Consensus mechanisms are at the core of any Distributed Ledger Technology. They define how transactions are validated and verified, how the network resolves conflicts and protects against malicious intent, and how multiple devices on a distributed network with no central authority arrive at the same global view of the ledger. Experience with the consensus mechanisms employed in popular blockchain platforms have warranted years of research into more scalable and energy-efficient consensus mechanisms for a green society using constrained devices. Most of the “high-security” consensus mechanisms require the use of computational resources which are simply not available to devices with a constrained nature. Hence, the presence and activity of these devices do not contribute to the security of the ledger, irrespective of how numerous they are on the network. In this paper, we propose a novel consensus scheme, fully dependent on WiFi technology, suitable for constrained devices. Whilst in traditional Blockchain consensus mechanisms, constrained devices do not add to the security of the ledger, the security of our consensus mechanism increases with the number of connected devices.
Scalability and security problems of the centralized architecture models in cyberphysical systems have great potential to be solved by novel blockchain based distributed models.A decentralized energy trading system takes advantage of various sources and effectively coordinates the energy to ensure optimal utilization of the available resources. It achieves that goal by managing physical, social and business infrastructures using technologies such as Internet of Things (IoT), cloud computing and network systems. Addressing the importance of blockchain-enabled energy trading in the context of cyberphysical systems, this article provides a thorough overview of the P2P energy trading and the utilization of blockchain to enhance the efficiency and the overall performance including the degree of decentralization, scalability and the security of the systems. Three blockchain based energy trading models have been proposed to overcome the technical challenges and market barriers for better adoption of this disruptive technology.
Mohammad Tahir, Mohamed Hadi Habaebi, Mohammad Dabbagh, Amna Mughees · 6 authors
Until now, every evolution of communication standard was driven by the need for providing high-speed connectivity to the end-user. However, 5G marks a radical shift from this focus as 5G and beyond networks are being designed to be future-proof by catering to diverse requirements of several use cases. These requirements include Ultra-Reliable Low Latency Communications, Massive Machine-Type Communications and Enhanced Mobile Broadband. To realize such features in 5G and beyond, there is a need to rethink how current cellular networks are deployed because designing new radio access technologies and utilizing the new spectrum are not enough. Several technologies, such as software-defined networking, network function virtualization, machine learning and cloud computing, are being integrated into the 5G networks to fulfil the need for diverse requirements. These technologies, however, give rise to several challenges associated with decentralization, transparency, interoperability, privacy and security. To address these issues, Blockchain has emerged as a potential solution due to its capabilities such as transparency, data encryption, auditability, immutability and distributed architecture. In this paper, we review the state-of-art application of Blockchain in 5G network and explore how it can facilitate enabling technologies of 5G and beyond to enable various services at the front-haul, edge and the core. Based on the review, we present a taxonomy of Blockchain application in 5G networks and discuss several issues that can be solved using Blockchain integration. We then present various field-trials and Proof of concept that are using Blockchain to address the challenges faced in the current 5G deployment. Finally, we discuss various challenges that need to be addressed to realize the full potential of Blockchain in beyond 5G networks. The survey presents a broad range of ideas related to Blockchain integration in 5G and beyond networks that address issues such as interoperability, security, mobility, resource allocation, resource sharing and management, energy efficiency and other desirable features.
Hui Li, Lishuang Pei, Dan Liao, Song Chen · 6 authors
Vehicular Ad Hoc Network (VANET) is an important foundation of intelligent transportation system and is widely used in traffic management, automatic driving, and road optimization. With the gradual popularization and further development of VANET, a large amount of VANET data has been produced. However, it poses huge challenges to the security and privacy when using VANET data provides services for users. In this paper, combining the technologies of blockchain and ciphertext-based attribute encryption (CP-ABE), we propose a fine-grained access control scheme for VANET data based on blockchain (FADB). In FADB, we employ the blockchain to replace the third-party service providers for user identity management and data storage. And different VANET data access rights can be established according to user attribute. By improving the CP-ABE, the lightweight VANET devices can outsource complex encryption and decryption operations to powerful RSUs and further improve the efficiency of data access. Final, we carry out a series of simulation tests and security analysis, proving that the FADB can provide effective data security and low performance overhead.
The ability to store and share digital data offers benefits that the digitization of information has become a growing trend but has raised questions about the security of personal data. There have been countless high-profile hacks and personal information leaks. Furthermore users don’t (and shouldn’t) always trust an external server of a third party to store their personal data. Blockchain tries to offer a compelling solution to the problem of combining accessibility with privacy and security. Records can be held securely, using end-to-end encryption, and yet openly authenticated so that data can still be trusted as reliable. This project goes deeper in this solution thanks to an innovative idea and development of a new kind of blockchain non fungible token specifically created to store and manage digital identities and sensible data. It has the potential to resolve issues blockchain alone was starting to approach and improves security, privacy and accessibility.
Privacy-focused crypto-currencies, such as Zcash or Monero, aim to provide strong cryptographic guarantees for transaction confidentiality and unlinkability.In this paper, we describe side-channel attacks that let remote adversaries bypass these protections.We present a general class of timing side-channel and traffic-analysis attacks on receiver privacy.These attacks enable an active remote adversary to identify the (secret) payee of any transaction in Zcash or Monero.The attacks violate the privacy goals of these crypto-currencies by exploiting side-channel information leaked by the implementation of different system components.Specifically, we show that a remote party can link all transactions that send funds to a user, by measuring the response time of that user's P2P node to certain requests.The timing differences are large enough that the attacks can be mounted remotely over a WAN.We responsibly disclosed the issues to the affected projects, and they have patched the vulnerabilities.We further study the impact of timing side-channels on the zero-knowledge proof systems used in these cryptocurrencies.We observe that in Zcash's implementation, the time to generate a zero-knowledge proof depends on secret transaction data, and in particular on the amount of transacted funds.Hence, an adversary capable of measuring proof generation time could break transaction confidentiality, despite the proof system's zero-knowledge property.Our attacks highlight the dangers of side-channel leakage in anonymous crypto-currencies, and the need to systematically protect them against such attacks.
Despite the antidiscrimination frameworks contained in the constitutional and statutory protections for the right to vote, access to the American ballot box is generally perceived as heavily contested. More precisely, many right-to-vote advocates (and their popular supporters) believe that the right to vote is in a crisis of exclusion so extreme that it represents a resurgence of Jim Crow racial exclusion from the franchise. Advocates for election integrity initiatives and their supporters claim that because of impending threats by “illegal voters” who will distort election results, initiatives like voter identification laws, proof of citizenship laws, and voter purges are necessary, else the integrity of the electoral process will be destroyed.\nThese views are diametrically opposed and suggest that what we know about the status of the right to vote itself is at stake. One view is premised on seeing the ecosystem of democracy as replicating intersecting racial and class-driven exclusion. The other sees the world as dominated by the threat of illegal voters and supposes that the threat of voter fraud is an existential threat to American election integrity. That such divergent views exist on exactly what the crisis of voting rights is, suggests that there is a fault in the way we obtain and order our knowledge regarding American democratic practices. Our knowledge about how to understand the right to vote is a contested issue. ...\nIn the years since this argument, the meme of voter fraud has been amplified17 and augmented in the far more dense (and self-selecting) political ecosystem that is Internet-driven American political discourse. The meme has served as justification for not only voting rights policy changes, like voter identification laws, but also to connect the threat of so-called “illegal voters” to issues ranging from proof of citizenship requirements, to felon disenfranchisement, the census, and the Electoral College. The evolved, weaponized, amplified voter fraud meme has created an epistemic crisis—a crisis of how we know—for the law of democracy.\nThis short Article will consider this crisis. The Article will argue that the meme has evolved providing an “alternative facts” explanation for voting threats to the creation of a worldview that underscores an ideology of exclusion of those unworthy to exercise the franchise by expanding the narrative of the persons and communities who pose a threat to American elections. The Article will turn next to explaining my claims about the voter fraud meme and connect that to how it consolidates political power. It will then examine how the meme has evolved and amplified in recent years and consider its ramifications for upcoming election cycles. And then the Article will end by considering the larger, epistemological threat that such meme-driven thinking poses to our democracy, and how the law of democracy is ill-suited to address such problems. But to adequately explain this point, I must first draw on my prior research to explain the sense in which I mean a “meme” and how it relates to voter fraud talk.
The article is aimed at disclosing the issue of financial support for the construction, reconstruction, repair and maintenance of motor roads in the context of implementation of budget decentralization and decentralization of road management. The article specifies the steps taken towards implementation of decentralization in the sphere of road infrastructure of Ukraine and the introduction of budget decentralization: distribution of functions and powers in the road sphere at the subregional level of management and the updated mechanism of financing the road industry. Both the dynamics of formation and distribution of the State Road Fund and the status of distribution of subvention on the streets and roads of settlements are analyzed. The vision of the main risks of financial support for the maintenance of streets and roads of communal property in settlements in 2021 is disclosed. The directions of improvement of the system of financial support for the construction, reconstruction, repair and maintenance of motor roads are proposed, including in particular: the need to deepen diversification of sources of formation of the State Road Fund; consolidation of the proper guaranteed part of the State Road Fund’s costs for the maintenance of streets and roads of communal property in settlements; balancing the expenditure load and financial support for the implementation of road projects; increasing the level of transparency of decision-making in the distribution of financial resources intended for the construction, reconstruction, major, ongoing repair of motor roads.
The article is aimed at studying the essential component of decentralization and budget revenues; determining the main results of the implemented reform of budget decentralization in Ukraine; analyzing the current situation of own revenues of local budgets. The following general scientific methods were used in the research process: theoretical generalization, comparison and grouping – to determine the essence of the concepts of «budget revenues», «decentralization» and disclosure of components of budget revenues; analysis – when considering own revenues of local budgets for 2014–2020 and the structure of incomes in the revenues of local budgets for January – July 2020; system approach – in the formation and disclosure of the essences of the main stages of the reform of budget decentralization in Ukraine. The views of various scientists on the concepts of «budget revenues» and «decentralization» are examined. It is determined that budget revenues are an aggregate of financial relations that participate in the process of distribution of part of GDP in order to form targeted cash funds at the level of the State and local self-government bodies, designed to finance their own functions and obligations defined in accordance with the current legislation. The main components of budget revenues are determined and their classification is provided. The main stages of the budget decentralization reform in Ukraine are defined and systematized, their detailed characterizations are provided. The analysis of own revenues of local budgets for 2014–2020 and revenues in local budget revenues for January – July 2020 was carried out, during which it was determined that local taxes, despite the introduced budget decentralization, comprise only about 30% in the structure of incomes in the revenues of the general fund of local budgets, while in some countries of the European Union this figure reaches 50–60%. Practical steps towards further implementation of the budget decentralization reform for local self-government bodies are proposed.
A blockchain is a digitized, decentralized, public ledger of all cryptocurrency transactions. The blockchain is transforming industries by enabling innovative business practices. Its revolutionary power has permeated areas such as bank-ing, financing, trading, manufacturing, supply chain management, healthcare, and government. Blockchain and the Internet of Things (BIOT) apply the us-age of blockchain in the inter-IOT communication system, therefore, security and privacy factors are achievable. The integration of blockchain technology and IoT creates modern decentralized systems. The BIOT models can be ap-plied by various industries including e-commerce to promote decentralization, scalability, and security. This research calls for innovative and advanced re-search on Blockchain and recommendation systems. We aim at building a se-cure and trust-based system using the advantages of blockchain-supported secure multiparty computation by adding smart contracts with the main blockchain protocol. Combining the recommendation systems and blockchain technology allows online activities to be more secure and private. A system is constructed for enterprises to collaboratively create a secure database and host a steadily updated model using smart contract systems. Learning case studies include a model to recommend movies to users. The accuracy of models is evaluated by an incentive mechanism that offers a fully trust-based recom-mendation system with acceptable performance.
Open access
Blockchain Technology Applications and Security
IoT and Edge/Fog Computing
Advanced Steganography and Watermarking Techniques
Bruno Bernardo, Raphaël Cauderlier, Basile Pesin, Julien Tesson
Tezos is a smart-contract blockchain. Tezos smart contracts are written in a low-level stack-based language called Michelson. In this article we present Albert, an intermediate language for Tezos smart contracts which abstracts Michelson stacks as linearly typed records. We also describe its compiler to Michelson, written in Coq, that targets Mi-Cho-Coq, a formal specification of Michelson implemented in Coq.
Smart contracts have the potential to improve many existing transactions and to enable entirely new business models. However, the technology supporting this new method of transacting is complex and the legal framework applying to it is somewhat unclear. Though theorised several decades ago, it was not until the advent of the distributed ledger technology known as blockchain that smart contracts were able to be practically implemented. This paper summarises the concept of smart contracts while providing the background and context of its development. It then distinguishes those smart contracts which are considered legally binding within the scope of US laws from those that may not have legal effect. Next, it provides an in-depth example of an exploitation of smart contracts and explores how the legal reaction to it is inadequate. To reduce the likelihood of future smart contract exploitations and to improve confidence for contracting parties, this article suggests adding explicit smart contract cybersecurity provisions to existing US legal frameworks. Specifically, I propose adapting several of the National Institute of Standards and Technology’s Federal Information Processing Standards to create minimum cybersecurity requirements for all legally binding smart contracts. I also examine the shortcomings of the Computer Fraud and Abuse Act while identifying it as a piece of legislation ripe for reform which, if done adequately, may provide a legal deterrent to would-be cyber hackers of smart contracts.
João Santos Reis, Paul Crocker, Simão Melo de Sousa
This paper introduces Tezla, an intermediate representation of Michelson smart contracts that eases the design of static smart contract analysers. This intermediate representation uses a store and aims to preserve the semantics, flow and resource usage of the original smart contract. This enables properties like gas consumption to be statically verified. We provide an automated decompiler of Michelson smart contracts to Tezla. In order to support our claim about the adequacy of Tezla, we develop a static analyser that takes advantage of the Tezla representation of Michelson smart contracts to prove simple but non-trivial properties.
The study aims at understanding the current scenario of blockchain education and whether it is meeting the increasing demand of blockchain professionals in the job market. In addition, it also provided a comparison between Ethereum and Hyperledger and analyzed the one best suited for better academic curriculum design. By drawing from various sources of data, including journals, articles, reports, the study provided critical insights into the various aspects of a blockchain education. It assesses the existing curriculum on the blockchain that includes courses and programs from various renowned universities and business schools. The study reveals that although the courses are comprehensive in developing theoretical knowledge of the learner, it does not provide the scope for practical skill development. This gap reflects the skill-shortage of blockchain professionals in the job market. To address this, the research also provides some guidelines for developing a comprehensive pedagogical structure using Hyperledger technology. The discussion also highlights the benefits associated with Hyperledger and the way it can foster active learning among the learners. Finally, the researcher also provided the practical and theoretical implications of the study and assessed its limitations directing on the future course of research.
Cryptocurrency markets are highly volatile, with significant and sudden price shifts often influenced by investor sentiment. We demonstrate the significant role of herd behaviour in influencing positive attitudes and subsequent behaviour in cryptocurrency purchasing. Through a survey of 130 active cryptocurrency investors, we empirically examine the factors which influence attitudes and behaviours. Our results indicate that perceived behavioural control, social norms, and propensity to imitate others, a dimension of herd behaviour, strongly influence attitudes towards cryptocurrency behaviour and subsequent behaviours. These findings provide new insights into some of the psychological factors involved in the decision to invest in cryptocurrency and help to understand the unpredictable cryptocurrency market environment.
Romina Torres, Miguel A. Solís, Rodrigo Salas, Aurelio F. Bariviera
Cryptocurrencies have been receiving the sustained attention of investors since 2009. These new investment vehicles are digitally native, meaning that they are traded exclusively on 24/7 digital platforms. Consequently, they offer an excellent scenario to test the Efficient Market Hypothesis, by developing algorithm-based trading strategies. Such strategies aim to beat the market. It has been previously reported that daily returns do not exhibit long range dependence. However, daily volatility in major cryptocurrencies is highly persistent. Therefore, buy/hold/sell decision support systems could be able to capture such market inefficiency. This is especially important for investors interested in periodically trading a set of cryptocurrencies, in order to maximize their wealth. This paper presents a dynamic linguistic decision making approach for building decision models to support cryptocurrency investors in buy/hold/sell decisions. This approach exhibits a good computational performance for obtaining recommendations based on quantitative data. Moreover, this procedure is able to identify some inefficient cryptocurrency behaviors which are not captured by traditional econometric techniques. Our results uncover arbitrage opportunities that outperform buy-and-hold or random strategies.
Xinwen Ni, Taojun Xie, Wolfgang Karl Härdle, Xiaorui Zuo
Abstract Cryptocurrency markets are highly sensitive to regulatory changes, often experiencing sharp price fluctuations in response to new policies and government interventions. Despite this, existing market indices fail to adequately capture the risks associated with regulatory uncertainty. In this paper, we introduce the Cryptocurrency Regulatory Risk Index (CRRIX), a machine learning-based index designed to quantify the impact of regulatory developments on cryptocurrency markets. Our methodology employs Latent Dirichlet Allocation (LDA) to classify policy-related news articles from major cryptocurrency news platforms, providing an objective measure of regulatory risk. We find that the CRRIX exhibits strong synchronicity with VCRIX, a cryptocurrency volatility index, suggesting that regulatory uncertainty plays a significant role in driving market fluctuations. Our results indicate that regulatory risk is a leading factor in market volatility, with major policy shifts triggering significant market movements. The proposed regulatory risk index provides a novel approach to quantifying policy uncertainty in the cryptocurrency sector, offering valuable insights for market participants navigating this rapidly changing environment.
Mazin Debe, Khaled Salah, Muhammad Habib ur Rehman, Davor Svetinović
Fog computing systems are designed to provide localized computation, storage, and communication services in close proximity to the endpoint mobile and IoT devices. Fog service providers typically monetize their service usage via centralized payment mechanisms in unverifiable and non-transparent manner. Therefore, there exists a need for a trust-enabling payment mechanism whereby fog service providers should be incentivized or penalized based upon the continuous feedback from endpoint devices. We propose a decentralized reverse-bidding scheme developed using the key features of blockchain and smart contracts. We develop a solution that allows the users or devices to initiate the bidding process by making a request for services to be provided by nearby public fog nodes, and these fog nodes to make bid offers in return. The proposed scheme ensures that all fog nodes on the network can equally and fairly make offers to win the bid. The bidding process incorporates the automated payments at the end of the service. Our solution is implemented using Ethereum smart contracts. It also integrates a reputation system for fog nodes and imposes a penalty for misbehaving nodes. Our solution is fully decentralized and provides a high level of trust, transparency, and security. In the paper, we present the system architecture, implementation details, and show the correct functionality of the overall proposed solution. In addition, we provide performance, cost, and security analyses of the smart contract code to demonstrate its effectiveness and robustness against major security concerns. The results show that the cost of running the smart contract remained less than three cents with the current Ethereum price (i.e., 183.22 USD/Eth). We have also made our smart contract code publicly available on Github.
Multi-party authorization (MPA) typically involves multiple parties to control and grant access to shared data. MPA is used to solve the insider’s attack problem by ensuring that a single authority or party is not acting alone. Currently, almost all existing implementations of MPA are centralized and fall short in providing logs and events related to provenance of granting permissions in a trusted, secure, immutable, auditable, and decentralized manner. Moreover, for sharing data, proxy re-encryption algorithms are often used to give secure access to encrypted shared data. These schemes and algorithms are also centralized and cannot be trusted. In this paper, we propose a fully decentralized blockchain-based solution in which MPA is implemented using Ethereum smart contracts, and proxy re-encryption algorithms (which are computationally expensive) are implemented using multiple oracles to give access to encrypted shared data stored on a public and decentralized storage platform, such as the Interplanetary File Systems (IPFS). The smart contracts help to validate results based on the majority of encrypted results determined by the oracles. For this, we incorporate reputation mechanisms in the proposed smart contracts to rate the oracles based on their malicious and non-malicious behaviors. We present algorithms along with their full implementation, testing, and validation details. We evaluate the proposed system in terms of security, cost, and generalization to show its reliability and practicality. We make the smart contract source code publicly available on Github.
Christian P. Nielsen, Elias Ribeiro da Silva, Fei Yu
Digital Twins and Blockchain are key elements that when connected allow continuous data acquisition in the factory. As the connection between digital twins and blockchain is rather under-explored, the key contribution of this paper is the conceptual development of a digital twin prototype connected with an Ethereum-based blockchain. The outcome of the paper provides a concept to ensure the unique tokens represent the physical assets without being tampered with by applying digital twin technology. The paper includes a case study focused on Matrix-Structured Manufacturing Systems for Small and Medium-sized Enterprises.