Currently, many companies and institutions use centralized or distributed databases to store massive amounts of data. However, the use of untrusted centralized third-party auditors can result in security issues because these auditors may be malicious and tamper with or delete user data. This poses a significant challenge for ensuring the reliability of the data verification results. Although introducing a third-party auditor can help address this issue, it may also be untrustworthy and collude with the database service provider to forge false data verification results. In this study, we propose a data integrity verification scheme using smart contracts (DIV-SC) to address this challenge in a centralized database environment. Our approach utilizes blockchain technology as a decentralized third-party auditor, ensuring that the information stored on the blockchain is immutable and cannot be tampered with maliciously. In addition, smart contracts deployed on the blockchain can ensure that the verification procedures are correct and are not affected by any malicious party. We also leverage game theory to improve the reliability of multiple verifications, reduce verification time and improve overall performance. Our proposed scheme reduces the total verification time consumption by up to 53.44% while increasing the number of verifiable times by nearly 3.8 times, compared to conventional data integrity verification schemes.
We present a general purpose, privacy-preserving framework for verifying user attributes. The framework is designed for users (e.g., a job candidate) to allow a challenger (e.g., a prospective employer) to verify whether the usermeets a particular requirement (e.g., does the candidate hold a valid driving license?), without leaking any other information about the user. Importantly, the user is an active part of the challenge-verification process, which ensures that challenges cannot be made without the user’s full knowledge and participation. The framework is decentralized and requires a public blockchain. A smart contract is used to manage the challenge-verification process, and zero-knowledge proofs are used to verify challenges in a privacy-preserving manner. We implement a simplified version of the framework using smart contracts deployed on the Ethereum blockchain, and we simulate some simple use cases. All simulation code is available open-source (https://github.com/lifeisbeer/BlockVerify).
Blockchains are a new approach to creating distributed networks that were first introduced in 2008. It allows the formation of peer-to-peer networks based on consensus, forming chains from accepted blocks without requiring a central authority or centralized controller. A prominent application of this technology is its use in decentralized storage systems. Individuals in decentralized storage networks rent unused hardware storage space to other individuals. A decentralized network utilizing end-to-end encryption eliminates the risk of data loss associated with centralized data control by enabling clients to transmit their files securely. The storage providers must prove that they have kept unaltered files in this network for this time. Many studies have been conducted in this specific domain, most targeting storage capacity and efficiency, but a security, integrity and privacy loophole need to be addressed. This paper presents an overview of blockchain-based storage systems and how they work, followed by a comparison with cloud-based storage networks and a survey of various decentralized storage networks like SIA, File coin, and Storj available on the market. Next, we discuss the advantages and disadvantages of blockchain-based storage. In our final discussion, we examine the security problems of decentralized storage networks and explore potential solutions and research directions for the future.
This paper delves into two legal models for zero-knowledge proof protocols in the context of the eIDAS 2.0 Regulation: a trust service or a software product. The ARIES: reliAble euRopean Identity EcoSystem EU project highlighted the need for a legal framework for stakeholders to accept proof of the existence of user data with legal certainty, while Hyperledger Indy shows that ZKP solutions are currently commercialized, stressing deficiencies in the eIDAS 2.0. An overview of ZKP applied to identity, its relationship to the European Digital Identity Wallet and the electronic attestations of attributes, both introduced by the eIDAS 2.0, and Self-Sovereign Identity systems, leads to the central question of proof of the existence of user-held data as a trust service or as a software product and its data privacy implications for each approach. Finally, we outline a possible solution based on the product approach for future work. Our findings reveal that ZKP technology must have legal value and a presumption system to be effective. However, the path we take could lead us either to develop a system of surveillance and control in electronic environments or to build an environment where we share not the data itself but proof of its existence.
Consensus protocols are critical for any blockchain technology, and Proof-of- Stake (PoS) protocols have gained popularity due to their advantages over Proof-of- Work (PoW) protocols in terms of scalability and efficiency. However, existing PoS mechanisms, such as delegated and bonded PoS, suffer from security and usability issues. Pure PoS (PPoS) protocols provide a stronger decentralization and offer a potential solution to these problems. Algorand, a well-known cryptocurrency, employs a PPoS protocol that utilizes a new Byzantine Agreement (BA) mechanism for consensus and Verifiable Random Functions (VRFs) to securely scale the protocol to accommodate many participants, making it possible to handle a growing number of clients with ease. In this research, we explore, implement, and document all the essential steps of the algorithm for any given round that leads to publishing a block, and we evaluate the performance and stability of Algorand using various numbers of users, their stakes, and network settings. To simulate the protocol, we extend the Spar- tanGold blockchain framework, which currently uses a PoW protocol, and convert it into a PoS model. Our results show that the PPoS protocol developed by Algorand is highly scalable, achieving consensus quickly and efficiently, even in the presence of malicious users or network partitions and offers higher security and Byzantine fault tolerance compared to traditional PoW and other PoS-based protocols.
Zero-Knowledge Proof (ZKP) is a useful tools for proving that a prover possesses a secret without revealing it to the verifier. Designated Verifier Proof (DVP) is a special type of ZKP that adds the ability to restrict the identity of verifiers so that only pre-determined authorized verifiers can verify. However, DVP and other similar schemes do not work if the verifier provides some additional information to indicate the provenance of the proof. Since this information may be stored on the blockchain, the proof can be accepted by third parties even if the verifier is willing to protect the privacy of the prover. In this paper, we propose the concept of Blockchain Designated Verifier Proof (BDVP), and design a BDVP scheme suitable for blockchain applications. The key technique behind our BDVP scheme is that the verifier can forge a fake secret to simulate the proof. Therefore, a third party cannot determine whether the prover possesses the secret. This enables the verifier to protect the privacy of the prover, which is required by law or regulation. We also address the quantum attack problem and propose a post-quantum solution. We evaluate and compare the performances of the proposed protocol with other related protocols.
Due to the ease with which false documents can be produced, strict verification and authentication procedures for some original documents may be required. A well-crafted fake document is never easily identified. As a result, a secure method of document verification is crucial. It is possible to cut costs and reduce document verification time from days to a few seconds by utilizing blockchain technology. Blockchain is a decentralized peer-to-peer network that provides security, dependability, authenticity, immutability, and transparency. It is resistant to modifications by design. This work involves developing a complete decentralized blockchain-based document verification system for multiple organizations. The project is built on the Ethereum public blockchain, which makes it flexible and suited for cooperation between various parties. We have used the InterPlanetary File System (IPFS) to store crucial documents. IPFS uses a decentralized protocol, which helps us achieve our goal of making a completely decentralized system. The backend of the system is a website developed on the React framework. The developed system is for multiple organizations. It has an admin verification system, which includes a payment system. Multiple organizations can control their separate platforms with different verifier panels from their own organizations. Only the admin can add verifiers to the system. He/she can choose suitable candidates from all the profiles created by that organization and give the person the authority to check the authenticity of the uploaded documents. The Admin adds a verifier with the person’s wallet address. The uploaded documents get checked by authorized verifiers. The status of the document, whether it is an authentic document or not, is determined by the votes of 50% of the verifiers. This system can verify the authenticity of documents of all kinds more securely than any other conventional system.
Cryptography is one of the most important approaches to keep digital communication in lock and key and therefore guarantees the privacy, integrity and authenticity of the data by means of complex coding. Cryptographic techniques have arisen centuries ago and the old techniques have continued to evolve as today’s challenges are cloud computing, data storage and retrieval as well as authenticated users. With the widespread spread of cloud environments, trust-enabling systems with cutting-edge technologies such as Zero Knowledge Proofs and blockchain emerged to increase privacy and security. By examining the notion of trust localization, this study draws attention to a use of Gateways as access control points to sensitive information reducing the dependence on the central cloud infrastructures. Additionally, source authentication and authorization provided by Acaras and PKI is studied regarding their integration and effectiveness. The research examines the current challenges in cryptographic security and current findings of cryptographic security and investigates what the future of cryptographic security to build trust and security in modern digital systems..
Cloud computing has become an essential technology for delivering infrastructure and data service needs with lower cost, low effort and high scalability, hence it is increasingly implemented in all aspects of the IT industry. Despite the quick adoption of cloud computing, the problem of information security is still not fully resolved. Information security issues are still hampering the evolution of cloud computing to some extent and need to be addressed. Blockchain is one of the decentralized processes in a worldview that works with parallel and distributed ledger technology, the application process, and service-oriented design. However, the primary security issue is key leakage and third parties easily hack the secured information. To address this issues, in this novel presents Blockchain based Proof of staking with Elliptic Curve Encryption (BPECE) algorithm is used to secure data transmission in the cloud. This proposed method efficiently checks each node verification using Policy based Key Authentication (PBKA) algorithm. The proposed technique generates public key for each document. Thus the proposed method gives better security performance than previous methods.
Blockchain Technology Applications and Security
Cloud Data Security Solutions
Advanced Steganography and Watermarking Techniques
In the current technology development scenario numerous data are handled by users for various purposes. Data become an important asset of the company. Data are utilized for various improvements of the organization full stop keeping the data in a secured way is crucial in current Internet world. Data are scrambled into various pieces in distributed computing systems for various reasons. In spite of distributed peer to peer storage and messaging systems such as ethereum swarm and ethereum Whisper and block chain Technology and efficient Framework is implemented. The storage need to be adaptive and effective during the centralized access. Comparing with the cloud based storage systems decentralized storage mechanism are economically good for all industries. Storing files in a decentralized system need robust security Framework such as block chain. The security of the file is ensured by making Complex encryption and decryption process. The proposed model considers these constraints an implemented and robust securing method using block chain Technology (RFSR). Here the files are stored and retrieved using interplanetary file systems (IPFS). Distributor application tap enabled secure computing system is implemented here.
As more and more data is produced, finding a secure and efficient data access structure has become a major research issue. The centralized systems used by medical institutions for the management and transfer of Electronic Medical Records (EMRs) can be vulnerable to security and privacy threats, often lack interoperability, and give patients limited or no access to their own EMRs. In this paper, we first propose a privilege-based data access structure and incorporates it into an attribute-based encryption mechanism to handle the management and sharing of big data sets. Our proposed privilege-based data access structure makes managing healthcare records using mobile healthcare devices efficient and feasible for large numbers of users. We then propose a novel distributed multilevel EMR (d-EMR) management scheme, which uses blockchain to address security concerns and enables selective sharing of medical records among staff members that belong to different levels of a hierarchical institution. We deploy smart contracts on Ethereum blockchain and utilize a distributed storage system to alleviate the dependence on the record-generating institutions to manage and share patient records. To preserve privacy of patient records, our smart contract is designed to allow patients to verify attributes prior to granting access rights. We provide extensive security, privacy, and evaluation analyses to show that our proposed scheme is both efficient and practical.
Blockchain (BC) has recently paved the way for developing Decentralized Identity Management (IdM) systems for different information systems. Researchers widely use it to develop decentralized IdM systems for the Health Internet of Things (HIoT). HIoT is considered a vulnerable system that produces and processes sensitive data. BC-based IdM systems have the potential to be more secure and privacy-aware than centralized IdM systems. However, many studies have shown potential security risks to using BC. A Systematic Literature Review (SLR) conducted by the authors on BC-based IdM systems in HIoT systems showed a lack of comprehensive security and risk management frameworks for BC-based IdM systems in HIoT. Conducting a further SLR focusing on risk management and supplemented by Grey Literature (GL), in this paper, a security taxonomy, security framework, and cybersecurity risk management framework for the HIoT BC-IdM systems are identified and proposed. The cybersecurity risk management framework will significantly assist developers, researchers, and organizations in developing a secure BC-based IdM to ensure HIoT users' data privacy and security.
William Hughes, Tobias Magnusson, Alejandro Russo, Gerardo Schneider
Smart contracts are self-executing programs running in the blockchain allowing for decentralised storage and execution without a middleman. On-chain execution is expensive, with miners charging fees for distributed execution according to a cost model defined in the protocol. In particular, transactions have a high fixed cost. We present MultiCall, a transaction-batching interpreter for Ethereum that reduces the cost of smart contract executions by gathering multiple users’ transactions into a batch. Our current implementation of MultiCall includes the following features: the ability to emulate Ethereum calls and create transactions, both from MultiCall itself and using an identity unique to the user; the ability to cheaply pay Ether to other MultiCall users; and the ability to authorise emulated transactions on behalf of multiple users in a single transaction using hash-based authorisation rather than more expensive signatures. This improves upon a previous version of MultiCall. Our experiments show that MultiCall provides a saving between 57% and 99% of the fixed transaction cost compared with the standard approach of sending Ethereum transactions directly. Besides, we also show how to prevent an economic attack exploiting the metatransaction feature, describe a generic protocol for hash-based authorisation of metatransactions, and analyse how to minimise its off-chain computational and storage cost.
Diego F. Aranha, Youssef El Housni, Aurore Guillevic
Elliptic curves have become key ingredients for instantiating zero-knowledge proofs and more generally proof systems. Recently, there have been many tailored constructions of these curves that aim at efficiently implementing different kinds of proof systems. In this survey we provide the reader with a comprehensive overview on existing work and revisit the contributions in terms of efficiency and security. We present an overview at three stages of the process: curves to instantiate a SNARK, curves to instantiate a recursive SNARK, and also curves to express an elliptic-curve related statement. We provide new constructions of curves for SNARKs and generalize the state-of-the-art constructions for recursive SNARKs. We also exhaustively document the existing work and open-source implementations.
Decentralized Storage Networks (DSNs) can gather storage resources from mutually untrusted providers and form worldwide decentralized file systems. Compared to traditional storage networks, DSNs are built on top of blockchains, which can incentivize service providers and ensure strong security. However, existing DSNs face two major challenges. First, deduplication can only be achieved at the directory-level. Missing file-level deduplication leads to unavoidable extra storage and bandwidth cost. Second, current DSNs realize file indexing by storing extra metadata while blockchain ledgers are not fully exploited. To overcome these problems, we propose FileDAG, a DSN built on DAG-based blockchain to support file-level deduplication in storing multi-versioned files. When updating files, we adopt an increment generation method to calculate and store only the increments instead of the entire updated files. Besides, we introduce a two-layer DAG-based blockchain ledger, by which FileDAG can provide flexible and storage-saving file indexing by directly using the blockchain database without incurring extra storage overhead. We implement FileDAG and evaluate its performance with extensive experiments. The results demonstrate that FileDAG outperforms the state-of-the-art industrial DSNs considering storage cost and latency.
The Ethereum blockchain’s smart contract is a programmable transaction that performs general-purpose computations and can be executed automatically on the blockchain. Leveraging this component, blockchain technology (BT) has grown beyond the scope of cryptocurrencies and can now be applicable in various industries other than finance. In this paper, we investigated the current trends in Ethereum-based decentralized applications (DApps) to be able to categorize and analyze the DApps to measure the complexity of smart contracts behind them, their level of security and their correlation to the maintainability of the DApps. We leveraged the source code analysis, security analysis, and the developmental metadata of the DApps to infer this correlation. Based on our findings, we concluded that the maintainability of Ethereum DApps is proportional to the code size, number of functions, and, most importantly, the number of outgoing invocations and statements in the smart contracts.
Yuncheng Qiao, Linhai Cheng, Qiujun Lan, Yiran Wang
Data sharing among different institutions can enhance the integrity of information to evaluate the credit level of financing enterprises more accurately, but it also faces the problems of privacy leakage and data fraud. To solve these problems, this paper proposes a complete linear credit evaluation system with secure sharing and multiparty collaborative computing based on Hyperledger Fabric Blockchain named LEChain. The system consists of four modules: distributed ledger, access control, security aggregation and model storage. With the help of 1-out-of-N oblivious transmission protocol, incorporating elementary matrix transformation data security aggregation realizes the privacy of data transmission and collaborative computation. Finally, a security analysis is given to show the privacy and compliance of the data aggregation.
As a distributed ledger jointly maintained by multiple parties that do not trust each other [1], the data services provided by the blockchain system must ensure that the results cannot be tampered with. However, the query on blockchain is affected by the chain structure. This paper adds relational semantics to block data. So, it can support three basic query methods and accelerate a unique query method for blockchain. In addition, we design four types of indexes to ensure the efficiency of data query. We optimized the query processing and tested it in the edge device scenario and taking the Internet of Vehicles as an example. The result shows that the response time for the query is significantly reduced.
Zhoujie Zhang, Tao Lei, Can Cui, Yunhao Huang · 8 authors
With the widespread application of power system digital technology and the advancement of dispatch control cloud construction, the development of power grid regulation business presents the basic characteristics of many business participants, frequent business interactions, and large data exchange. The alliance chain technology in blockchain technology has become an important basis for the research of this paper because of its native support for multi-party business scenarios. Based on the alliance blockchain technology, this paper designs a multi-channel data isolation scheme for the grid dispatching control business to achieve efficient data sharing within a controllable range. At the same time, in order to ensure the security of the private data in the grid dispatching control business in the business interaction process. Furthermore, this paper designs a business interaction process for private data based on the zero-knowledge verification algorithm. Combined with smart contract technology, it automatically completes the entire network verification process of data encryption and zero-knowledge credentials, and realizes data security interaction in secret scenarios.