The computing capability of the embedded systems and bandwidth of the home network increase rapidly due to the rapid development of information and communication technologies. Many home appliances such as TVs, refrigerators, or air conditioners are now connected to the internet, then, the controlling firmware modules are automatically updatable via the network. TR-069 is a widely adopted standard for automatic appliance management and firmware update. Maintaining a TR-069 network usually involves the design and deployment of the overall security and trust infrastructure, the update file repository and the update audit mechanisms. Thus, maintaining a dedicated TR-069 network is a heavy burden for the vendors of home appliances. Blockchain is an emerging technology that provides a secure and trust infrastructure based on distributed consensus. This paper reports the results of our initial attempt to design a prototype of a multitenant TR-069 platform based on the blockchain. The core idea is to reify each automatic deployment task as a smart contract instance whose transactions are recorded in the append-only distributed ledger and verified by the peers. Also, the overall design should be transparent to the original TR-069 entities. We have built a prototype based on the proposed architecture to verify the feasibility in three key scenarios. The experimental results show that the proposed approach is feasible and is able to scale linearly in proportion to the number of managed devices.
Cheick Tidiane Bâ, Andrea Michienzi, Barbara Guidi, Matteo Zignani · 6 authors
Nowadays, Online Social Media (OSM) are among the most popular web services. Traditional OSM are known to be affected by serious issues including misinformation, fake news, censorship, and privacy violations, to the point that a pressing demand for new paradigms is raised by users all over the world. Among such paradigms, the concepts around the Web 3.0 are fueling a new revolution of online sociality, pushing towards the adoption of innovative and groundbreaking technologies. In particular, the decentralization of social services through the blockchain technology is representing the most valid alternative to current OSM, enabling the development of rewarding strategies for value redistribution, and fake news detection. However, the so-called Blockchain Online Social Media (BOSMs) are far from being mature, with different platforms that continually try to redefine their services in order to attract larger audiences, thus causing blockchain forks and massive user migrations, with the latter dominating the dynamics of the current OSM landscape, too.
Kai Qian, Yinqiu Liu, Chaoran Shu, Yanfei Sun · 5 authors
For 6G-empowered IoT, blockchain is widely regarded as a fundamental technique for addressing the security and privacy issues. Nonetheless, the current blockchains suffer from several flaws, especially the low performance and scalability. They seriously hinder the blockchain deployments in 6G-empowered IoT with high concurrency and complexity. To address this problem, we need to better understand blockchains and try to optimize them. However, we still lack a standard tool for comprehensively benchmarking the IoT-oriented blockchains in 6G era. As to blockchain optimization, the current general-purpose strategies can hardly hold efficiency all the time due to the heterogeneity of 6G-empowered IoT. In this paper, we present a novel pipeline for facilitating the green IoT-oriented blockchains in 6G era, called “fine-grained benchmarking + targeted optimization.” Specifically, we first design a benchmarking framework which realizes the whole workflow of data acquisition, log parsing, and metric visualization, offering quantitative blockchain performance reports. Moreover, our framework provides ten metrics divided into four dimensions, leading blockchain benchmarking to the fine-grained level. Based on the acquired insights, we further present the concept of targeted optimization, i.e., directly designing optimization strategies based on the metrics that perform poorly in benchmarking. To better illustrate this pipeline, we take IOTA, the most potential IoT-oriented blockchain in 6G era, as a case study. We observe two defects of IOTA, i.e., low power efficiency and slow ledger synchronization. Following our pipeline, we design two targeted optimization mechanisms, namely Proof-of-Resource Efficiency and Dynamic Local Snapshot Protocol. Extensive experiments demonstrate that our pipeline can maximize the optimization efficiency, successfully addressing the issues hindering IOTA. Last but not least, we emphasize that the proposed pipeline can also be applied by other IoT-oriented blockchains in the 6G era.
Retail energy markets are increasingly consumer-oriented, thanks to a growing number of energy plans offered by a plethora of energy suppliers, retailers and intermediaries. To maximize the benefits of competitive retail energy markets, group purchasing is an emerging paradigm that aggregates consumers' purchasing power by coordinating switch decisions to specific energy providers for discounted energy plans. Traditionally, group purchasing is mediated by a trusted third-party, which suffers from the lack of privacy and transparency. In this paper, we introduce a novel paradigm of decentralized privacy-preserving group purchasing, empowered by privacy-preserving blockchain and secure multi-party computation, to enable users to form a coalition for coordinated switch decisions in a decentralized manner, without a trusted third-party. The coordinated switch decisions are determined by a competitive online algorithm, based on users' private consumption data and current energy plan tariffs. Remarkably, no private user consumption data will be revealed to others in the online decision-making process, which is carried out in a transparently verifiable manner to eliminate frauds from dishonest users and supports fair mutual compensations by sharing the switching costs to incentivize group purchasing. We implemented our decentralized group purchasing solution as a smart contract on Solidity-supported blockchain platform (e.g., Ethereum), and provide extensive empirical evaluation.
Web3 is the most hyped concept from 2020 to date, greatly motivating the prosperity of the Internet of Value and Metaverse. However, no solid evidence stipulates the exact definition, criterion, or standard in the sense of such a buzzword. To fill the gap, we aim to clarify the term in this work. We narrow down the connotation of Web3 by separating it from high-level controversy argues and, instead, focusing on its protocol, architecture, and evaluation from the perspective of blockchain fields. Specifically, we have identified all potential architectural design types and evaluated each of them by employing the scenario-based architecture evaluation method. The evaluation shows that existing applications are neither secure nor adoptable as claimed. Meanwhile, we also discuss opportunities and challenges surrounding the Web3 space and answer several prevailing questions from communities. A primary result is that Web3 still relies on traditional internet infrastructure, not as independent as advocated. This report, as of June 2022, provides the first strict research on Web3 in the view of blockchain. We hope that this work would provide a guide for the development of future Web3 services.
Blockchain is a developing technology that can provide users with such advantages as decentralization, data security, and transparency of transactions. Blockchain has many applications, one of them is the decentralized finance (DeFi) industry. DeFi is a huge aggregator of various financial blockchain protocols. At the moment, the total value locked in these protocols reaches USD 82 billion. Every day more and more new users come to DeFi with their investments. The concept of decentralized finance involves the creation of a single ecosystem of many blockchains that interact with each other. The problem of combining and interacting blockchains becomes crucial to enable DeFi. In this paper, we look at the essence of the DeFi industry, the possibilities of overcoming the problem of cross-blockchain interaction, present our approach to solving this problem with the Wish Swap platform, which, in particular, provides improved fault-tolerance for cross-chain interaction by using multiple backend nodes and multisignatures. We analyze the results of the proposed solution and demonstrate how a prototype pre-sale application can be created based on the proposed concept.
R. G. Jahn, Oliver Kraft, Marcel Klaes, Dennis Schmid · 6 authors
As power systems continuously become increasingly volatile and complex systems, conventional market designs turn inefficient, unnecessarily exclusive, and also agnostic towards grid and system capacities. While partial solutions to this already exist, the emerging distributed ledger technologies open up the field to holistic solutions. This work outlines the shortcomings of nowadays market designs, provides a conceptual design improvement along with its technical requirements and finally presents a high-level implementation based on IBM’s blockchain project Hyperledger Fabric.
Recently, multi-agent systems (MASs) have received attention due to the consideration of distributed optimization and control in blockchain (BC) based energy trading applications. However, due to the dynamic behavior of uncertain and random variables, the coordination and control of MAS are still challenging to attain resilience and dynamicity. Traditional trust systems, which rely on access control and cryptography, cannot deal with dynamic behavior of agents. Furthermore, they are inefficient in addressing the computational overhead of cryptographic primitives. To overcome these limitations, this work proposes a BC-based trusted suite (TS) for MAS to handle privacy and anonymity issues during energy trading in a smart grid (SG). In this work, three objectives are simultaneously achieved: trust, cooperation, and confidentiality. Firstly, the proposed trust system is employed to perform trust credibility of agents based on trust deformation, coherence, and stability. The credibility evaluation is used to determine the dynamic behavior of agents and to detect dishonest agents in the system. Secondly, a tri-tit-for-tat (TTFT) repeated game approach is used to improve the cooperation among agents. The proposed strategy is more forgiving than the existing Di-TFT (DTFT) and TFT techniques. It motivates scammers and deceptive agents to regain their trust by cooperating in three consecutive rounds of a game. Furthermore a proof-of-cooperation (PoC) consensus mechanism is introduced to facilitate agent cooperation in block creation and validation. Thirdly, the publicly verifiable secret sharing (PVSS) technique is introduced to preserve the privacy of the agents. Unlike VSS, PVSS provides the immunity against different types of security threats. Where, the dealer agent maintained the trust, while the verification of the dealer and combiner is maintained within agent-to-agent cooperation. Simulation results show that the devised BTS model is superior to the existing benchmark model such as fuzzy logic trust (FLT) in terms of detecting the cheating and deceptive behavior of agents in the system. Besides, the devised TTFT allows cheating agents to effectively regain the trust if they cooperate thrice in a row as compared to the existing DTFT and TFT strategies. Furthermore, This study analyzes two trust-related attacks: bad-mouthing and on-off. Analysis shows that the proposed system is protected from trust related attacks.
With the ever-increasing applications of the Internet of Things (IoT), e.g., smart homes, smart cities, smart factories, etc., data security and device trustworthiness become the major concerns. Although blockchain contributes to achieve the data traceability and fault tolerance, the huge resource consumption and limited performance severely restrict its deployments in IoT. Moreover, the unique features of IoT, such as mobility, resource constraints, and security vulnerabilities, create even greater difficulties for blockchain running. Observing the lack of blockchain analyzing tools for IoT, we intend to provide a fair means with standard metrics for better understanding IoT-oriented blockchain. In this article, we present BCmaster, a blockchain analyzing and monitoring framework focusing on IoT scenarios. Based on the detailed modeling of blockchain-assisted IoT, we propose a novel metric set named 5-D quantitative metric framework, which can conduct the comprehensive blockchain analysis from five dimensions. Moreover, we design a modular architecture for BCmaster, wherein the interaction requests (IRs)-based data parser ensures a high system compatibility and the synchronous metric visualizer facilitates the real-time blockchain monitoring in IoT. Extensive evaluations in a real IoT environment demonstrate the validity of BCmaster and explore the performance of four IoT-oriented blockchain systems. Last but not least, we discuss the ways to customize IoT-oriented blockchain with the help of BCmaster.
Abstract Large penetration of various types of distributed energy resources and new requirements in electricity markets, have facilitated creation of sophisticated distributed energy resource aggregation systems for providing grid services. Aggregators such as Virtual Power Plants enable participation of small‐ and medium‐scale distributed energy resources in electricity markets, interacting with grid operators to collectively provide ancillary power and energy services. These interactions between grid operator, Virtual Power Plants operator and distributed energy resources are complex both in terms of contractual agreements and provision of services. On all layers, accurate tracking of distributed energy resource usage and execution of contracts is required for establishing trust between transacting participants. Digitalisation and automation of processes such as control of distributed energy resources, verification and payouts for services will add value for solving complexity of dealing with multiple parties in a Virtual Power Plants aggregation model. The authors present a blockchain‐integrated Virtual Power Plants system that enables full automation of distributed energy resource controls through smart contracts, digital trust between participants and immediate payouts for services. Effectiveness of the developed blockchain mechanism is demonstrated on a pilot Virtual Power Plants system comprising distributed energy storage systems, renewables, EV charging stations and loads with a total size of 1.8 MWs. Additionally, we propose a new mechanism for managing renewable energy curtailments through blockchain.
Robert Antwi, James Dzisi Gadze, Eric Tutu Tchao, Axel Sikora · 10 authors
The increase of the Internet of Things (IoT) calls for secure solutions for industrial applications. The security of IoT can be potentially improved by blockchain. However, blockchain technology suffers scalability issues which hinders integration with IoT. Solutions to blockchain’s scalability issues, such as minimizing the computational complexity of consensus algorithms or blockchain storage requirements, have received attention. However, to realize the full potential of blockchain in IoT, the inefficiencies of its inter-peer communication must also be addressed. For example, blockchain uses a flooding technique to share blocks, resulting in duplicates and inefficient bandwidth usage. Moreover, blockchain peers use a random neighbor selection (RNS) technique to decide on other peers with whom to exchange blockchain data. As a result, the peer-to-peer (P2P) topology formation limits the effective achievable throughput. This paper provides a survey on the state-of-the-art network structures and communication mechanisms used in blockchain and establishes the need for network-based optimization. Additionally, it discusses the blockchain architecture and its layers categorizes existing literature into the layers and provides a survey on the state-of-the-art optimization frameworks, analyzing their effectiveness and ability to scale. Finally, this paper presents recommendations for future work.
IoT blockchain suffers heavy performance issues because of the massive transactions generated by various IoT nodes. By dividing nodes into different shards, sharding can produce blocks in parallel and hence improve the throughput of the blockchain system. Unlike the traditional blockchain system, IoT blockchain mainly consists of smart devices and the transactions are usually generated from the real world, such as the sensor data, photos taken by cameras, and so on. In IoT blockchain, closer nodes usually share a lower network latency and the transactions they generate are more related. Therefore, location-based sharding is an effective approach to improve the performance of IoT blockchain. Traditionally, IoT nodes are di-vided into different shards based on geographical locations or the connected edge server. However, the key challenge of sharding in IoT blockchain is how to guarantee the equality of shards division as to the unpredictable distribution and the dynamic behavior of IoT nodes. On one hand, shards can not be pre-divided because we can not predict the number or the distribution of the IoT nodes. On the other hand, nodes continuously joining or quitting shards will also break the equality of the shards division. In this paper, we propose Fission, a sharding mechanism designed for IoT blockchain. Fission divide shards based on the Voronoi diagram without any preknowledge about the nodes distribution, and support dynamic, autonomous sharding adjustment based on distributed Delaunay Triangulation. In addition, Fission uses a new diffusion-based consensus algorithm to achieve the linear scalability of throughput. The experimental results show that Fission can construct and adjust shards at a very low cost and can execute in a decentralized manner. The throughput can reach 1900tps in 500 nodes with only 5M bps bandwidth, and can scale linearly as the nodes increase.
Ting Cai, Wuhui Chen, Kostas E. Psannis, Sotirios K. Goudos · 7 authors
In the future sharing economy, billions of underutilized IoT devices will be deployed to enable a powerful and large-scale sharing market that produces economic, environmental, and social benefits. Given the fact that communications in numerous IoT devices through wireless links are unreliable, blockchain technology, as a promising solution, has emerged to achieve reliable and secure sharing services in a decentralized manner. However, applying blockchain in large-scale wireless networks confronts scalability challenges. This motivates us to propose a real-time, trusted data interactive, and fine-grained transaction supportable sharing framework, the core of which is a novel two-layer scaling blockchain design. In the on-chain layer, sharing-oriented sharding is employed to enable secure and efficient processing of macro-transactions on the chain. In the off-chain layer, cross-zone off-chain channels are set up to provide real-time sharing transactions with high-frequency micro-trading scenarios. Finally, a proof-of-concept case study of electric vehicle sharing data is implemented with experimental results to demonstrate the feasibility of our framework.
In blockchain, ensuring integrity of data when updating distributed ledgers is a challenging and very fundamental process. Most of blockchain networks use Merkle tree to verify the authenticity of data received from other peers on the network. However, creating Merkle tree for each block in the network and composing Merkle branch for every transaction verification request are time-consuming process requiring heavy computations. Moreover, sending these data through the network generates a lot of traffic. Therefore, we proposed an updated mechanism that uses incremental hash chain with probabilistic filter to verify block data, provide a proof of data integrity and efficiently update blockchain light nodes. In this article, we prove that our model provides better performance and less required computations than Merkle tree while maintaining the same security level.
A blockchain is a distributed and decentralized database that allows users to securely store and exchange data without requiring the intervention of a third party. Information, called transactions, is collected in blocks, which are then linked together via cryptographic processes in an irreversible way. The registry has served as a historical record of all actions taken by participants in the network since its launch. An increase in the number of transactions, leading to a considerable increase in the size of the primary blockchains, making them more difficult to maintain, perhaps discouraging certain nodes from storing the entire blockchain and therefore weakening decentralization. In this study, we introduce the low-storage node, a new type of node that stores chunks of blocks rather than whole blocks and is encoded with an erasure code. A low-storage node recovers the initial block by downloading and decoding a enough encoded fragments from other nodes in the network. This strategy has the advantage of allowing certain nodes to keep a reduced version of the blockchain while contributing to its decentralization. This simplifies the scaling of blockchains, which is one of the main flaws of the technology. BlockStock is a complete system that allows nodes to rent out its additional storage space to others. The main innovation is the use of blockchain-based smart contracts that enable frequent, automated and secure payments based on proofs of recovery provided by storage servers.
With a large market capitalization, Ethereum is one of the most famous blockchain platforms supporting smart contracts nowadays. To better understand Ethereum, previous researches have performed numerous analyses on Ethereum via complex network theory, while many of them merely focus on a single perspective of scale or time series. This motivates us to investigate the evolution of Ethereum from a local point of view. We concentrate our study on some key accounts labeled by the community. Then we crawl and extract their transaction subgraphs, and conduct an analysis based on several basic network properties consisting of network scale and triadic tendencies by sliding window. Furthermore, we provide an insight into the local structure of these subgraphs by counting the graphlets induced from the label nodes. Subsequently, we observe diverse similarities and differences between various label nodes in the changing trend and subgraph patterns in the locality of Ethereum networks. The results and findings from this study may help us to understand the activity of Ethereum more comprehensively.
Abstract Blockchain technology has been recognised as a promising technology for supporting Peer‐to‐Peer (P2P) energy trading—an emerging paradigm in which energy trading is performed directly between end energy customers. The state‐of‐the‐art blockchain designs for P2P energy trading can only support less compute‐intensive energy trading tasks and/or rely on the set up of a long challenge time to ensure correctness of transactions, which restricts the systems' scalability and applicability in the diverse P2P energy trading applications. This paper proposes a new dual‐blockchain system for P2P energy trading. The system consists of a primary blockchain and a secondary blockchain. The primary blockchain is mainly responsible for storing the data of P2P energy trading transactions while the compute‐intensive tasks (e.g. pricing and transaction verification) are executed in the secondary blockchain. An Improved Optimistic Rollup (IOR) mechanism is proposed to facilitate the co‐operation of the dual blockchains. Through a specific ‘executor‐validator’ mechanism and a group of specific smart contracts with different functions, the IOR mechanism can effectively accommodate the dual blockchains to execute the P2P energy trading transactions in a computational efficient manner while ensuring the correctness and security of the transactions. A prototype of the proposed system is implemented on Fisco Bcos and Alibaba Cloud and comprehensive simulations are conducted to validate the proposed system.
Liping Tao, Yang Lu, Ding Xu, Yuqi Fan · 5 authors
Blockchain is a viable solution to provide data integrity for the enormous volume of 5G IoT social data, while we need to break through the throughput bottleneck of blockchain. Sharding is a promising technology to solve the problem of low throughput in blockchains. However, cross-shard communication hinders the effective improvement of blockchain throughput. Therefore, it is critical to reasonably allocate transactions to different shards to improve blockchain throughput. Existing research on blockchain sharding mainly focuses on shards formation, configuration, and consensus, while ignoring the negative impact of cross-shard communication on blockchain throughput. Aiming to maximize the throughput of transaction processing, we study how to allocate blockchain transactions to shards in this paper. We propose an Associated Transaction assignment algorithm based on Closest Fit (ATCF). ATCF classifies associated transactions into transaction groups which are then assigned to different shards in the non-ascending order of transaction group sizes periodically. Within each epoch, ATCF tries to select a shard that can handle all the transactions for each transaction group. If there are multiple such shards, ATCF selects the shard with the remaining processing capacity closest to the number of transactions in the transaction group. When no such shard exists, ATCF chooses the shard with the largest remaining processing capacity for the transaction group. The transaction groups that cannot be completely processed within the current epoch will be allocated in the subsequent epochs. We prove that ATCF is a 2-approximation algorithm for the associated transaction assignment problem. Simulation results show that ATCF can effectively improve the blockchain throughput and reduce the number of cross-shard transactions.
He Xue, Dajiang Chen, Ning Zhang, Hong‐Ning Dai · 5 authors
As an important technology to ensure data security, consistency, traceability, etc., blockchain has been increasingly used in Internet of Things (IoT) applications. The integration of blockchain and edge computing can further improve the resource utilization in terms of network, computing, storage, and security. This paper aims to present a survey on the integration of blockchain and edge computing. In particular, we first give an overview of blockchain and edge computing. We then present a general architecture of an integration of blockchain and edge computing system. We next study how to utilize blockchain to benefit edge computing, as well as how to use edge computing to benefit blockchain. We also discuss the issues brought by the integration of blockchain and edge computing system and solutions from perspectives of resource management, joint optimization, data management, computation offloading and security mechanism. Finally, we analyze and summarize the existing challenges posed by the integration of blockchain and edge computing system and the potential solutions in the future.
The use of blockchain in regulatory ecosystems is a promising approach to address challenges of compliance among mutually untrusted entities. In this work, we consider applications of blockchain technologies in telecom regulations. In particular, we address growing concerns around Unsolicited Commercial Communication (UCC aka. spam) sent through text messages (SMS) and phone calls in India. Despite several regulatory measures taken to curb the menace of spam it continues to be a nuisance to subscribers while posing challenges to telecom operators and regulators alike. In this paper, we present a consortium blockchain based architecture to address the problem of UCC in India. Our solution improves subscriber experiences, improves the efficiency of regulatory processes while also positively impacting all stakeholders in the telecom ecosystem. Unlike previous approaches to the problem of UCC, which are all ex-post, our approach to adherence to the regulations is ex-ante. The proposal described in this paper is a primary contributor to the revision of regulations concerning UCC and spam by the Telecom Regulatory Authority of India (TRAI). The new regulations published in July 2018 were first of a kind in the world and amended the 2010 Telecom Commercial Communication Customer Preference Regulation (TCCCPR), through mandating the use of a blockchain/distributed ledgers in addressing the UCC problem. In this paper, we provide a holistic account of of the projects' evolution from (1) its design and strategy, to (2) regulatory and policy action, (3) country wide implementation and deployment, and (4) evaluation and impact of the work.