Clack is Joint Field Chief Editor for the research journal Frontiers in Blockchain. Recent publications from Frontiers in Blockchain are given below:


  • Artificial Intelligence for Demystifying Blockchain Technology Challenges: A Survey of Recent Advances

    Artificial Intelligence for Demystifying Blockchain Technology Challenges: A Survey of Recent Advances

    Blockchain technology has gained lots of traction in the past five years due to the innovations introduced in digital currency, the Bitcoin. This technology is powered by distributed ledger technology, which is a distributed database system. It is often renowned for decentralization, anti-attack, and unfalsified attributes making it a top choice in several non-monetary applications. In fact, the problem of privacy and security of the Internet of Things has been undertaken aggressively with Blockchain. Several problems have been identified with blockchain technology such as large delays and lack of support for real-time transaction processing, authorization, node verification, and consensus mechanisms. This article intends to provide a comprehensive survey on the recent advances and solutions to the problems of blockchain technology by leveraging the artificial intelligence approaches. The outcomes of this study will provide valuable information and guidance on the design of Blockchain-based systems to support time-sensitive and real-time specific applications and processes.

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  • Government by Code? Blockchain Applications to Public Sector Governance

    Government by Code? Blockchain Applications to Public Sector Governance

    Studies of blockchain governance can be divided into analyses of the governance of blockchains (such as rules and power dynamics within a given network) and governance by blockchains (such as how blockchains can be implemented to improve self-governance of community-based peer production networks). Less emphasis has been placed on applications of distributed ledgers to public sector governance. Our review clarifies that the decentralization and distributive features that enable blockchains to link up loosely connected private organizations and public agencies to improve efficiency and transparency of government transactions. However, most blockchain applications lack clear advantages over the conventional digital recording of information. In addition, our review highlights that blockchain applications in public sector governance are potentially vast, though in most instances, the existing applications have not extended much beyond limited-scale pilots. We conclude with a call for the construction of indexes of public sector implementations of blockchains, as none yet exist, as well as for additional research to understand why governments have not deployed blockchains more widely.

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  • Paillier Cryptosystem Based ChainNode for Secure Electronic Voting

    Paillier Cryptosystem Based ChainNode for Secure Electronic Voting

    Blockchain is a distributed and decentralized ledger of transactions that are linked together cryptographically leading to immutability and tamper-resistance, thereby ensuring the integrity of data. Due to the ability of blockchain to guarantee the integrity of data, it has found wide-range adoption in electronic voting (e-voting) systems in recent years, this is in a bid to prevent manipulation of votes. However, due to the distributed nature of the blockchain, opportunities arise for privacy intrusion of the data being secured. The translation of this privacy flaw in blockchain to e-voting systems is the possibility of violation of the privacy of the electorates. Consequently, in a bid to achieve integrity and privacy of votes in e-voting, this study presents the use of an open-source blockchain system, coupled with a privacy-oriented cryptosystem known as the Paillier cryptosystem, towards addressing the privacy concerns of the blockchain. The performance of the system was evaluated and a transaction throughput of 1424 tps was obtained for ten thousand simulated ballot transactions. Further evaluation was carried out on the system, by increasing the number of system transactions. This showed that the mining time of the blockchain increased by an average factor of 0.18 s for every thousand increases in the number of transactions. Also, the response time of the system to a range of user actions was evaluated over an increasing number of voters. Results obtained showed that the response time of the system for vote casting operations increased by an average of 0.33 min per thousand voters while for vote tallying there was an increase in response time by an average of 0.848 min per thousand voters. The scientific value of this study is the development of an integrity and privacy-preserving e-voting system consisting of an open-source nodechain coupled with a privacy-oriented cryptosystem known as the Paillier cryptosystem following the security requirements of e-voting systems. The proposed system addresses the issue of integrity in e-voting while still maintaining the privacy of the electorates.

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  • Event-Based Supply Chain Network Modeling: Blockchain for Good Coffee

    Event-Based Supply Chain Network Modeling: Blockchain for Good Coffee

    Blockchain and distributed ledger technology (BC/DLT) provides distributed databases with decentralized governance, tamper-proof recording, high availability and non-copyable digital assets, which have made it a natural technological basis for supply chain management. In this paper, we introduce REALISTIC, a novel event-based modeling framework for supply chain networks (SCNs) that includes production processes. It extends McCarty’s Resources-Events-Agents (REA) accounting model with secure transformations, which, across the entire SCN, guarantee that certified output resources cannot be digitally produced ex nihilo, but require certified input resources of at least the same amount as what is produced. This generalizes the no-double-spend guarantee of current BC/DLT to (digital twins of) physical resources and their production. Authenticated human or robotic Internet of Things (IoT) actors digitally sign and cryptographically commit to the veracity of real-world events on an immutable database, without having to take responsibility for their aggregate consequences. User-specifiable interpretations, corresponding to queries and analytical functions in database systems, provide auditable aggregate information computed from recorded events across the entire SCN. This includes fine-grained and trustworthy tracing of final products through multiple stages of production processes, semi-finished products, quality certifications and transportation all the way back to their raw materials. We present a case study for an end-to-end coffee supply chain that tracks fine-grained and detailed information from a farmer’s coffee cherries to retail coffee bags, involving all its actors. Our model handles product provenance; auditable sustainability, quality and trade information; production processes from parchment via green to roasted coffee; product quality tests; farmer certifications; and transportation across the entire coffee supply chain. It is based on field work involving farmers, cooperatives, processors, traders, importers, and a major roasting company stretching from Colombia to Scandinavia. Its REALISTIC-based modeling is the foundation for the design of our prototype implementation, which includes Ethereum blockchain code, RDBMS-based server code and a web app client. Their source code is publicly available on GitHub.

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  • Editorial: Emerging Technologies and Blockchain in Action: Applications in Supply Chain Management and Energy
  • Community Impact on a Cryptocurrency: Twitter Comparison Example Between Dogecoin and Litecoin

    Community Impact on a Cryptocurrency: Twitter Comparison Example Between Dogecoin and Litecoin

    Context: The third generation of cryptocurrencies gathers cryptocurrencies that are as diverse as the market is big (e.g., Dogecoin or Litecoin). While Dogecoin is seen as a memecoin, the other gathers a very different category of investors. To our knowledge, no study has independently assessed the crypto community’s economical impact on these cryptocurrencies. Furthermore, various methodological possibilities exist to forecast cryptocurrency price—mainly coming from online communities.

    Method: Our study has retrospectively studied (from 01/01/2015 to 03/11/2021)—using open access data—the association strength (using normalized mutual information) and the linear correlation (using Pearson’s correlation) between Twitter activity and cryptocurrency economical attributes. In addition, we have computed different models (ADF, ARIMA, and Interpretable MultiVvariable Long Short-Term Memory recurrent neural network) that forecast past price values and assessed their precision.

    Findings and conclusions: While the average Dogecoin transaction value is impacted by tweets, tweets are impacted by Litecoin transactions number and average Litecoin transaction value. Tweet number is impacted by Dogecoin whale behavior, but no significant relationship was found between Litecoin whales and tweets. The forecasting error resulting from our ARIMA (0,0,0) models was 0.08% (with Litecoin) and 0.22% (with Dogecoin). Therefore, those are just the beginning of scientific findings that may lead to building a trading robot based on these results. However, in itself, this study is only for academic discussion, and conclusions need to be drawn by further research. The authors cannot be liable if any financial investment is made based on its conclusions.

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  • Financing Orphan Drugs Through a Blockchain-Supported Insurance Model

    Financing Orphan Drugs Through a Blockchain-Supported Insurance Model

    The cost of treatment for rare diseases is notoriously high imposing threats to the global healthcare system. Existing market-based tools for orphan drugs are not designed to reduce drug prices and could be hampered by adverse selection. We propose an alternative insurance mechanism, Massive Group Insurance (MGI), which aims at reducing the prices of orphan drugs through offering separate Intellectual Property Right (IPR) Fees to the drug company from an MGI Agency, which will collect insurance premiums from each country on each orphan drug that the country wants all its citizens to enjoy access to. The premiums will be calculated so as to ensure that the drug company will collect a profit no smaller than what it enjoys under the traditional model. The plan uses the group insurance concept and will generate a significant increase in drug use. Blockchain technology is used to facilitate authentication and effective IPR payments and ensure data security and low administrative cost. This model can potentially be extended to other categories of expensive drugs and vaccines.

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  • Editorial: Economic and Business Implications of Blockchain Technology
  • Review of Automated Vulnerability Analysis of Smart Contracts on Ethereum

    Review of Automated Vulnerability Analysis of Smart Contracts on Ethereum

    Programs on public blockchains often handle valuable assets, making them attractive targets for attack. At the same time, it is challenging to design correct blockchain applications. Checking code for potential vulnerabilities is a viable option to increase trust. Therefore, numerous methods and tools have been proposed with the intention to support developers and analysts in detecting code vulnerabilities. Moreover, publications keep emerging with different focus, scope, and quality, making it difficult to keep up with the field and to identify relevant trends. Thus, regular reviews are essential to keep pace with the varied developments in a structured manner. Regarding blockchain programs, Ethereum is the platform most widely used and best documented. Moreover, applications based on Ethereum are entrusted with billions of USD. Like on similar blockchains, they are subject to numerous attacks and losses due to vulnerabilities that exist at all levels of the ecosystem. Countermeasures are in great demand. In this work, we perform a systematic literature review (SLR) to assess the state of the art regarding automated vulnerability analysis of smart contracts on Ethereum with a focus on classifications of vulnerabilities, detection methods, security analysis tools, and benchmarks for the assessment of tools. Our initial search of the major on-line libraries yields more than 1,300 publications. For the review, we apply a clear strategy and protocol to assure consequent, comprehensive, and reproducible documentation and results. After collecting the initial results, cleaning up references, removing duplicates and applying the inclusion and exclusion criteria, we retain 303 publications that include 214 primary studies, 70 surveys and 19 SLRs. For quality appraisal, we assess their intrinsic quality (derived from the reputation of the publication venue) as well as their contextual quality (determined by rating predefined criteria). For about 200 publications with at least a medium score, we extract the vulnerabilities, methods, and tools addressed, among other data. In a second step, we synthesize and structure the data into a classification of both the smart contract weaknesses and the analysis methods. Furthermore, we give an overview of tools and benchmarks used to evaluate tools. Finally, we provide a detailed discussion.

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  • A Comprehensive Study of the Trends and Analysis of Distributed Ledger Technology and Blockchain Technology in the Healthcare Industry

    A Comprehensive Study of the Trends and Analysis of Distributed Ledger Technology and Blockchain Technology in the Healthcare Industry

    In today’s scenario, it is essential for the healthcare sector to focus on balancing patient care records with information relevant to completeness, accessibility, and privacy concerns. Advancements in information technology and health infrastructure exponentially bolster transformative changes in the healthcare industry. Incorporation of blockchain along with distributed ledger technology (DLT) owes the potentiality to cater to the interoperability restraints in health IT systems and enables medical researchers, healthcare entities, and healthcare providers to share electronic health data in a secured and well-mannered system. In addition to these, such technologies also propose and offer latest models for health statistics exchange by making the records more secure and efficient. However, successful implementation of blockchain technology and DLT necessitates efficient infrastructure, connectivity, and other factors. Hence, there poses to be several challenges restraining the mainstream usage of blockchain technology in the healthcare sector. The article illustrates different generations of blockchain, issues in healthcare data, and network structures as well as the solutions offered by the sector to cater to such problems. In addition to these, the article also emphasizes on the different application areas of blockchain and DLT in healthcare infrastructure. This article further discusses latest trends and factors driving the need for the incorporation of blockchain and distributed ledger technology in the healthcare sector and the future scenario for the same.

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Christopher D. Clack
Department of Computer Science
UCL
Gower Street
London
WC1E 6BT

 clack@cs.ucl.ac.uk