The Internet of Things (IoT) plays a crucial role in our daily lives. Many objects are being equipped with electronic components in order to facilitate their interconnection and integration with the Internet. Due to the growing usage of IoT devices and generated data, to ensure the reliability of the network, it is necessary to utilize scalable and effective trust management systems. This study introduces the SCoTMan model, which integrates social interactions with the capability of smart contracts for effective trust management in Social IoT (SIoT). Blockchain can enhance trust management protocols by providing a global view of data and improving the propagation of trust values. Implementing trust management algorithms in traditional decentralized architectures can be challenging, but using smart contracts can provide an efficient solution. We implemented the model on the Hyperledger Fabric platform and performed a comprehensive assessment. The model efficiently performs indirect trust computations by choosing optimized counselors and minimizing storage requirements. Multiple experiments have been carried out to assess and validate the efficiency of the model in functionality metrics such as trust convergence and success rate, as well as non-functional metrics like transaction delay, computation and communication overhead, and memory usage. We also conducted a comparative analysis to emphasize the method’s advantages over existing approaches in the literature. We introduced the Total Storage Cost metric for better comparison. The results show substantial improvements in trust convergence under limited Total Storage Cost. The proposed method demonstrates that it is possible to establish scalable trust management in the SIoT by utilizing smart contracts and social metrics.
Authentication for the Internet of Vehicles (IoV) is essential for safe IoV connection. However, because of the peculiar structure of IoV, current authentication schemes heavily rely on Road Side Units (RSUs). An excessive number of RSUs will make it difficult to synchronize updates, which will make system authentication inefficient overall and prevent the reuse of authentication results. Based on this, this paper proposes a blockchain-based secure distributed authentication scheme for IoV. First, data processing and storage are decentralized to the edge of the network to reduce the communication delay and response time with the trusted authority (TA). Second, in the IoV authentication process, smart contract technology is used to achieve automatic triggering of the authentication process, and an optimized Practical Byzantine Fault Tolerant Consensus (PBFT) algorithm is designed to add the authentication information to the blockchain ledger so that the authentication results can be reused. Finally, this paper performs formal security verification and informal security analysis using and Real-Or-Random (ROR) oracle model and AVISPA tool. In addition, this paper performs a detailed evaluation of computation overhead and communication overhead and uses SUMO for simulation verification. The security analysis and performance evaluation show that the scheme meets the security requirements of IoV while having less communication and computation overhead.
Abstract Blockchain, as a secure distributed ledger technology, has received extensive attention from academia and industry for its decentralization, comparability and traceability. This paper proposes a method for verifying data security on blockchain, and a cryptographic uploading and retrieval scheme is combined with IOTA blockchain technology. In this way, an IoT data storage and sharing model is designed to combine blockchain with IPFS. In this paper, it is found that there is a certain delay in operating on Fabric and IOTA compared to the scenarios that do not use blockchain. But Fabric has better performance in upload and download performance than IOTA. In the proposed scheme in this paper, the uploading time is stabilized between 0.8 and 1.2, and the retrieval time is stabilized between 0.43s and 0.76s, which has superior data uploading and retrieval performance than Scheme 1. Furthermore, the time to generate a key for a 50MB file is only around 1800ms, and for a 50MB file split into 6KB blocks, the time to generate a secret key is only around 36s. In this paper, when the file size reaches 5MB, the computational overhead of encryption and decryption is about 1315ms and 1283ms, respectively, and the time overhead of data consistency validation is only about 1095ms when the data block is cut into 6KB for a file of 5MB, indicating that this paper’s scheme has a lower time overhead in the generation of the secret key, encryption and decryption, and the data consistency validation. In summary, the above experiments verify the security and applicability of this paper’s scheme in data storage and verification.
Abdullah Ayub Khan, Asif Ali Laghari, Abdullah M. Baqasah, Roobaea Alroobaea · 7 authors
The robust development of the blockchain distributed ledger, the Internet of Things (IoT), and fog computing-enabled connected devices and nodes has changed our lifestyle nowadays. Due to this, the increased rate of device sales and utilization increases the demand for edge computing technology with collaborative procedures. However, there is a well-established paradigm designed to optimize various distinct quality-of-service requirements, including bandwidth, latency, transmission power, delay, duty cycle, throughput, response, and edge sense, and bring computation and data storage closer to the devices and edges, along with ledger security and privacy during transmission. In this article, we present a systematic review of blockchain Hyperledger enabling fog and edge computing, which integrates as an outsourcing computation over the serverless consortium network environment. The main objective of this article is to classify recently published articles and survey reports on the current status in the domain of edge distributed computing and outsourcing computation, such as fog and edge. In addition, we proposed a blockchain-Hyperledger Sawtooth-enabled serverless edge-based distributed outsourcing computation architecture. This theoretical architecture-based solution delivers robust data security in terms of integrity, transparency, provenance, and privacy-protected preservation in the immutable storage to store the outsourcing computational ledgers. This article also highlights the changes between the proposed taxonomy and the current system based on distinct parameters, such as system security and privacy. Finally, a few open research issues and limitations with promising future directions are listed for future research work.
Zero-knowledge range proofs (ZKRPs) allow a prover to convince a verifier that a secret value lies in a given interval. ZKRPs have numerous applications: from anonymous credentials and auctions, to confidential transactions in cryptocurrencies. At the same time, a plethora of ZKRP constructions exist in the literature, each with its own trade-offs. In this work, we systematize the knowledge around ZKRPs. We create a classification of existing constructions based on the underlying building techniques, and we summarize their properties. We provide comparisons between schemes both in terms of properties as well as efficiency levels, and construct a guideline to assist in the selection of an appropriate ZKRP for different application requirements. Finally, we discuss a number of interesting open research problems.
Blockchain technology is vital in strengthening the security of private information, particularly in the healthcare sector. Its features, such as confidentiality, decentralization, security and privacy, address challenges traditional healthcare systems face, such as phishing, denial of service and identity theft attacks. In this regard, our research paper presents a security solution specifically tailored for healthcare applications. This solution integrates decentralized identity management (DIDs) for identity verification, employs the advanced ChaCha20-Poly1305 encryption algorithm to ensure data confidentiality, and utilizes a token-based mechanism for immutable record keeping. Furthermore, it incorporates a pure proof of stake (PPoS) consensus mechanism to enhance system security while optimizing efficiency. This comprehensive and scalable system showcases improvements in cost effectiveness, time efficiency of an average of 6,5 seconds and overall data protection compared to traditional approaches used in healthcare data security.
Aušrys Kilčiauskas, Antanas Bendoraitis, Eligijus Sakalauskas
One of the main trends for the monitoring and control of business processes is to implement these processes via private blockchain systems. These systems must ensure data privacy and verifiability for the entire network here denoted by ‘Net’. In addition, every business activity should be declared to a trusted third party (TTP), such as an Audit Authority (AA), for tax declaration and collection purposes. We present a solution for a confidential and verifiable realization of transactions based on the Unspent Transaction Output (UTxO) paradigm. This means that the total sum of transaction inputs (incomes) $In$ must be equal to the total sum of transaction outputs (expenses) $Ex$, satisfying the balance equation $In=Ex$. Privacy in a private blockchain must be achieved through the encryption of actual transaction values. However, it is crucial that all participants in the network be able to verify the validity of the transaction balance equation. This poses a challenge with probabilistically encrypted data. Moreover, the inputs and outputs are encrypted with different public keys. With the introduction of the AA, the number of different public keys for encryption can be reduced to two. Incomes are encrypted with the Receiver’s public key and expenses with the AA’s public key. The novelty of our realization lies in taking additively-multiplicative, homomorphic ElGamal encryption and integrating it with a proposed paradigm of modified Schnorr identification providing a non-interactive zero-knowledge proof (NIZKP) using a cryptographically secure h-function. Introducing the AA as a structural element in a blockchain system based on the UTxO enables effective verification of encrypted transaction data for the Net. This is possible because the proposed NIZKP is able to prove the equivalency of two ciphertexts encrypted with two different public keys and different actors. This integration allows all users on the Net to check the UTxO-based transaction balance equation on encrypted data. The security considerations of the proposed solution are presented.
Today, educational data, controlled centrally by educational institutions and administrative units, may be vulnerable to damage caused by natural disasters, political instability, and wars. Simultaneously, challenges arise in accessing this data for educational activities within the framework of exchange programs or lifelong learning. In the literature, there are numerous blockchain-based studies focusing on storing and sharing data in various fields. While several studies exist on blockchain applications for certification, verification, and data sharing in the education sector, a fully decentralized infrastructure has not yet been presented. To address this issue, it is proposed that data control should shift to the hands of students, who are the rightful owners of the data, rather than being solely in the hands of educational institutions. In alignment with the decentralized internet vision, Web3, public blockchain networks are considered the most suitable infrastructure for this purpose. To meet this need, a framework named PublicEduChain has been introduced within the scope of this study. PublicEduChain allows students to store their data in smart contracts created on the public Ethereum network, making it possible to share this information with any educational institution and administrative units. Educational institutions can access student data stored in smart contracts on the public Ethereum network through Learning Management System (LMS) applications and can add data to these contracts. PublicEduChain ensures that data is managed under student ownership within a fully decentralized infrastructure. The practical steps in PublicEduChain, such as creating a smart contract, logging into LMSs with Ethereum IDs, and allowing LMSs to read and write data in the student contract, are explained in detail.
Privacy and auditability have been conflicting design requirements for blockchainbased distributed ledgers since the inception of the field.As purpose-built blockchains with permissioned consensus and client access are developing in a broad and diverse range of industries, a specific form of this dichotomy is emerging: the need to audit the handling of regulated on-ledger financial assets, such as central bank digital currencies, while preserving the privacy and confidentiality of transactions as much as possible.This paper proposes a novel, privacy-preserving, noninteractive-zero-knowledge-proof-based protocol for a blockchain-based distributed ledger, to prove conformance with fundamental compliance requirements to external auditing parties.We present an extendable implementation and demonstrate the practicality of the approach.
Alexandr Kuznetsov, Alex Rusnak, Anton Yezhov, Dzianis Kanonik · 6 authors
Blockchain technology has emerged as a revolutionary tool in ensuring data integrity and security in digital transactions. However, the current approaches to data verification in blockchain systems, particularly in Ethereum, face challenges in terms of efficiency and computational overhead. The traditional use of Merkle Trees and cryptographic hash functions, while effective, leads to significant resource consumption, especially for large datasets. This highlights a gap in existing research: the need for more efficient methods of data verification in blockchain networks. Our study addresses this gap by proposing an innovative aggregation scheme for Zero-Knowledge Proofs within the structure of Merkle Trees. We develop a system that significantly reduces the size of the proof and the computational resources needed for its generation and verification. Our approach represents a paradigm shift in blockchain data verification, balancing security with efficiency. We conducted extensive experimental evaluations using real Ethereum block data to validate the effectiveness of our proposed scheme. The results demonstrate a drastic reduction in proof size and computational requirements compared to traditional methods, making the verification process more efficient and economically viable. Our contribution fills a critical research void, offering a scalable and secure solution for blockchain data verification. The implications of our work are far-reaching, enhancing the overall performance and adaptability of blockchain technology in various applications, from financial transactions to supply chain management.
Blockchain technology has emerged as a transformative solution to enhancing data security, privacy, and transparency, especially in cloud computing environments. As cloud computing continues to grow in popularity for its flexibility, scalability, and cost-effectiveness, its reliance on centralized data management systems creates significant security vulnerabilities. Blockchain, a decentralized and distributed ledger technology, offers an innovative approach to mitigate these concerns by providing immutable and transparent data transactions. This paper examines the integration of blockchain technology with cloud computing, exploring its role in revolutionizing data security, privacy, and transparency. Through case studies and research findings, the paper evaluates the potential benefits and challenges of adopting blockchain for securing cloud infrastructures, improving service integrity, and fostering trust in cloud environments.
Marisol García‐Valls, Alejandro M. Chirivella-Ciruelos
The lack of sufficient guarantee about the authenticity of running smart contracts is a major entry barrier to blockchain networks. By authenticity,we refer to the smart contract ownership or provenance; this implies perfect matching between a published source-code and the corresponding running version of a given smart contract. Block verifiers are services that check the provenance authenticity of the logic contained in blockchain networks. Nevertheless, as a block verifier is an external verification service, it consumes time to use it; and the derived overhead may not comply with temporal requirements of time-sensitive domains like cyber-physical systems. Such systems require that the temporal cost of using external services is assessed prior to the final system deployment. To the best of our knowledge, there are no previous contributions on the determination of the temporal cost of the smart-contract provenance verification process. This paper presents the design and implementation of a middleware that assesses the temporal overhead of accessing the verification services; the middleware is hosted in the global ledger and runs the verification services over large sets of smart contracts. Our contribution is validated by providing an implementation on a real blockchain network, employing actual smart contract verifier logic, and analysing the temporal behavior of the overall system operations to comply with the time-sensitive requirements of cyber-physical systems.
Rafael Belchior, Dimo Dimov, Zahary Karadjov, Jonas Pfannschmidt · 6 authors
The field of blockchain interoperability plays a pivotal role in blockchain adoption. Despite these advances, a notorious problem persists: the high number and success rate of attacks on blockchain bridges. We propose Harmonia, a framework for building robust, secure, efficient, and decentralized cross-chain applications. A main component of Harmonia is DendrETH, a decentralized and efficient zero-knowledge proof-based light client. DendrETH mitigates security problems by lowering the attack surface by relying on the properties of zero-knowledge proofs. The DendrETH instance of this paper is an improvement of Ethereum’s light client sync protocol that fixes critical security flaws. This light client protocol is implemented as a smart contract, allowing blockchains to read the state of the source blockchain in a trust-minimized way. Harmonia and DendrETH support several cross-chain use cases, such as secure cross-blockchain bridges (asset transfers) and smart contract migrations (data transfers), without a trusted operator. We implemented Harmonia in 9K lines of code. Our implementation is compatible with the Ethereum Virtual Machine (EVM) based chains and some non-EVM chains. Our experimental evaluation shows that Harmonia can generate light client updates with reasonable latency, costs (a dozen to a few thousand US dollars per year), and minimal storage requirements (around 4.5 MB per year). We also carried out experiments to evaluate the security of DendrETH. We provide an open-source implementation and reproducible environment for researchers and practitioners to replicate our results.
Background. To ensure the protection of the biometric access control system used in unsecured communication channels, it is necessary to exclude the storage and transfer, transfer of biometric data as well as sequences generated on their basis. The paper proposes a cryptographic protocol of two-factor authentication with the zero-knowledge over the extended field GF(2m) on elliptic curves using biometric data and the private key of the user. Objective. The aim of the article is to develop a cryptographic protocol for zero-knowledge two-factor authentication based on elliptic curves using biometric data and the user’s private key, which allows increasing cryptographic strength and reducing the duration of the authentication process. Methods. The process of implementing zero-knowledge proof protocols is as follows: one user (proofer) can convince another user (verifier) that he has some secret without disclosing the secret itself. Results. A cryptographic protocol for two-factor authentication with zero-knowledge over the extended field GF(2m) of elliptic curves using user biometric data is proposed, which significantly reduces the size of the protocol parameters and increases cryptographic strength (computational complexity of the breaking). There is no leakage of private key information and biometric data of the user during the execution of the zero-knowledge proof protocol. Conclusions. The implementation of a cryptographic protocol with zero-knowledge proof two-factor authentication based on elliptic curves allows significantly reducing the size of protocol parameters and increasing the cryptographic strength (computational complexity of the breaking).
With the emergence of blockchain and smart contracts, traditional digital applications 1 such as identity management, supply chain management, banking and finance etc. are expected 2 to be transformed into Decentralized Applications (DApps). Blockchain interoperability is a new 3 and exciting aspect of blockchain technology that is quickly gaining popularity in many industries. 4 However, the widespread use of blockchains has not yet been achieved because DApps running on the 5 blockchain using smart contracts require access to authentic off-chain data. Users are more conscious 6 of their personal data privacy and consequently are more reluctant to share their data, posing a 7 challenge in the adoption of DApps. To solve this challenge, we present a novel quantum-resistant, 8 data authentication and zero-knowledge proof scheme named zk-DASTARK. Based on our proposed 9 scheme, we present a novel framework which can be used to feed authenticated off-chain data to 10 DApps without compromising user data privacy. Our proposed framework is quite efficient against 11 well-known off-chain data authentication frameworks. The proposed framework is implemented on 12 state-of-the-art quantum-resistant IOTA Blockchain and is highly efficient as it takes approximately 13 60 ms to generate a proof and approximately 10 ms to verify a proof.
The industrial internet of things (IIoT) necessitates robust cross-domain authentication to secure sensitive on-site equipment data. This paper presents a refined reputation-based lightweight consensus mechanism (LRBCM) tailored for IIoT's distributed network structures. Leveraging node reputation values, LRBCM streamlines ledger consensus, minimizing communication overhead and complexity. Comparative experiments show LRBCM outperforms competing mechanisms. It maintains higher throughput as the number of participating nodes increases and achieves a throughput approximately 10.78% higher than ReCon. Moreover, runtime analysis demonstrates LRBCM's scalability, surpassing ReCon by approximately 12.79% with equivalent nodes and transactions. In addition, as a combination of LRBCM, the proposed distributed lightweight authentication mechanism (ELAM) is rigorously evaluated against the security of various attacks, and its resilience is confirmed. Experiments show that ELAM has good efficiency while maintaining high security.
Anto Benedetti, Tiphaine Henry, Sara Tucci-Piergiovanni
Blockchain applications are witnessing rapid evolution, necessitating the integration of upgradeable smart contracts. Software patterns have been proposed to summarize upgradeable smart contract best practices. However, research is missing on the comparison of these upgradeable smart contract patterns, especially regarding gas costs related to deployment and execution. This study aims to provide an in-depth analysis of gas costs associated with two prevalent upgradeable smart contract patterns: the Proxy and diamond patterns. The Proxy pattern utilizes a Proxy pointing to a logic contract, while the diamond pattern enables a Proxy to point to multiple logic contracts. We conduct a comparative analysis of gas costs for both patterns in contrast to a traditional non-upgradeable smart contract. We derive from this analysis a theoretical contribution in the form of two consolidated blockchain patterns and a corresponding decision model. By so doing we hope to contribute to the broader understanding of upgradeable smart contract patterns.
Blockchains and distributed ledger technology offer promising capabilities for supporting collaborative business processes across organizations. Typically, approaches in this field fall into two categories: either executing the entire process model on the blockchain or using the blockchain primarily to enforce or monitor the exchange of messages between participants. Our work proposes a novel approach that sits between these two methods. We introduce a centralized process model extended with blockchain annotations, detailing the tasks of each participating organization and the extent to which blockchain technology is needed to secure task execution. This model also includes all critical data objects and specifies how their handling should be protected by the blockchain. This technical report outlines a systematic three-step method for automatically decentralizing this comprehensive model into individual local process models for each organization, coupled with a separate process model for the blockchain. This decentralized structure effectively replicates the original global process model. Our transformation approach is rule-based, focusing on creating a platform-inde-pendent model first, then a platform-specific model. Subsequently, we project the platform-specific model to obtain one model for the blockchain and one model for each participating organization.
The implementation of blockchain technology alongside Artificial Intelligence features that strengthen Internet of Things cloud-based systems through extended data protection, enhanced robotic trust, and decentralized intelligence capabilities.Both potential benefits and obstacles of building blockchain-empowered collaborative AI systems that perform secure computations across multiple parties and present architectural guidelines for privacy protection.Digital transformation now drives various industries forward because of the power combination between IoT and distributed ledger technology and their alignment with AI and edge-fog-cloud computing environments.Blockchain integration with IoT networks protects data integrity by remedying vital privacy and security problems, which creates a robust system that handles decentralized, secure data management.Blockchain technology makes financial operations secure and faster across all payment transactions, trade finance, and asset management operations to build complete trust with banking institutions.Through their mutual partnership, blockchain and robotic technologies develop advanced robotic systems that exhibit better operational performance and use strengthened security systems to address blockchain weaknesses.This leads to better dependability of AIdriven service operations.Multiple forces drive blockchain integration with AI applications because users need stronger data security basics to protect confidential data from unauthorized use or tampering, and they want more reliable robot decision authentication.
The Log-Structure Merged tree (LSM-tree) based key-value (KV) store has been widely adopted as the storage engine for blockchain systems, such as Ethereum, in which blockchain data are uniformly transformed into randomly distributed KV items for persistence. However, blockchain semantics are ignored during this process, making the blockchain storage suffer from heavy read/write amplification problems. Moreover, as the Ethereum network scales up, tremendous data further exacerbates its storage burden. Until now, most studies have focused on sharding, data archiving, decentralized distributed storage, etc., to mitigate the burden of the storage layer. However, the incompatibility between Ethereum semantics and the characteristics of the storage engine is ignored. In this paper, we present ChainKV, a new semantics-aware storage paradigm to improve the storage management performance for the Ethereum system. Firstly, based on Ethereum blockchain semantics, ChainKV separately stores different types of data in multiple storage zones in the KV store to mitigate the read/write amplification problem. Secondly, following the mechanism of the verification process in the authenticated data structure (ADS), a new ADS data transformer is proposed to exploit the data locality when persisting ADS. Moreover, a new space gaming caching policy is adopted to coordinate the cache space management for two independent storage zones. Finally, we propose an optional lightweight node crash recovery mechanism to eliminate functional redundancy between the Ethereum protocol and the storage engine. The experimental results indicate that ChainKV outperforms the prior Ethereum systems by up to 1.99× and 4.20× for synchronization and query operations, respectively
Minh-Quan Le, Hai‐Duong Le, Anh Vu Dinh-Duc, Thanh-Tung Tran
Recent blockchain-based systems for managing credentials show advantages over paper-based procedures. However, issuing credentials with blockchain could conflict with current management rules and policies. One of the possible conflicts is the auditability. Most blockchain-based systems for credentials focus on security, efficiency and privacy while ignoring the auditability of the system. In this paper, we propose a new system IU-TransCert for issuing, verifying, and auditing academic credentials. The system uses a new data structure named the Auditable Merkle Tree that enables credential issuance and built-in auditing capabilities. The auditable data fields can be customized to meet regulations. Credentials are published to the blockchain in the root node of the Auditable Merkle Tree, allowing access for auditors while preserving privacy. The system provides automated and transparent auditing processes for educational authorities to independently verify credentials without involving issuers. We also present a prototype to demonstrate feasibility, and a security analysis to examine protections against threats. The analysis and discussion shows that the proposed system could enhance credential privacy, efficiency, integrity, and auditability across the university ecosystem.
Ernesto Gómez-Marín, Luis Parrilla, Jose L. Tejero López, Diego P. Morales · 5 authors
In this work, a secure architecture to send data from an Internet of Things (IoT) device to a blockchain-based supply chain is presented. As is well known, blockchains can process critical information with high security, but the authenticity and accuracy of the stored and processed information depend primarily on the reliability of the information sources. When this information requires acquisition from uncontrolled environments, as is the normal situation in the real world, it may be, intentionally or unintentionally, erroneous. The entities that provide this external information, called Oracles, are critical to guarantee the quality and veracity of the information generated by them, thus affecting the subsequent blockchain-based applications. In the case of IoT devices, there are no effective single solutions in the literature for achieving a secure implementation of an Oracle that is capable of sending data generated by a sensor to a blockchain. In order to fill this gap, in this paper, we present a holistic solution that enables blockchains to verify a set of security requirements in order to accept information from an IoT Oracle. The proposed solution uses Hardware Security Modules (HSMs) to address the security requirements of integrity and device trustworthiness, as well as a novel Public Key Infrastructure (PKI) based on a blockchain for authenticity, traceability, and data freshness. The solution is then implemented on Ethereum and evaluated regarding the fulfillment of the security requirements and time response. The final design has some flexibility limitations that will be approached in future work.