Closed-circuit television (CCTV) cameras and black boxes are indispensable for road safety and accident management. Visible highway surveillance cameras can promote safe driving habits while discouraging moving violations. According to CCTV laws, footage captured by roadside cameras must be securely stored, and authorized persons can access it. Footages collected by CCTV and Blackbox are usually saved to the camera’s microSD card, the cloud, or hard drives locally but there are concerns about security and data integrity. These issues may be addressed by blockchain technology. The cost of storing data on the blockchain, on the other hand, is prohibitively expensive. We can have decentralized and cost-effective storage with the interplanetary file system (IPFS) project. It is a file-sharing protocol that stores and distributes data in a distributed file system. We propose a decentralized IPFS and blockchain-based application for distributed file storage. It is possible to upload various types of files into our decentralized application (DApp), and hashes of the uploaded files are permanently saved on the Ethereum blockchain with the help of smart contracts. Because it cannot be removed, it is immutable. By clicking on the file description, we can also view the file. DApp also includes a keyword search feature to assist us in quickly locating sensitive information. We used Ethers.js’ smart contract event listener and contract.queryFilter to filter and read data from the blockchain. The smart contract events are then written to a text file for our DApp’s keyword search functionality. Our experiment demonstrates that our DApp is resilient to system failure while preserving the transparency and integrity of data due to the immutability of blockchain.
Alexandru A. Maftei, Alexandru Lavric, Adrian I. Petrariu, Valentin Popa
The Internet of Things (IoT) is rapidly expanding, resulting in an exponential growth of IoT devices and an increasing need for secure data storage. Currently, data management and device interaction for IoT devices are centralized, with a central server managing the storage functions. As a novel data storage solution, blockchain technology offers security through its inherent features, such as distributivity, decentralization, immutability, and consensus mechanisms. Consensus mechanisms represents the rule set imposed by the blockchain network on the IoT devices to enhance network security. In this paper, we analyzed three types of consensus mechanisms - Proof of Work, Proof of Stake, and Proof of Authority - to determine which is best suited for use in IoT data storage solution that uses blockchain. Thus, we evaluated the consensus mechanisms on public blockchain test networks using three metrics: transaction latency, average block time, and average query time. Our obtained results show the PoS and PoA consensus mechanisms are more appropriate for IoT, exhibiting lower transaction latency, lower average block time and query time when compared to the PoW mechanism. This suggests that PoS and PoA are promising alternatives for blockchain-based IoT systems that require energy-efficient and low-latency transactions.
Joāo Otávio Chervinski, Diego Kreutz, Xiwei Xu, Jiangshan Yu
With the increasing demand for communication between blockchains, improving the performance of cross-chain communication protocols becomes an emerging challenge. We take a first step towards analyzing the limitations of cross-chain communication protocols by comprehensively evaluating Cosmos Network's Inter-Blockchain Communication Protocol. To achieve our goal we introduce a novel framework to guide empirical evaluations of cross-chain communication protocols. We implement an instance of our framework as a tool to evaluate the IBC protocol. Our findings highlight several challenges, such as high transaction confirmation latency, bottlenecks in the blockchain's RPC implementation and concurrency issues that hinder the scalability of the cross-chain message relayer. We also demonstrate how to reduce the time required to complete cross-chain transfers by up to 70% when submitting large amounts of transfers. Finally, we discuss challenges faced during deployment with the objective of contributing to the development and advancement of cross-chain communication.
The combination of blockchain and internet of things (IoT) technology realizes reliable storage of IoT data. However, the data stored on the blockchain (on-chain) face the problem of poor scalability and inefficient retrieval. In this paper, the on-chain data scalability schemes based on transactions and smart contracts are first proposed. Subsequently, on the basis of the above on-chain data scalability scheme based on transactions, an on-chain data index based on skip lists is proposed to improve the retrieval efficiency. The experimental results show that both the on-chain data scalability schemes achieve on-chain data scalability while reducing storage overhead. Meanwhile, the on-chain data index based on skip lists has significantly improved dynamic range retrieval efficiency and reduced the time complexity of single data retrieval to O(log(n)).
The rise of Internet-of-Things enables the development of smart applications devoted to improving the quality of life in urban and rural areas, thus fostering the creation of smart territories. However, some dislocated areas are underprivileged in providing such services due to the lack, inefficiency, or excessive cost of Internet access. Opportunistic networking techniques might aid in surmounting these problems. In this article, we propose a framework that relies on an untrusted Data Mule to carry data from an offline source to an online destination. In particular, we present a framework that enables the communication between different actors and a reward mechanism using Distributed Ledger Technologies, Smart Contracts, and Decentralized File Storage. The protocol involved in bringing a Client’s message online and getting back a response is thoroughly explained in all its steps and then discussed on the most important trust and security issues. Finally, we evaluate such a protocol and the whole framework through a series of communication latency tests, an analysis of the Smart Contract usage, and simulations in which buses act as Data Mules. Our results suggest the feasibility of our proposal in a smart territory scenario.
Abstract To address the problems of unclear data ownership and security in data transaction scenarios, a decentralized data transaction method and platform based on Ethereum + IPFS are proposed in this paper. The proposed method first performs similar calculations on text using natural language processing technology to realize data rights, then build a transaction body-centered data encryption; finally execute a decryption process through smart contracts to avoid malicious transaction behavior. The designed data-trading platform consists of three parts: customer front-end, back-end, and database. The database adopts the Ethereum and interplanetary file system. Experiments show that the designed platform can solve the problems of unclear data ownership and security in the process of data transactions, reduce data transaction costs, and provide safe and reliable data transaction services for buyers and sellers.
Abstract Recently, Internet‐of‐Things (IoT) based applications have shifted from centralized infrastructures to decentralized ecosystems, owing to user data's security and privacy limitations. The shift has opened new doors for intruders to launch distributed attacks in diverse IoT scenarios that jeopardize the application environments. Moreover, as heterogeneous and autonomous networks communicate, the attacks intensify, which justifies the requirement of trust as a key policy. Recently, blockchain‐based IoT solutions have been proposed that address trust limitations by maintaining data consistency, immutability, and chronology in IoT environments. However, IoT ecosystems are resource‐constrained and have low bandwidth and finite computing power of sensor nodes. Thus, the inclusion of blockchain requires an effective policy design regarding consensus and smart contract environments in heterogeneous IoT applications. Recent studies have presented blockchain as a potential solution in IoT, but an effective view of consensus and smart contract design to meet the end application requirements is an open problem. Motivated by the same, the survey presents the integration of suitable low‐powered consensus protocols and smart contract design to assess and validate the blockchain‐IoT ecosystems. We present blockchain‐IoT's emerging communication and security aspects with performance issues of consensus protocols, interoperability, and implementation platforms. A case study of a smart contract‐based blockchain‐driven ecosystem is presented with a comparative analysis of mining cost and latency, which shows its suitability in real‐world setups. We also highlight attacks on blockchain IoT, open issues, potential findings, and future directions. The survey intends to drive novel solutions for future consensus and safe, smart contract designs to support applicative IoT ecosystems.
Blockchain technology is increasingly being utilized in Internet of Things (IoT) systems to provide secure data communications and hence prevent data tampering. Private blockchain offers improved speed and efficiency for small networks controlled by a single authoritative node while maintaining the secure, transparent, and immutable characteristics of blockchain technology. Multichain, an open-source private blockchain platform, offers high flexibility in building robust IoT security solutions through customizable configurations and permissions. Key features of Multichain include rapid deployment, unlimited asset management, and streamlined data streams. In this paper, we undertake a comprehensive review of existing work on blockchain IoT solutions using Multichain. To further validate our findings, we conduct a blockchain-based simulation experiment using Multichain and aim to provide insights into the potential applicability of the Multichain platform for securing IoT systems.
Timestamps establish a means to dictate the existence of a message at a particular moment in the past. Traditional digital timestamping service utilizes Public Key Infrastructure (PKI) and thus requires the presence of a Time Stamping Authority, whose job is to ensure the message’s validity. However, with the rise of distributed computing and blockchain technology, it has become possible to obtain timestamps in a decentralized manner, eliminating the need for central authorities. Previous research involves sending transactions or utilizing a smart contract mechanism to store hashes on blockchain and validating the outcome using public ledgers. By prototyping a simple digital timestamping protocol on the Solana blockchain, this article explores the natural advantages of the Solana blockchain for timestamping, implements a smart contract of digital timestamping on the Solana blockchain, and measures its latency, costs, and performance. The initial estimation expects the accuracy of the timestamps produced by the prototype to reach the average sub-second slot time. However, due to network propagation delay, it is not always possible to hit this level. The cost incurred during the process is also analyzed and discussed. Finally, this article highlights the potential ability of the blockchain to provide modern decentralized services.
Amir Al Sadi, Carlo Mazzocca, Andrea Melis, Rebecca Montanari · 6 authors
The recent widespread novel network technologies for programming data planes are remarkably enhancing the customization of data packet processing. In this direction, the Programming Protocol-independent Packet Processors (P4) is envisioned as a disruptive technology, capable of configuring network devices in a highly customizable way. P4 enables network devices to adapt their behaviors to mitigate malicious attacks (e.g., denial of service). Distributed ledger technologies (DLTs), such as blockchain, allow secure reporting alerts on malicious actions detected across different areas. However, the blockchain suffers from major scalability concerns due to the consensus protocols needed to agree on a global state of the network. To overcome these limitations, new solutions have recently emerged. IOTA is a next-generation distributed ledger engineered to tackle the scalability limits while still providing the same security capabilities such as immutability, traceability, and transparency. This article proposes an architecture that integrates a P4-based data plane software-defined network (SDN) and an IOTA layer employed to notify about networking attacks. Specifically, we propose a fast, secure, and energy-efficient DLT-enabled architecture that combines the IOTA data structure, named Tangle, with the SDN layer to detect and notify about network threats.
Centralized and decentralized systems are prone to security breaches while storing private data. It is challenging to establish trust when an administrator is not known. Blockchain-based technologies use distributed ledgers that can be trusted, audited, validated, and verified by network nodes. The assets stored in a blockchain are immutable, timestamped, and cannot be tampered because of the integrated cryptographic mechanisms. Consensus algorithms are used to validate the transactions and blocks stored in a blockchain. Multiple research reviews focus either on various application domains of blockchain or comparative study of consensus algorithms or security aspects. This chapter aims at providing a comprehensive review on blockchain technologies, performance metrics, and guidelines for choosing a blockchain technology and consensus algorithm based on an organization's requirements and protocols. This chapter also captures concepts on blockchain types, consensus algorithms, and typical applications of blockchain with its features.
Mobile Number Portability (MNP) as a regulatory requirement for Mobile Network Operators (MNO), allows users to easily switch their operators while keeping their number. User subscription, profile management, and MNP procedures in current MNOs are handled in centralized systems and databases that rely on trusted third parties. Having a single point of failure, low scalability, high latency, imposed porting fees, data leakage in the central database, low availability, and need for re-subscription while porting procedure are the most highlighted defects of the conventional systems. Addressing these issues, we propose a Blockchain-based system to 1) manage user subscription and user profile/identity in a distributed database, and 2) mobile number and profile porting procedure. This solution eliminates any central point via managing the processes using smart contracts. Moreover, it decreases IT complexity, increases automation, provides low latency, and high confidentiality. The experiments confirm that this solution can provide fast and scalable profile management and porting solution.
The interconnection of devices in Internet of Things (IoT) networks results in a ubiquitous exchange of resources between clients and servers. This interaction involving multicast discovery requests in classical Service oriented Architectures is hardly applicable for IoT nodes that go through sleep phases to conserve energy. CoRE Resource Directory (RD) provides a CoAP-based solution, including a central node where the server registers its resources, and the client requests them. Nevertheless, the centralization of operations makes this node a point of failure vulnerable to DDoS attacks and causes a mistrusted authentication between RD and endpoint devices. The Blockchain (BC) is a valuable solution for building decentralized, trustless peer-to-peer networks that enable reliable and non-repudiable data exchange. However, its application in IoT environments is a real challenge due to the computing and storage constraints of the devices. In this paper, we propose a novel architecture based on a distributed network of RDs acting as validators in a permissioned blockchain. The aim is to safeguard the resource registration phase and define the type of data stored in the BC ledger. Three approaches are proposed, implemented, and evaluated by exploiting Hyperledger Iroha Blockchain and a CoAP library called CoAPthon. The differences between approaches regarding storage size, usability, and security are highlighted. The assessment results show the impact of each approach and discuss the possibility of a combined solution concluding with their applicability in the proposed architecture to further secure the CoAP resource registration.
Roman-Valentyn Tkachuk, Dragos Ilie, Remi Robert, Victor R. Kebande · 5 authors
This work defines a decentralized blockchain-based peer-to-peer (P2P) energy marketplace which addresses actors’ privacy and the performance of consensus mechanisms. The defined marketplace utilizes private permissioned Ethereum-based blockchain client Hyperledger Besu (HB) and its smart contracts to automate the P2P trade settlement process. Also, to make the marketplace compliant with energy trade regulations, it includes the regulator actor, which manages the issue and generation of guarantees of origin and certifies the renewable energy sources used to generate traded electricity. Finally, the proposed marketplace incorporates privacy-preserving features, allowing it to generate private transactions and store them within a designated group of actors. Performance evaluation results of HB-based marketplace with three main consensus mechanisms for private networks, i. e., Clique, IBFT 2.0, and QBFT, demonstrate a lower throughput than another popular private permissioned blockchain platform Hyperledger Fabric (HF). However, the lower throughput is a side effect of the Byzantine Fault Tolerant characteristics of HB’s consensus mechanisms, i. e., IBFT 2.0 and QBFT, which provide increased security compared to HF’s Crash Fault Tolerant consensus RAFT.
Blockchain technology is the leading and revolutionary technology in this modern era of computing. Many countries around the world are diverting towards digital currency which is the initial popular service provided by blockchain technology e.g., Bitcoin, Litecoin, etc. The main feature of blockchain is to omit the central authority by introducing distributed ledger structures. The consensus protocols play a vital role in the performance and efficiency of blockchain-based frameworks. This study introduces the solution of different e-services and associated problems that are faced in developing countries for making the system transparent, smart, and secure. These features make Web 3.0 applications, which is the ultimate goal of blockchain-based technology. This study also explains the numerous aspects of blockchain-based e-services infrastructure, implementation issues, advantages, disadvantages, and challenges. This study may help practitioners for making smart, intelligent, highly secure, and robust applications even in developing countries.
Abstract The Fog computing concept has been introduced to aid in the data processing of Internet of things applications using Cloud computing. Due to the profitable benefits of this combination, several papers have lately been published proposing the deployment of Blockchain alongside Fog computing in a variety of fields. A comprehensive evaluation and synthesis of the literature on Blockchain-Fog computing integration applications that have emerged in recent years is required. Although there have been several articles on the integration of Blockchain with Fog computing, the applications connected with this combination are still fragmented and require further exploration. Hence, in this paper, the applications of Blockchain-Fog computing integration are identified using a systematic literature review technique and tailored search criteria generated from the study objectives. This article found and evaluated 144 relevant papers. The findings of this article can be used as a resource for future Fog computing research and designs.
Petya Hristova Cvitic, Felix Dobslaw, Francisco Gomes de Oliveira Neto
A distributed ledger is the backbone of all blockchain solutions. It provides a shared database spreading across a network of nodes. The number of DL solutions and their implementations has grown in recent years. Besides the architectural and performance promises of thesesolutions, organizations seekingto implement DL also need to consider the overall quality of the software available and its ecosystem. Particularly, previous research has identified the need to better understand the testing and maintenance practices behind these types of technologies. This paper investigates the testing and maintenance of 18 different open-source projects that implement distributed ledgers. We perform a manual inspection of test artefacts and mine the history of commits, issues and contributors of the chosen projects to understand the landscape of testing and maintenance in these projects. Our findings suggest that unit and integration tests are present in most projects, they do not follow a holistic system testing approach. Moreover, projects rely on a small team of core contributors (5 on average). While the projects are continuously maintained, larger changes are uncommon. Our results can be used for benchmarking and pinpointing areas of improvement for the development of distributed ledgers.
The successful operation of Bitcoin has made its underlying blockchain technology receive wide attention. As the application scenarios of blockchain technology are enriched, the requirements for its performance are getting higher. Therefore, it is of utmost importance to effectively solve the problem of high-performance data interaction in the blockchain. In this paper, based on relevant domestic and foreign research literature, we start from the development history of blockchain technology and review the relevant research work on improving the performance of blockchain from three perspectives: on-chain interaction technology, off-chain interaction technology, and cross-chain interaction technology in turn. The on-chain and off-chain interaction technologies improve performance by improving the architecture of the blockchain system. The performance improvement solution of on-chain interaction technology is to modify and optimize the basic protocol and architecture of the blockchain itself to achieve a performance improvement. Still, the impact of this approach is limited in terms of performance improvement. The performance improvement solution of off-chain interaction technology is to transfer part of the data processing to off-chain and only return the final result to on-chain for storage and recording, which reduces the burden of on-chain operation and improves the efficiency of data processing. In terms of cross-chain interaction technology, this paper analyses four mainstream technology, namely, Notary Scheme, Side chain and Chain relay, Hash-Locking, and Distributed Private Key Control, and ultimately concludes through comparative analysis that cross-chain technology has a significant impact on improving blockchain performance. Finally, the paper provides a systematic overview of the above and an outlook on the possible future development of technologies related to enhancing blockchain performance.
Micromobility IoT devices and Connected Vehicles generate massive mobility data, crucial for time-critical safety-related data analytics. It is challenging to study and understand such data without compromising user privacy. We propose AFFIRM, a secure privacy-preserving blockchain framework for efficient, scalable and lightweight mobility data generation, validation, storage and retrieval in future Web3 applications. AFFIRM enables nearby devices to self-organize as a fog network and collaboratively train machine learning algorithms locally to securely generate, validate, store and retrieve mobility data via consensus leveraging Information Centric Networking as the underlying architecture. The proposed collaborative learning enables nodes to learn and adapt with respect to parameters related to scalability, timeliness, security, privacy, and resource consumption. We evaluate AFFIRM using mobility data from New York city and results shows it to scalably store mobility data from up to 700 devices with lower delays and overhead.
Felipe Condon, José Manuel Martínez, Young-Chon Kim, Mohamed A. Ahmed
Nowadays, many households are adopting distributed energy resources (DERs), such as photovoltaics (PV) systems and energy storage systems (ESS) which enable each house to generate and consume energy. Peer-to-peer (P2P) energy trading is a new energy trading management among prosumers and consumers in the distribution power system, allowing excess energy to be traded locally. This work aims to design and implement an oracle blockchain-based system for local energy trading among smart homes in a microgrid. The main focus is the interaction between distributed P2P networks such as blockchain and oracle networks. Our implementation consists of a private Ethereum blockchain network and a Chainlink oracle network. Smart contracts enable prosumers and consumers to trade energy in an open auction while requesting external energy data from our testbed API through the oracle network for the settlement process.
The widespread usage of smart devices with various city-centric services speeds up and improves civic life, in contrast to growing privacy and security concerns. Security issues are exacerbated when e-government service providers trade their services within a centralised framework. Due to security concerns, city-centric centralised services are being converted to blockchain-based systems, which is a very time-consuming and challenging process. The interoperability of these blockchain-based systems is also more challenging due to protocol variances, an excessive amount of local transactions that raise scalability and rapidly occupy memory. In this paper, we have proposed a framework for interoperability across various blockchain-based smart city services. It also summarises how independent service providers might continue self-service choices (i.e., local transactions) without overloading the blockchain network and other organisations. A simulated interoperability network is used to show the network’s effectiveness. The experimental outcomes show the scalability and memory optimization of the blockchain network.
This PhD dissertation concludes a three-year long research journey on the integration of Fog Computing and Blockchain technologies. The main aim of such integration is to address the challenges of each of these technologies, by integrating it with the other. Blockchain technology (BC) is a distributed ledger technology in the form of a distributed transactional database, secured by cryptography, and governed by a consensus mechanism. It was initially proposed for decentralized cryptocurrency applications with practically proven high robustness. Fog Computing (FC) is a geographically distributed computing architecture, in which various heterogeneous devices at the edge of network are ubiquitously connected to collaboratively provide elastic computation services. FC provides enhanced services closer to end-users in terms of time, energy, and network load. The integration of FC with BC can result in more efficient services, in terms of latency and privacy, mostly required by Internet of Things systems.