the present invention.
Fig. 3 is a timing diagram of a data aggregation method of the internet of things integrating privacy and verifiable of blockchain according to an embodiment of the present invention.
Detailed Description
For the purpose of making the present invention more clear and defining the invention, so as to facilitate the understanding of the present invention by those skilled in the art, the following further details of the present invention will be described with reference to fig. 3, and the specific steps of the embodiment are as follows:
(1) And a system initialization stage.
The data user deploys intelligent contracts aiming at the required tasks to carry out subsequent calculation verification, wherein the homomorphic encryption algorithm adopts the Paillier algorithm, the promise mechanism is constructed based on the RSA algorithm, and the Paillier homomorphic key pairs sk and pk, random prime numbers e and maximum order elements g required by the promise scheme are generated according to the key generation algorithm m Public keys pk, e, g m Distributed to the data provider, the private key sk is uploaded into the smart contract. Here RSA multiplication homomorphic commitment schemeThe Paillier homomorphism algorithm uses the same N as its common commitment modulus and encryption modulus.
(2) And a data acquisition stage.
The terminal device performs real-time data acquisition (here we assume two data providers DP i And DP j To illustrate by performing data collection work), the data is locally preprocessed, i.e. the original data m is preprocessed using the homomorphic public key pk i ,m j Encryption is carried out to obtain homomorphic ciphertext
Figure BDA0004095174490000041
The homomorphic encryption can also ensure the security of the data in the transmission process to a certain extent, and simultaneously, the promise scheme is used for generating promise of ciphertext data
Figure BDA0004095174490000042
Uploading to a blockchain to become a unique unalterable credential for public auditing, ciphertext ++>
Figure BDA0004095174490000051
And transmitting the cloud server and the cloud server together.
(3) And a data aggregation stage.
The cloud server receives the data and performs aggregation (in this embodiment, addition calculation is taken as an example, and aggregation may also be calculation such as averaging, maximum value, minimum value, etc.), that is, calculation
Figure BDA0004095174490000052
For all data P, the data calculation is performed as:
Figure BDA0004095174490000053
due to homomorphism, the cloud can directly calculate on the ciphertext to obtain target data, the privacy of the data is ensured, external attack is prevented, and the random value promised is added sum =r i +r j The same applies to all data PThe data calculation is as follows:
Figure BDA0004095174490000054
after the calculation is completed, the aggregated ciphertext data Pai sum Sum of random values and r sum A common stream is uploaded into the blockchain for subsequent verification of the results.
(4) And a data decryption stage.
Upon receipt of the aggregated data Pai sum The intelligent contract automatically performs calculation correctness verification, and when the aggregation is completed, ciphertext data Pai uploaded by the cloud server is received sum Sum of random values and r sum The promise can be opened to verify the correctness of the data result, and the specific verification is as follows according to the homomorphic characteristic of the promise proposed by us:
Figure BDA0004095174490000055
the verification method is applied to all data as follows:
Figure BDA0004095174490000061
therefore, the multiplication characteristic of RSA multiplication homomorphic promise scheme can be combined with the addition characteristic of Paillier algorithm, according to the sum r of random values sum Verification is carried out, after the audit is passed, the private key sk is directly used for decrypting the data to obtain the aggregated plaintext number sum=dec (Pai sum ) And returning a final result to the data provider, and if the audit is not passed, returning error information.
The method is based on the characteristic that homomorphic encryption can directly calculate ciphertext, and the characteristics of block chain tamper resistance, traceability, safety, reliability and the like, and provides the data aggregation privacy protection method of the Internet of things based on the block chain and homomorphic encryption, so that privacy protection and verification in the data aggregation process are realized. The invention can realize privacy protection of data in the whole process based on the alliance chain and Paillier homomorphism algorithm, and can realize that a task demand party obtains a data aggregation result to make a corresponding decision under the condition of not obtaining specific data.

Claims (2)

1. A privacy and verifiable internet of things data aggregation method integrating blockchain is characterized in that: the system architecture implementing the method includes the following roles,
(1) A data provider;
the data provider is wireless sensor network sensor equipment in the Internet of things or acquisition robot mobile equipment, has sensing and communication functions, and also comprises an edge server or gateway; uniformly transmitting the data to an edge server, and processing the data; the task of the data provider is to collect data and perform preprocessing operation on the data, the collected data belongs to original data, if the collected data is dishonest, the data can be forged or modified, and the aim of influencing a final aggregation result is achieved by encrypting invalid data;
(2) A cloud server;
the cloud server is a third party cloud server with high computing and high storage capacity; the task is to verify and aggregate the data from the data provider, if the data is a semi-honest participant, the data cannot be actively leaked or counterfeited, but the data can be leaked by the attack of an external node or unexpected faults occur in the data provider, so that a calculation error can obtain an error analysis result;
(3) A data user;
owners and users of data, in smart grids, power centers, hospitals in smart medicine, or any other institution or individual; the data user designates an aggregation scheme, the final calculation result of the cloud server is returned to the data user, and the data user is an owner of a final aggregate data plaintext, is assumed to be a trusted participant, is a complete trusted party in the system, and does not perform any fraudulent or passive leakage behavior;
(4) A blockchain;
the distributed account book technology is used for storing, and the auxiliary cloud server verifies the data; comparing public chains with private chains, the alliance chains are more suitable for the scene of the model;
the implementation method is as follows,
(1) An initialization stage; aiming at homomorphic encryption algorithm and promise mechanism which are needed to be used in privacy protection scheme, public key PK of homomorphic algorithm is generated pai Private key SK pai Initializing a commitment mechanism, generating related parameters, and uploading the related parameters and the public key to a blockchain;
(2) Data acquisition and preprocessing; the related internet of things equipment performs real-time data acquisition and performs related preprocessing operation on the data in real time, and firstly uses homomorphic public key PK pai Encrypting the data to obtain a ciphertext, and carrying out subsequent processing on the basis of the ciphertext in order to protect the privacy security of the data; the subsequent processing is divided into two steps, firstly, generating a promise of ciphertext according to a random value; after finishing the data processing, carrying out data transmission, firstly uploading promise to a block chain, and then transmitting ciphertext to a calculation server;
(3) A data aggregation stage; after receiving the related data, the computing server firstly acquires the promise of the data from the blockchain, and performs consistency verification on the promise obtained by the local computing and the acquired promise, wherein the promise is consistent, and the data is also consistent; after verification is completed, the correctness and consistency of the data are ensured, and all the data passing the verification are calculated to obtain a calculation result;
(4) A verification stage; because the calculation is homomorphic calculation, the calculation result is ciphertext, the correctness of the result is verified by utilizing the promised multiplication homomorphism before decryption, and the result can be decrypted and returned after the calculation result is verified to be correct.
2. The method for aggregating data by combining privacy and verifiable Internet of things of a blockchain according to claim 1, wherein the method is characterized in that the data is verified by combining a commitment mechanism and the blockchain, commitment of original ciphertext data is generated through the commitment mechanism and stored in the blockchain, and the commitment mechanism with homomorphic characteristics is adopted to verify not only consistency of the data, but also final aggregate calculation results, wherein the two verifications are that after ciphertext data is received by a cloud server, the cloud server verifies by utilizing commitment before aggregation, and the data is ensured not to be tampered in the middle; after the cloud server performs data aggregation, the cloud server is ensured to correctly execute the calculation tasks, the cloud execution aggregation is monitored, and the final ciphertext result is verified to be correct.
CN202310163828.8A 2023-02-24 2023-02-24 Privacy and verifiable internet of things data aggregation method integrating blockchain Pending CN116318901A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116827821A (en) * 2023-07-03 2023-09-29 北方工业大学 Block chain cloud-based application program performance monitoring model and method

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116827821A (en) * 2023-07-03 2023-09-29 北方工业大学 Block chain cloud-based application program performance monitoring model and method
CN116827821B (en) * 2023-07-03 2024-04-30 北方工业大学 Block chain cloud-based application program performance monitoring method

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