In this paper, an efficient data structure for storage, management, and security in blockchain systems is presented. This efficient structure is based on the AVL (Adelson-Velsky and Landis) tree and make an extension for the purpose of management and security. We first present a new storage structure for efficient data search based on the AVL tree. Next we expand this data structure and apply to the management and security of the blockchain ledger. The way of management for distributed account/data is divided into two operations, namely splitting and merging. This paper also makes a discussion about the significance of these two operations. We show a detailed description and make mathematical analysis with proof for the performance of all mechanisms proposed in this paper. In addition, a mechanism of dual authentication is also proposed and to provide a better tamper-proof.
Muhammad Saeed, Rashid Amin, Muhammad Umar Aftab, Naeem Ahmed
Security is a big challenge for developing and implementing IoT in smart building situations. In this context, our goal is to create a secure blockchain-based trust management system. To do so we take advantage of the security features that blockchain technology provides in terms of reliability, traceability, and data integrity. We design and implement a blockchain-based trust strategy that collects trust evidence, assigns each device a trust score, and securely stores and shares them with other devices in the network by integrating them into blockchain exchanges. According to the findings of our performance evaluation, our concept includes security features such as tamper-proofing and assault resistance, reliability, and easy implementation for IoT environments and applications.
Sumit Kumar Rana, Sanjeev Rana, Kashif Nisar, Ag Asri Ag Ibrahim · 7 authors
Healthcare, one of the most important industries, is data-oriented, but most of the research in this industry focuses on incorporating the internet of things (IoT) or connecting medical equipment. Very few researchers are looking at the data generated in the healthcare industry. Data are very important tools in this competitive world, as they can be integrated with artificial intelligence (AI) to promote sustainability. Healthcare data include the health records of patients, drug-related data, clinical trials data, data from various medical equipment, etc. Most of the data management processes are manual, time-consuming, and error-prone. Even then, different healthcare industries do not trust each other to share and collaborate on data. Distributed ledger technology is being used for innovations in different sectors including healthcare. This technology can be incorporated to maintain and exchange data between different healthcare organizations, such as hospitals, insurance companies, laboratories, pharmacies, etc. Various attributes of this technology, such as its immutability, transparency, provenance etc., can bring trust and security to the domain of the healthcare sector. In this paper, a decentralized access control model is proposed to enable the secure interoperability of different healthcare organizations. This model uses the Ethereum blockchain for its implementation. This model interfaces patients, doctors, chemists, and insurance companies, empowering the consistent and secure exchange of data. The major concerns are maintaining a history of the transactions and avoiding unauthorized updates in health records. Any transaction that changes the state of the data is reflected in the distributed ledger and can be easily traced with this model. Only authorized entities can access their respective data. Even the administrator will not be able to modify any medical records.
The fair exchange problem has faced for a long time the bottleneck of a required trusted third party. The recent development of blockchains introduces a new type of party to this problem, whose trustworthiness relies on a public ledger and distributed computation. The challenge in this setting is to reconcile the minimalistic and public nature of blockchains with elaborate fair exchange requirements, from functionality to privacy. Zero-knowledge contingent payments (ZKCP) are a class of protocols that are promising in this direction, allowing the fair exchange of data for payment. We propose a new ZKCP protocol that, when compared to others, requires less computation from the blockchain and less interaction between parties. The protocol is based on two-party (weak) adaptor signatures, which we show how to instantiate from state of the art multiparty signing protocols. We improve the symbolic definition of ZKCP security and, for automated verification with Tamarin, we propose a general security reduction from the theory of abelian groups to the theory of exclusive or.
Cloud computing has enabled outsourced storage of large amounts of data and reliable access to it. Privacy of remotely stored data has been a concern for every data owner, which would be resolved by applying suitable encryption mechanism. On the other hand, searching is difficult in the case of encrypted documents. In this work, we propose a Blockchain assisted Fuzzy search over encrypted data named BSMFS. BSMFS is resistant against leakage of information by well-known attacks like search, access and volume pattern leakage attacks. A smart contract is developed for Ethereum blockchain to assist the interaction between data user and cloud server, along with a bloom filter for efficient search. Experimental analysis is performed on Ethereum test networks to check the feasibility of BSMFS.
Aug 1, 2022·2022 IEEE International Conferences on Internet of Things (iThings) and IEEE Green Computing & Communications (GreenCom) and IEEE Cyber, Physical & Social Computing (CPSCom) and IEEE Smart Data (SmartData) and IEEE Congress on Cybermatics (Cybermatics)
Secure comparison is an important problem in the field of secure computing. A classic example is the Millionaires' problem, which is securely compares the wealth of two millionaires without revealing their wealth. However most traditional secure comparison protocol requires autonomous computation among the participants. It is necessary to ensure that the model of the participants is a semi-honest model, otherwise the protocol will not be able to execute correctly. In this paper, we introduce a semi-honest judge to improve the Damgård-Geisler-KrØigaard(DGK) comparison protocol by using techniques such as zero-knowledge proof and homomorphic encryption. The improved protocol is not only applicable to the malicious participant model, but also the introduced judge would not get any information of data. At last, the security analysis shows that the proposed scheme in this paper can guarantee the data fairness of the comparison protocol while ensuring the privacy security of the participants.
The traditional identity authentication method not only brings single point of failure, but also easily leads to privacy leakage. In order to solve the problem of information leakage caused by identity authentication, this paper proposes a consortium blockchain-based minimal signature authentication scheme MDSA. We use the structure of Merkle Tree to generate digital credentials for users. In particular, this scheme combining zero-knowledge proofs to provide compliance proofs for user identity attribute values to further achieve minimal authentication. We propose an attribute-based authentication model. In general, our scheme allows for self-sovereign identity, secure creation, and distributed storage. We use FISCO BCOS-based blockchain prototype system as our testbed, and the evaluations show that MDSA is feasible and secure, with linear increases in credential generation and authentication overhead.
Davide Martintoni, Valerio Senni, Ernesto Gómez-Marín, Antonio Cabrera
Supply chain management is a critical aspect for every manufacturing business, in particular for safety critical systems where quality assessment and requirement satisfaction are evaluated in order to guarantee a certification of the final system. In this paper we present a blockchain-based methodology that focuses on enforcing strict data access control and that securely includes manufacturing equipment in the supply chain management process. The methodology provides cyber-security guarantees exploiting secure automated interaction between a blockchain supply chain management system and industrial manufacturing devices. A prototype of the proposed approach is implemented with state-of-the-art distributed ledger technologies integrating low-power devices hardened through the application of hardware security modules.
Non-Fungible Tokens (NFTs) are digital assets that represent real-world objects like art, music and videos. However, NFTs according to current standards have no provisions for the copyright traceability of the off-chain data, which greatly hinders the sustainability of the NFT community. In this paper, we propose a new NFT model, which is a synergy of a new economic mechanism backed by game theory and two supplementary algorithms to handle the off-chain data. The economic mechanism is first proposed to motivate participants to maintain the off-chain raw data. Then, the model includes two supplementary algorithms, the version algorithm and validation algorithm, to verify the NFT’s ownership and copyright. We implement our model in Solidity on Ethereum and conduct experiments based on the real-world dataset from the largest NFT marketplace OpenSea. Our evaluation demonstrates that our model is a promising attempt towards the copyright traceability of the off-chain data for NFTs.
Blockchain is a distributed ledger that combines technologies such as cryptography, consensus mechanism, peer-to-peer transmission, and time stamping. The rapid development of blockchain has attracted attention from all walks of life, but storage scalability issues have hindered the application of blockchain. In this paper, a scalable blockchain storage model based on Distributed Hash Table (DHT) and the InterPlanetary File System (IPFS) was proposed. This paper introduces the current research status of the scalable blockchain storage model, as well as the basic principles of DHT and the InterPlanetary File System. The model construction and workflow are explained in detail. At the same time, the DHT network construction mechanism, block heat identification mechanism, new node initialization mechanism, and block data read and write mechanism in the model are described in detail. Experimental results show that this model can reduce the storage burden of nodes, and at the same time, the blockchain network can accommodate more local blocks under the same block height.
Blockchains are meant to be persistent: posted transactions are immutable and cannot be changed. When a theft takes place, there are limited options for reversing the disputed transaction, and this has led to significant losses in the blockchain ecosystem. In this paper we propose reversible versions of ERC-20 and ERC-721, the most widely used token standards. With these new standards, a transaction is eligible for reversal for a short period of time after it has been posted on chain. After the dispute period has elapsed, the transaction can no longer be reversed. Within the short dispute period, a sender can request to reverse a transaction by convincing a decentralized set of judges to first freeze the disputed assets, and then later convincing them to reverse the transaction. Supporting reversibility in the context of ERC-20 and ERC-721 raises many interesting technical challenges. This paper explores these challenges and proposes a design for our ERC-20R and ERC-721R standards, the reversible versions of ERC-20 and ERC-721. We also provide a prototype implementation. Our goal is to initiate a deeper conversation about reversibility in the hope of reducing some of the losses in the blockchain ecosystem.
Maha Ayub, Tania Saleem, Muhammad Umar Janjua, Talha Ahmad
In migrating and upgrading an Ethereum smart contract, it is necessary to transfer both the code as well as the stored data. Various methods attempt to migrate or upgrade a smart contract, but they are mostly manual, error-prone, and applicable only before deployment. Further, they have challenges in extracting the storage state of complex mapping data structures along with their keys. In this work, we present Smartmuv as an automatic source-code-based static analysis tool to analyze and extract the state from the storage-trie of smart contracts. Based on the abstract syntax tree and the control flow graphs of the Solidity source code, the tool analyzes each state variable including mapping types along the inheritance hierarchy. It also provides the upgrade algorithm that initializes the extracted state in the constructor of new smart contract. Smartmuv safely approximates the origin of the keys used in the mapping to extract values and has been able to extract the mapping state of 23,673 smart contracts with 95.7% overall precision. Moreover, we also validate the Smartmuv’s extracted state with the third-party tool Etherscan.
Abstract In today’s world, 96% of all goods depend on chemicals. Chemical industry plays vital role in supply chain. Chemical supply chain consists of multiple stakeholders including raw material suppliers to end user customers. Based on regulations, several product documents are needed to be supplied with the chemicals till the end of the life cycle. Blockchain based document traceability offers a viable solution to create a decentralized distributed shared platform for a secure, immutable, transparent, permanent, trustworthy, and accountable system for all the stakeholders involved. In this paper, an overview of the document traceability, current challenges and envisage how Blockchain and smart contracts address those challenges are presented. Based on the analysis, it is proposed to use using Hyperledger Fabric, an open-source private blockchain to meet the document traceability requirements such as security, privacy, scalability, authentication, and authorization. The proposed Blockchain architecture provides a feasible solution to build and deploy an end-to-end decentralized application in the chemical supply chain industry for document traceability.
In the connected world of Industrie 4.0, not only the access to information becomes more and more important, but also secure, standardized, and machine-interpretable communication between assets. The identification of assets forms the basis for all emerging processes, which leads to new requirements. The authors developed a concept to establish the identity of Industrie 4.0 components in decentralized systems by providing a decentralized identity and access management based on distributed ledger technology and integrated this into the concept of the Industrie 4.0 language. The use of decentralized identifiers guarantees more security and reliability for the involved actors in the value chain. Thus, authentication and authorization can be carried out solely between the involved actors without the use of centralized identity providers or certification authorities.
A peer-to-peer (P2P) decentralized information-sharing network is used to share data and maintain security, privacy, and integrity standards called blockchain. In this case, information sharing and updating require regular simplification. The presented systematic review mainly focuses on the interoperability of electronic health records (EHRs) using blockchain. Correspondingly, 18 blockchain-based solutions were selected to address the interoperability challenges of EHRs. The limitation of solutions includes reliability, privacy, integrity, sharing, and standards. This systematic review contains six phase’s research question, research phase, article selection, abstract-based keyword, data extraction, and progress tracking. Various Web resources such as Google Scholar, Web of Science, and IEEE are used to extract the relevant manuscripts. Primarily, 18 articles were selected to present the interoperable requirements of EHRs using blockchain, standards of blockchain-based EHRs, and solutions for interoperability of EHRs using blockchain. The conducted study explains the best available interoperable blockchain-based EHR standards, implementations, applications, and challenges.
Xingguo Jiang, Aidong Sun, Yan Sun, Hong Luo · 5 authors
As the smart grid develops rapidly, abundant connected devices offer various trading data. This raises higher requirements for secure and effective data storage. Traditional centralized data management does not meet the above requirements. Currently, smart grid with conventional consortium blockchain can solve the above issues. However, in the face of a large number of nodes, existing consensus algorithms often perform poorly in terms of efficiency and throughput. In this paper, we propose a trust-based hierarchical consensus mechanism (THCM) to solve this problem. Firstly, we design a hierarchical mechanism to improve the efficiency and throughput. Then, intra-layer nodes use an improved Raft consensus algorithm and inter-layer nodes use the Byzantine Fault Tolerance algorithm. Thirdly, we propose a trust evaluation method to improve the election process of Raft. Finally, we implement a prototype system to evaluate the performance of THCM. The results demonstrate that the consensus efficiency is improved by 19.8%, the throughput is improved by 12.34%, and the storage is reduced by 37.9%.
In recent years, blockchain holds promise to impact a wide range of application areas, but it still suffers from technical challenges such as security and scalability. The increase in the number of transactions puts blockchains under data storage pressure. The emergence of cross-chain technologies connects different blockchains and relieves the data storage pressure. However, the existing research generally focuses on the technical realization of cross chain, lacking in-depth research on consistency issues like data integrity verification of cross-chain interaction. In this paper, we propose a decentralized cross-chain data integrity verification scheme (DCIV) from the point of view of governing the chain by chain. We adopt supervision chain to audit the integrity of data in cross-chain interaction. We preprocess the off-chain original data in the form of Merkle tree. Before cross-chain interaction, we process the data with KZG polynomial commitment. During the auditing period, the supervision chain generates a challenge and verifies the integrity of cross-chain data. In particular, we add audit digests into the structure of transactions in blockchain to reduce the storage burden during auditing. Theoretical and experimental analyses demonstrate that DCIV can verify the integrity of data in cross-chain interaction, achieving secure and accurate cross-chain data sharing.
Amna Amanat, Muhammad Rizwan, Carsten Maple, Yousaf Bin Zikria · 6 authors
Healthcare information is essential for both service providers and patients. Further secure sharing and maintenance of Electronic Healthcare Records (EHR) are imperative. EHR systems in healthcare have traditionally relied on a centralized system (e.g., cloud) to exchange health data across healthcare stakeholders, which may expose private and sensitive patient information. EHR has struggled to meet the demands of several stakeholders and systems in terms of safety, isolation, and other regulatory constraints. Blockchain is a distributed, decentralized ledger technology that can provide secured, validated, and immutable data sharing facilities. Blockchain creates a distributed ledger system using techniques of cryptography (hashes) that are consistent and permit actions to be carried out in a distributed manner without needing a centralized authority. Data exploitation is difficult and evident in a blockchain network due to its immutability. We propose an architecture based on blockchain technology that authenticates the user identity using a Proof of Stake (POS) cryptography consensus mechanism and Secure Hash Algorithm (SHA256) to secure EHR sharing among different electronic healthcare systems. An Elliptic Curve Digital Signature Algorithm (ECDSA) is used to verify EHR sensors to assemble and transmit data to cloud infrastructure. Results indicate that the proposed solution performs exceptionally well when compared with existing solutions, which include Proof-Of-Work (POW), Secure Hash Algorithm (SHA-1), and Message Digest (MD5) in terms of power consumption, authenticity, and security of healthcare records.
Summary In order to improve the availability and persistence of data, lightweight cloud users want to store multiple‐replicas of the original file on the server with less local computing and storage overhead. Meanwhile, to ensure the integrity of the remote storage data, some schemes have been designed to allow public verification. However, most existing schemes only focus on malicious cloud service providers and ignore the possibility that dishonest users cheat for profit. This article implements an arbitrable data auditing scheme under multi‐replica storage. The scheme adopts a new arbitration mechanism under multi‐replica storage, makes use of the non‐tampering characteristics of smart contracts, carries out reliable verification through miners, and realizes the timely detection and punishment of any fraudulent entity. In addition, the scheme also designs a multi‐replica storage model based on the B* tree, realizes the batch verification of replica blocks, enables the fraud behavior of malicious users to be identified after data update, and improves the space utilization efficiency. The article also gives detailed security proof of the proposed scheme. The evaluation result shows our scheme not only realizes a more practical and fairer audit scheme but also has lower computational overhead than current state‐of‐the‐art multi‐replica arbitrable schemes.
Security in the communication systems rely mainly on a trusted Public Key Infrastructure (PKI) and Certificate Authorities (CAs). Besides the lack of automation, the complexity and the cost of assigning a signed certificate to a device, several allegations against CAs have been discovered, which has created trust issues in adopting this standard model for secure systems. The automation of the servers certificate assignment was achieved by the Automated Certificate Management Environment (ACME) method, but without confirming the trust of assigned certificate. This paper presents a complete tested and implemented solution to solve the trust of the Certificates provided to the servers by using the blockchain platform for certificate validation. The Blockchain network provides an immutable data store, holding the public keys of all domain names, while resolving the trust concerns by applying an automated Blockchain-based Domain Control Validation (B-DCV) for the server and client server verification. The evaluation was performed on the Ethereum Rinkeby testnet adopting the Proof of Authority (PoA) consensus algorithm which is an improved version of Proof of Stake (Po$S$) applied on Ethereum 2.0 providing superior performance compared to Ethereum 1.0.
Cong Yue, Tien Tuan Anh Dinh, Zhongle Xie, Meihui Zhang · 7 authors
Verifiable ledger databases protect data history against malicious tampering. Existing systems, such as blockchains and certificate transparency, are based on transparency logs --- a simple abstraction allowing users to verify that a log maintained by an untrusted server is append-only. They expose a simple key-value interface without transactions. Building a practical database from transparency logs, on the other hand, remains a challenge. In this paper, we explore the design space of verifiable ledger databases along three dimensions: abstraction, threat model, and performance. We survey existing systems and identify their two limitations, namely, the lack of transaction support and the inferior efficiency. We then present GlassDB, a distributed database system that addresses these limitations under a practical threat model. GlassDB inherits the verifiability of transparency logs, but supports transactions and offers high performance. It extends a ledgerlike key-value store with a data structure for efficient proofs, and adds a concurrency control mechanism for transactions. GlassDB batches independent operations from concurrent transactions when updating the core data structures. In addition, we design a new benchmark for evaluating verifiable ledger databases, by extending YCSB and TPC-C benchmarks. Using this benchmark, we compare GlassDB against four baselines: reimplemented versions of three verifiable databases, and a verifiable map backed by a transparency log. Experimental results demonstrate that GlassDB is an efficient, transactional, and verifiable ledger database system.