Provable Data Possession Scheme Research Articles

Enabling Integrity and Compliance Auditing in Blockchain-Based GDPR-Compliant Data Management

The General Data Protection Regulation (GDPR) is a European Union (EU) data protection and privacy law. According to the GDPR, the data on a hosting platform must meet semantic consistency and data integrity requirements. Semantic consistency means that the data operation should comply with the GDPR, while data integrity is meant to ensure that the outsourcing data should be intact. The two terms are not interchangeable. For example, if a cloud service provider migrates data to foreign storage nodes without authorization of the data owner, the data integrity requirement of the GDPR is met but the semantic consistency requirement is not. How to ensure data integrity and compliance is the main challenge for a GDPR-compliant data supervision platform. To achieve this aim, we leverage a blockchain based data management framework to check the data compliance, which can break the black box of the data hosting platform and demonstrate its logic to data owners, allowing for inspection. We propose a new provable data possession (PDP) scheme for the aforementioned framework that can check for semantic consistency and data integrity simultaneously. The verifier does not need to hold any audited data, which can reduce bandwidth usage. The verification result can be regarded as the proof for subsequent data recovery and accountability. Experimental results show higher efficiency of the PDP scheme.

Certificateless Provable Data Possession Scheme With Provable Security in the Standard Model Suitable for Cloud Storage

Certificateless Provable Data Possession Scheme With Provable Security in the Standard Model Suitable for Cloud Storage

Certificateless Provable Data Possession Scheme Suitable for Smart Grid Management Systems

A large amount of data are generated at each section of the smart grid. Safely and efficiently storing and managing this data is a crucial challenge faced by the smart grid. Cloud-based smart grid management system (CB-SGMS) is a great choice for addressing this problem. Various departments in the smart grid upload the collected data to the cloud for storage. Due to the lack of physical control over the data stored in the cloud, it is a significant issue to judge that the data are intact. Provable data possession (PDP) scheme can solve this problem. Each department sends data to the cloud and entrusts it to a third-party verifier (TPV) to conduct integrity checks on data. In 2018, He et al. put forward a certificateless provable data possession (CL-PDP) scheme for CB-SGMS and professed that their scheme is secure. Unfortunately, we pointed out that there are security flaws in the scheme by showing two concrete attacks. We then came up with an improved scheme to make up for the security flaws. We presented the security requirements and gave the security proofs based on the discrete logarithm problem. In the end, we execute a comparison on performance for the improved scheme and the other five schemes. The results show that the improved scheme is more secure and efficient than other ones, which makes it suitable for CB-SGMS.

A collusion-resistant certificateless provable data possession scheme for shared data with user revocation

A collusion-resistant certificateless provable data possession scheme for shared data with user revocation

Post-Quantum Privacy-Preserving Provable Data Possession Scheme Based on Smart Contracts

Provable data possession (PDP) is a crucial means of protecting the integrity of data in the domain of cloud storage. In the post-quantum era, the PDP scheme that uses lattices relies too heavily on the third-party auditor (TPA), which is not entirely trustworthy and is easily affected by a single point of failure. Moreover, the scheme often leads to the leakage of private user data while attempting to satisfy the demand for public verification. In response to the above problems, this paper designs a protocol for post-quantum privacy-preserving PDP and uses it to develop a scheme based on smart contracts. The proposed scheme has the characteristics of being post quantum and can satisfy the demand for public verification while preserving user privacy. The property of noninteraction of the protocol can reduce transaction fees incurred owing to the frequent operation of the blockchain, and the smart contract with a deposit mechanism can ensure fair payments to all parties. The results of a theoretical analysis and experiments show that the proposed scheme is highly secure and efficient.

SChain: An Efficient and Secure Solution for Improving Blockchain Storage

Emerging blockchain technology has become the cornerstone of many applications providing trusted data services. However, existing blockchain platforms cannot meet the growing demand for big data storage. Blockchain should duplicate both transactions and other user-defined data across nodes for integrity assurance. The rapid expansion of data on blockchain (on-chain data) increases the difficulty of deploying a full node, resulting in decreasing the degree of decentralization and adding the risk of broken data. To tackle these problems, we propose sChain, a novel framework for improving blockchain storage capacity, which does not revise blockchain implementation and can be applied to almost all the existing blockchain platforms. sChain outsources the user data to storage devices that are structurally external to the blockchain network. In theory, a user can outsource unlimited data to sChain. However, those off-chain data may suffer from corruption. To verify the data integrity, we propose a new provable data possession (PDP) scheme, which does not need a centralized entity to maintain any secret keys and therefore eliminates a single point of failure. What is more, we also design a prototype to accelerate the proposed PDP scheme through Intel SGX technology and parallel processing. Security analysis and evaluation results show that sChain can protect data security and effectively improve the blockchain storage capacity, respectively.

Blockchain-Based Privacy-Preserving Public Auditing for Group Shared Data

Cloud storage has been widely used to team work or cooperation development. Data owners set up groups, generating and uploading their data to cloud storage, while other users in the groups download and make use of it, which is called group data sharing. As all kinds of cloud service, data group sharing also suffers from hardware/software failures and human errors. Provable Data Possession (PDP) schemes are proposed to check the integrity of data stored in cloud without downloading. However, there are still some unmet needs lying in auditing group shared data. Researchers propose four issues necessary for a secure group shared data auditing: public verification, identity privacy, collusion attack resistance and traceability. However, none of the published work has succeeded in achieving all of these properties so far. In this paper, we propose a novel blockchain-based ring signature PDP scheme for group shared data, with an instance deployed on a cloud server. We design a linkable ring signature method called Linkable Homomorphic Authenticable Ring Signature (LHARS) to implement public anonymous auditing for group data. We also build smart contracts to resist collusion attack in group auditing. The security analysis and performance evaluation prove that our scheme is both secure and efficient.

A Certificateless Provable Data Possession Scheme for Cloud-Based EHRs

Electronic health records (EHRs: digital collections of patient health status and diagnosis) are generally shared, analyzed and stored on cloud servers. One operational challenge is to ensure that EHRs are stored correctly, for example using provable data possession (PDP). Seeking to contribute to the literature, we propose a certificateless PDP scheme for cloud-based EHRs. In our scheme, we distribute multiple copies of EHRs on different cloud servers to allow for corrupted EHRs to be recoverable from other intact copies. The scheme is also designed to resist copy-summation attack which assures that cloud servers are storing EHRs honestly. In our approach, EHRs are stored in ciphertext form so that only authorized users can decrypt and gain access to the information. We also design a new data structure – map version marker table (MVMT) – for block-level dynamic operations and data traceability. Specifically, MVMT allows an authorized doctor to access historical EHRs to inform their diagnosis and decision-making. The security and performance analyses show that our scheme is secure (assuming the intractability of the computational Diffie-Hellman problem) and is practical to support cloud-based EHR applications.

Improved Efficient Privacy-Preserving Certificateless Provable Data Possession Scheme for Cloud Storage

Cloud storage technology is evolving at a high speed; effectively auditing the cloud data’s integrity has become a focal point. Recently, Ming and Shi proposed a certificateless integrity auditing scheme with a privacy protection function. The scheme used the certificateless cryptosystem to solve the certificate management problem of the auditing schemes based on public key infrastructure and the key escrow problem of the identity-based auditing schemes. Although their scheme is novel and efficient, we found that their scheme was not secure and could not achieve integrity auditing of cloud data. The malicious cloud server can generate the proof through the blocks and tags sent by the user. On the basis of the original scheme, we propose an improved auditing scheme; our new scheme is more secure and effective. In addition, for the problem of idle tags in the existing cloud data integrity auditing scheme, we propose the idea of intermediate tags and we applied the idea to the improved scheme to improve audit efficiency.

Multicopy and Multiserver Provable Data Possession for Cloud-Based IoT

Provable data possession (PDP) is widely considered to be an efficient method in verifying the integrity of remote data. While earlier PDP schemes are generally designed to check the integrity of data copies on a single cloud server (CS), there have been attempts to design multicopy and multiserver PDP (MCMS-PDP) schemes in recent years. However, it is known that MCMS-PDP schemes may be vulnerable to copy-summation attacks or do not support dynamic operations. The former enables a (dishonest) CS to only store a summation of copies for successful verification, while the latter does not allow the data owner to update the stored data. In this article, we propose a new MCMS-PDP scheme based on homomorphic verifiable tags. Specifically, our proposed scheme is designed to check the integrity of all copies in one challenge–response and resist copy-summation attacks. The scheme also supports public verification and block-level dynamic operations, such as modification, insertion, and deletion using the divide-and-conquer table. We then prove the security of our scheme, assuming the intractability of the computational Diffie–Hellman problem, in the random oracle model. We also evaluate the performance of the scheme to demonstrate its efficiency.

Blockchain-Based Self-Auditing Scheme with Batch Verification for Decentralized Storage

Data owners outsource their data to remote storage providers without keeping local replicas to save their precious storage resources. However, the ownership and management of data are separated after outsourcing. How to ensure the integrity and recoverability of outsourced data becomes a significant problem. Provable Data Possession (PDP) and Proofs of Retrievability (POR) are two cryptographic protocols that enable users to verify the integrity of outsourced data. Nevertheless, the state-of-the-art PDP and POR schemes either need users to perform the complicated audit tasks by themselves or delegate these tasks to a Third-Party Auditor (TPA). Moreover, these schemes are constructed on a centralized storage framework which vulnerably suffers single-point-of-failure. In this paper, we propose a blockchain-based decentralized self-auditing scheme with batch verification. Firstly, data owners outsource their data to decentralized storage nodes, which can achieve self-auditing based on blockchain without TPA. Secondly, our scheme uses Pedersen-based polynomial commitment to significantly reduce the number of authenticators. Furthermore, we propose a batch verification algorithm, which can verify multiple proofs from different storage nodes to improve the verification efficiency. Finally, we analyze the security of our scheme and implement a gas-efficient system prototype using the smart contracts of the Ethereum Reposten test network. The results demonstrate that the scheme is practical.

A Noninteractive Multireplica Provable Data Possession Scheme Based on Smart Contract

With the explosive growth of data, cloud storage has become a widely used storage method. To protect the integrity and availability of data in cloud storage systems, multireplica provable data possession has gradually become a research hotspot. This paper uses smart contracts to replace traditional third-party auditor (TPA) and proposes a noninteractive multireplica provable data possession scheme based on smart contracts, making the verification process public, immutable, traceable, and able to be carried out periodically and automatically. This paper introduces the concept of noninteractivity to reduce the transaction fees caused by the frequent operation of blockchain in the verification process. By stipulating payment rules in the smart contract, we can ensure the fairness of all parties. Finally, we give the correctness proof of the scheme and the security proof in the random oracle model, comparing it with other schemes and verifying the practicability of our scheme through experiments.

Lattice-based provable data possession in the standard model for cloud-based smart grid data management systems

The smart grid is considered to be the next-generation electric power network. In a smart grid, there are massive data to be processed, so cloud computing is introduced into it to form a cloud-based smart grid data management system. However, with data no longer being stored locally, how to ensure the integrity of data stored in the cloud in the smart grid has become an urgent problem awaiting solution. Provable data possession has been proposed to solve this problem. With the development of quantum computer technology, quantum attacks-resistant cryptographic schemes are gradually entering people’s horizons. Lattice cryptography can resist quantum attacks. In this article, a lattice-based provable data possession scheme is proposed for cloud-based smart grid data management systems. The scheme is proved unforgeable under the small integer solution hard assumption in the standard model. Compared with other two efficient lattice-based provable data possession schemes in the standard model, our scheme also shows efficiency.

Accountable outsourcing data storage atop blockchain

Outsourcing data integrity auditing enables users to efficiently check whether their cloud data are stored intactly without retrieving them. However, a problem arises that how to hold the storage server accountable when the auditing results show that the data has been lost or tampered with. In this paper, we propose a blockchain-based accountable data outsourcing storage protocol, which enables users to obtain fine-grained compensation based on the damage of data. We provide an accurate and verifiable damage assessment method to achieve quantitative compensation. Specifically, the damage is assessed by the server and verified by smart contract. Furthermore, our protocol ensures the fairness of participants by deposit mechanism and smart contract. If any participant behaves dishonestly, it cannot obtain any benefit or even be punished. To reduce user’s overhead, we propose a new provable data possession scheme, PDP in short, supporting outsourcing the calculation of tags. Moreover, we provide a detailed security proof for the proposed protocol as well. Finally, we evaluate the time cost of off-chain functions and the gas cost of on-chain operations for our protocol, which demonstrates that it is practical and suitable in reality.

Blockchain-Based Light-Weighted Provable Data Possession for Low Performance Devices

Provable Data Possession (PDP) schemes have long been proposed to solve problem of how to check the integrity of data stored in cloud service without downloading. However, with the emerging of network consisting of low performance devices such as Internet of Things, we find that there are still two obstacles for applying PDP schemes. The first one is the heavy computation overhead in generating tags for data blocks, which is essential for setting up any PDP scheme. The other one is how to resist collusion attacks from third party auditors with any possible entities participating the auditing. In this paper, we propose a novel blockchain-based light-weighted PDP scheme for low performance devices, with an instance deployed on a cloud server. We design a secure outsourced tag generating method for low performance devices, which enables a kind of “hash-sign-switch” two-phase tag computing. With this method, users with low performance devices can employ third party auditors to compute modular exponential operations that accounts for the largest portion of computation overhead in tag generation, without leaking their data content. Chaincodes in blockchain network ensure the correctness of such outsourcing and prevent collusion attacks. The security analysis and performance evaluation prove that our scheme is both secure and efficient.

Towards Lightweight Provable Data Possession for Cloud Storage Using Indistinguishability Obfuscation

Cloud Computing has proved to be a boon for many individuals and organizations who cannot afford infrastructure and maintenance cost of resources. But the untrusted nature of Cloud Server (CS) brings many challenges related to security and trust. Public auditing is one process that enables users to delegate the integrity verification of outsourced data to external party such as Third-Party Auditor (TPA). Provable Data Possession (PDP) is one approach of auditing that can verify the integrity using cryptographic algorithms. Many PDP schemes are based on bilinear pairing and homomorphic authenticators that involves complex computations that leads to increased verification time. The lightweight auditing processes is a need today using modern cryptographic techniques. Indistinguishability Obfuscation (IO) is one of the modern but weaker primitive that, if used with one-way functions, provide multiple cryptographic constructs. Sahai and Waters proposed construction of cryptographic constructs using IO. Zhang <i>et al.</i> proposed lightweight public auditing scheme using these IO. But still there are many goals to achieve such as group support, collusion handling, privacy-preserving etc. using IO. In this paper, we are trying to explore these issues and lists future research directions in this field.

Blockchain Assisted Multi-Copy Provable Data Possession With Faults Localization in Multi-Cloud Storage

Cloud storage service provides a convenient way for users to store massive data. To guarantee the integrity of the outsourced data, provable data possession (PDP) schemes for multi-copy data and multi-cloud have been proposed respectively. To avoid a single point of failure and to increase the security of the outsourced data, many users store multiple copies on multiple cloud servers. However, few protocols support multi-copy data and multi-cloud at the same time. Considering that three entities (third-party auditor, cloud organizer and cloud storage servers) participate in the auditing process, it is difficult for users to locate the position of the faults, including entity position, file position and data block corruption position, when the auditor reports data corruption. In this paper we propose a certificateless multi-copy public auditing protocol in multi-cloud storage, which supports to locate the faults entities and corrupted data blocks. Specifically, instead of relying on a trusted centralized judgement entity to deal with the faults detection, smart contracts combined with the binary search technique are utilized to help achieve the reliability of faults localization result and the accuracy of the judgement. Additionally, the proposed protocol supports data dynamics update, including data modification, insertion and deletion. Theoretical analysis and experiment results show that our protocol is efficient and practical.

Synchronized Provable Data Possession Based on Blockchain for Digital Twin

In the digital twin environment, the fusion data onto physical entities in the physical space are mapped to multiple virtual spaces for digital modeling and intelligent simulation in different dimensions. In real intelligent manufacturing scenarios, heterogeneous multi-source fusion data are collected at the same time period. So they are consistent in time state. For the autonomous digital twin system, time states verification and integrity checking are basic security factors. Provable data possession technology can check the integrity of data onto virtual spaces. The blockchain can provide the synchronization interface to make distributed entities to obtain the trusted time state value. Considering the privacy, the blockchain can also provide anonymous services for entities. Therefore, we propose the blockchain-based synchronized provable data possession scheme (named BSPDP) for digital twin. In our scheme, the selection of verifier is flexible. Since virtual spaces may be maliciously framed to pay compensation, we use tag verification to prevent honest virtual spaces from being framed. Under the assumption of RSA, the proposed BSPDP is provably secure. Finally, the performance analysis demonstrates that BSPDP is practical. The experimental results show that BSPDP is effective and attractive for digital twin.

Efficient Identity-Based Provable Multi-Copy Data Possession in Multi-Cloud Storage

To increase the availability and durability of the outsourced data, many customers store multiple copies on multiple cloud servers. To guarantee the integrity of multi-copies, some provable data possession (PDP) protocols for multi-copy are presented. However, most of previous PDP protocols consider all copies to be stored on only one cloud storage server. In some degree, multi-copy makes little sense in such circumstance. Furthermore, many PDP protocols depend on the technique of public key infrastructure (PKI), which suffers many types of security vulnerabilities and also brings heavy communicational and computational cost. To increase the security and efficiency, we provide a novel identity-based PDP scheme of multi-copy on multiple cloud storage servers. In our scheme, all copies are delivered to different cloud storage servers, which work cooperatively to store the customer's data. By the homomorphic verifiable tags, the integrity of all copies can be checked simultaneously. The system model and security model of our scheme are provided in the paper. The security for our scheme is proved based on the computation Diffie-Hellman (CDH) hard problem. Analysis and experimental evaluation show that our scheme is efficient and practical. The proposed scheme is the first identity-based PDP scheme for multi-copy and multi-cloud servers.

Provable Data Possession Schemes from Standard Lattices for Cloud Computing

Abstract Provable Data Possession (PDP) is of crucial importance in public cloud storage since it allows users to check the integrity of their outsourced data without downloading it. However, the existing PDP schemes, which are based on classical number-theoretic assumptions, are insecure under quantum attacks. In this paper, we propose the first PDP scheme from standard lattices, using a specific leveled fully homomorphic signature (FHS) scheme. To remove the complex key management of PDP cryptosystem on the public key infrastructure (PKI) setting, we employ a specific leveled identity-based (ID-based) FHS scheme to construct the first ID-based PDP scheme from standard lattices. Our two PDP schemes are secure under the standard small integer solution (SIS) assumption, which is conjectured to withstand quantum attacks. Furthermore, we conduct experimental evaluations to validate the feasibility of the proposed PDP schemes in practice.