Blockchain technology and its applications are gaining popularity day by day. It is a ground-breaking technology that allows users to communicate without the need of a trusted middleman. A smart contract (self-executable code) is deployed on the blockchain and auto executes due to a triggering condition. In a no-trust contracting environment, smart contracts can establish trust among parties. Terms and conditions embedded in smart contracts will be imposed immediately when specified criteria have been fulfilled. Due to this, the malicious assailants have a special interest in smart contracts. Blockchains are immutable means if some transaction is deployed or recorded on the blockchain, it becomes unalterable. Thus, smart contracts must be analyzed to ensure zero security vulnerabilities or flaws before deploying the same on the blockchain because a single vulnerability can lead to the loss of millions. For analyzing the security vulnerabilities of smart contracts, various analysis tools have been developed to create safe and secure smart contracts. This paper presents a systematic review on Ethereum smart contracts analysis tools. Initially, these tools are categorized into static and dynamic analysis tools. Thereafter, different sources code analysis techniques are studied such as taint analysis, symbolic execution, and fuzzing techniques. In total, 86 security analysis tools developed for Ethereum blockchain smart contract are analyzed regardless of tool type and analysis approach. Finally, the paper highlights some challenges and future recommendations in the field of Ethereum smart contracts.
Blockchain is a revolutionary technology that enables users to communicate in a trust-less manner. It revolutionizes the modes of business between organizations without the need for a trusted third party. It is a distributed ledger technology based on a decentralized peer-to-peer (P2P) network. It enables users to store data globally on thousands of computers in an immutable format and empowers users to deploy small pieces of programs known as smart contracts. The blockchain-based smart contract enables auto enforcement of the agreed terms between two untrusted parties. There are several security vulnerabilities in Ethereum blockchain-based smart contracts, due to which sometimes it does not behave as intended. Because a smart contract can hold millions of dollars as cryptocurrency, so these security vulnerabilities can lead to disastrous losses. In this paper, a systematic review of the security vulnerabilities in the Ethereum blockchain is presented. The main objective is to discuss Ethereum smart contract security vulnerabilities, detection tools, real life attacks and preventive mechanisms. Comparisons are drawn among the Ethereum smart contract analysis tools by considering various features. From the extensive depth review, various issues associated with the Ethereum blockchain-based smart contract are highlighted. Finally, various future directions are also discussed in the field of the Ethereum blockchain-based smart contract that can help the researchers to set the directions for future research in this domain.
Sanal Kripto Para kavramı Bitcoin ile birlikte 2009 yılında dikkat çekmeye başlamış ve özellikle 2013 yılındaki fiyat artışı ile popülaritesi artmıştır. Sanal Kripto Para birimlerinin ilki ve öncüsü olan Bitcoin ile 2. En büyük piyasa değerine sahip olan Ethereum tasarımsal yapıları ve amaçları bakımından birbirlerinden oldukça farklıdır. Sanal bir para birimi olması için tasarlanan Bitcoin ile üzerinde akıllı kontratlar çalışmasına olanak vermek için tasarlanan Ethereum birçok alanda olduğu gibi iktisat alanında da oldukça dikkat çekmiş ve literatürde birçok çalışmaya konu olmuştur. Bu çalışmanın amacı Türkiye GSYH’sı, M2 Tanımı ile para arzı ve tüketici güven endeksinin Bitcoin ve Ethereum fiyatına olan etkilerini karşılaştırmalı olarak tahmin etmektir. Bu amaçla, Bitcoin ve Etherum’un Türk Lirası cinsinden fiyatlarını bağımlı değişken alan iki farklı model kurulmuştur. Kurulan modeller, Ocak 2016 ile Aralık 2020 dönemini kapsayan aylık veriler kullanılarak, zaman serisi analizi kapsamında, Johansen Eşbütünleşme Testi ve Tam Uyarlanmış En Küçük Kareler Yöntemi (FMOLS) kullanılarak uzun dönemde sınanmıştır. Yapılan analizin sonucunda hem Bitcoin hem de Ethereum’un Türk lirası cinsinden fiyatları, GSYH ve tüketici güven endeksi ile pozitif ilişkili, M2 para arzı ile negatif ilişkili bulunmuştur. Çalışmanın bulgularından bir diğeri ise toplam piyasa değeri Bitcoin’e göre daha düşük olan Ethereum’un tüm değişkenlerden daha çok etkilendiğidir. Elde edilen sonuçlar bu çalışmanın türetildiği Yüksek Lisans Tezindeki bulgular ile örtüşmekte ve birbirini desteklemektedir.
Xiaoyang Shi, Hang Xiao, Weifeng Liu, Xi Chen · 7 authors
The distributed consensus mechanism is the backbone of the rapidly developing blockchain network. Blockchain platforms consume vast amounts of electricity based on the current consensus mechanism of Proof-of-Work (PoW). Here, we point out a different consensus mechanism named Proof-of-Stake (PoS) that can eliminate the extensive energy consumption of the current PoW-based blockchain. We comprehensively elucidate the current and projected energy consumption and carbon footprint of the PoW- and PoS-based Bitcoin and Ethereum blockchain platforms. The model of energy consumption of PoS-based Ethereum blockchain can lead the way toward the prediction of other PoS-based blockchain technologies in the future. With the widespread adoption of blockchain technology, if the current PoW mechanism continues to be employed, the carbon footprint of Bitcoin and Ethereum will push the global temperature above 1.5 °C in this century. However, a PoS-based blockchain can reduce the carbon footprint by 99% compared to the PoW mechanism. The small amount of carbon footprint from PoS-based blockchain could make blockchain an attractive technology in a carbon-constrained future. The study sheds light on the urgency of developing the PoS mechanism to solve the current sustainability problem of blockchain.
This paper focuses on the political genealogy of one of the most promising and influential IT technologies of our time: the blockchain (or distributed registry). We point at important commonalities between the principles of blockchain projects and models of republican governance. In contrast to techno-anarchist and democratic ideas, the republican genealogy of blockchain has so far failed to attract the attention of researchers. After examining the basic technical properties and ideological images of blockchain, we explore how the four main principles of classical republicanism (personal freedom and autonomy of the individual; civic virtues; common good; recognition of great causes) are realized in influential blockchain projects — Bitcoin (developed by the pseudonymous Satoshi Nakamoto) and Ethereum (developed by Vitalik Buterin). The functioning of blockchain nodes is supported by a community of miners, who are free, but at the same time agree to act for the development of a common thing. What the republic and the blockchain have in common is that it is impossible to have a community without cooperative action. At the same time, blockchain is a vivid illustration of Bruno Latour's argument on the role of non-humans in social relations: his code seeks to replace untrustworthy humans with rule-acting nodes, and to create a cryptographic society where untrustworthy human relations are replaced by computers' relations. This article is an invitation to begin a discussion of the political ideas that are embedded in new technologies and the models of governance that are mobilized through them, often without proper reflection on the nature of such ideas by their creators.
The blockchain as the tool was invented together with the Bitcoin and evolving. Despite the fact that new blockchains appeared, like Ethereum and other, the first one was not explored enough from the perspective of understanding dependencies between its elements. Mathematical and cryptographic dependencies are well described in the scientific literature, but dependencies exploration and description in relation to its economical usage of it is still missing. The blockchain structure and mechanics provide that transaction registered within the blockchain are not free for the final user. The transaction price in the Blockchain exists. This transaction price can be decisive for the implementation of a project using blockchain. Understanding factors, which affect this price forming helps to understand frames, when usage of the blockchain is effective. Taking into account all above mentioned, one of the targets of this article is to analyze the life cycle of transactions in the blockchain and determine the factors that have a significant impact on the formation of the transaction price in the Bitcoin Blockchain. From the other hand blockchain assumed as the competitor or even “killer” of the traditional payment systems. There is the list of elements, which should be taken in account comparing both approaches for the transaction execution. This list includes comparing deficits and advantages of both systems, like security issues, transaction speed issues and so on. From this perspective based on the comparing the transactional price forming in both systems, author assess the prospects for using transactions in the Blockchain in comparing with the traditional payment systems.
Bu çalışma 2011 yılından itibaren temel olarak “belirsizlik” ve “ekonomi” anahtar kelimelerini içeren tweetlerin baz alınarak oluşturulduğu Twitter Bazlı Belirsizlik Endeksinin, son yılların gözde yatırım araçlarından olan kripto paraların volatilitesine etkisini incelemeyi amaçlamaktadır. Piyasa değeri en yüksek, Binance, Bitcoin, Cardano, Ethereum, Ripple ve Tether kripto paralar 18/01/2018- 11/07/2021 dönemi için günlük verilerle ARCH-GARCH ailesi modelleri ile incelenmiştir. Çalışmada öncelikle ortalama denklemi oluşturulan modellerin ARCH-GARCH modellerine uygunluğu sınanmış ve incelenen dönemde Bitcoin ve Ethereum için ARCH etkisinin olmadığı ancak Binance, Cardano, Ripple ve Tether için volatilite modellerinin kullanımının uygun olduğu bulgusu elde edilmiştir. Binance için GARCH (1,1), Cardano için GARCH-M (1,1), Ripple için ARCH (2) modeli volatiliteyi en iyi yakalayan model olarak seçilmiştir. Twitter Bazlı Belirsizlik Endeksinin bu modellerin hepsinde istatistiki olarak anlamlı ve pozitif bir etkiye sahip olduğu tespit edilmiştir. Bu sonuçlara göre bir sosyal medya platformu olan Twitter’da yer alan belirsizlik ve ekonomi içerikli tweetlerin kripto varlıkların volatilitesini etkilediğini söylemek mümkündür.
Data sharing is a crucial step in the research community to make the most of the prior effort. Platforms for sharing data currently in use rely on trustworthy third parties (TTP). Such systems lack immutability, security, transparency, and trust because of TTP’s involvement. In order to address these problems, the proposed system approaches an Interplanetary File System (IPFS)-based blockchain-based secure data sharing platform. The user uploads a data file to the IPFS server, which is subsequently split up into several secret shares. By carrying out the access responsibilities that the user has specified in the smart contract, the suggested scheme accomplishes security and access control. This scenario combines encryption, Ethereum blockchain technology, decentralized storage, and incentive systems. Solidity smart contracts are created and deployed on a local Ethereum test network in order to carry out the suggested scenario. Transparency, Security, Access control, Owner authenticity, and Data quality are all achieved by the suggested plan.
Blockchain is one of the technologies provided by the global distribution of computing power. Simply put, the blockchain is the digital ledger in which transactions are recorded. It all started with a desire to see a new form of security system for transferring confidential files. It aims to achieve many goals like decreasing the process time for transferring files to the other party, and reducing the overall expenses as the files are only transferred across the blockchain network with no need for the files to be uploaded and downloaded to the drive. More effective applications have the ability to share files via the technology of Blockchain. The great challenge is to build a private blockchain environment to send files and distribute them securely between parties, such as military institutions and others. In this paper, a private blockchain is built to overcome the side of the security through a secured file-sharing network. This private Blockchain can be utilized at various institutions. A high scale of security is obtained through using an important algorithm that takes into consideration a critical part of the field of cryptography to robustly encrypt the files. The latter ensures that no individual except for the receiver has the ability to access the files. As well, a sufficient speed was obtained when transferring the files, as compared to Ethereum with FTP. Finally, smart contracts have been designed to suit the transfer of files between nodes.
Sanjib Kumar Nayak, Sarat Chandra Nayak, Subhranginee Das
Artificial neural networks (ANNs) are suitable procedures for predicting financial time series (FTS). Cryptocurrencies are good investment assets; therefore, the effective prediction of cryptocurrencies has become a trending area of research. Capturing inherent uncertainties associated with cryptocurrency FTS with conventional methods is difficult. Though ANNs are the better alternative, fixing the optimal parameters of ANNs is a tedious job. This article develops a hybrid ANN through Rao algorithm (RA + ANN) for the effective prediction of six popular cryptocurrencies such as Bitcoin, Litecoin, Ethereum, CMC 200, Tether, and Ripple. Six comparative models such as GA + ANN, PSO + ANN, MLP, SVM, LSE, and ARIMA are developed and trained in a similar way. All these models are evaluated through the mean absolute percentage of error (MAPE) and average relative variance (ARV) metrics. It is found that the proposed RA + ANN generated the lowest MAPE and ARV values, statistically different as compared with existing methods mentioned above, and hence can be recommended as a potential financial instrument for predicting cryptocurrencies.
The objective of this paper is to assess the performances of dimensionality reduction techniques to establish a link between cryptocurrencies. We have focused our analysis on the two most traded cryptocurrencies: Bitcoin and Ethereum. To perform our analysis, we took log returns and added some covariates to build our data set. We first introduced the pearson correlation coefficient in order to have a preliminary assessment of the link between Bitcoin and Ethereum. We then reduced the dimension of our data set using canonical correlation analysis and principal component analysis. After performing an analysis of the links between Bitcoin and Ethereum with both statistical techniques, we measured their performance on forecasting Ethereum returns with Bitcoin s features.
This paper focuses on the technology impact via Blockchain to change consumer behavior in the digital art industry. The paper objectives are three folds: first, analyze the impact of Ethereum in selling digital artwork and on the bank world. Second, investigate the effects of Non-Fungible Token on the art industry. Third, highlight how people can sell their artworks, tweets, or even memes for thousands of dollars. Fourth, explain the effect of Ethereum in creating value for artwork and why a meme that includes nothing unique to be sold for an unbelievable price? The paper provides insights on the future of the digital arts industry and the rational behavior of the developers, artists, and even customers, as the three parties shape the business of the NFL’s success. It reflects on the investment behavior in digital arts and the importance of a secure long-term investment for a niche segment that seeks to satisfy their need of acquiring unique products. The paper serves as a guide for digital art and focuses on how AI applications create profitable markets.
Francesco Buccafurri, Gianluca Lax, Lorenzo Musarella, Antonia Russo
The need for a flexible, dynamic, and decentralized energy market has rapidly grown in recent years. As a matter of fact, Industry 4.0 and Smart Grids are pursuing a path of automation of operations to insure all the steps among consumers and producers are getting closer. This leads towards solutions that exploit the paradigm of public blockchain, which represents the best platform to design flat and liquid markets for which providing trust and accountability to mutual interactions becomes crucial. On the other hand, one of the risks arising in this situation is that personal information is exposed to the network, with intolerable threats to privacy. In this paper, we propose a solution for energy trading, based on the blockchain Ethereum and Smart Contracts.The solution aims to be a concrete proposal to satisfy the needs of energy trading in smart grids, including the important feature that no information about the identity of the peers of the network is disclosed in advance.
Ilhaam A. Omar, Raja Jayaraman, Mazin Debe, Haya R. Hasan · 6 authors
Information sharing is essential for coordination and stakeholder integration and is crucial to achieving sustainable supply chain operations. Furthermore, improved information sharing assists retailers by reducing the time spent looking for alternative suppliers to meet the unexpected demand surge during pandemics. Recent advances in networking and distributed ledger technologies have enabled secure, improved information communication and broader connectivity. However, due to system interoperability, information quality, confidentiality, and trust, information cannot be exchanged seamlessly, resulting in the inefficiency of managing supply chain operations. In this paper, we propose a blockchain-based inventory sharing approach based on smart contracts using a private Ethereum network to link suppliers and retailers. Our approach combines blockchain technology with decentralized storage to increase transparency, trust, and security of supply chain transactions. We present a generalized mechanism for secure information sharing that includes comprehensive algorithms to capture supply chain stakeholder interactions that enhance trust among participating entities. The smart contract was developed and validated using the Remix IDE, and the code is made publicly available on Github. We analyze the solution for various security vulnerabilities and provide a detailed cost analysis for various stakeholder transactions in the supply chain. Our solution demonstrates that a blockchain-based approach reduces inefficiencies, is economical, commercially viable, and provides improved information connectivity among supply chain stakeholders in a trusted and secure way.
Behkish Nassirzadeh, Huaiying Sun, Sebastian Bănescu, Vijay Ganesh
In recent years we have witnessed a dramatic increase in the adoption and application of smart contracts in a variety of contexts such as decentralized finance, supply chain management, and identity management. However, a critical stumbling block to the further adoption of smart contracts is their security. A particularly widespread class of security vulnerabilities that afflicts Ethereum smart contracts is the gas limit denial of service(DoS) on a contract via unbounded operations. These vulnerabilities result in a failed transaction with an out-of-gas error and are often present in contracts containing loops whose bounds are affected by end-user input. Note that such vulnerabilities differ from gas limit DoS on the network via block stuffing. Therefore, we present Gas Gauge, a tool aimed at detecting Out-of-Gas DoS vulnerabilities in Ethereum smart contracts. Gas Gauge consists of three major components: the Detection, Identification, and Correction Phases. The Detection Phase consists of an accurate static analysis approach that finds and summarizes all the loops in a smart contract. The Identification Phase uses a white-box fuzzing approach to generate a set of inputs that causes the contract to run out of gas. The Correction Phase uses static analysis and run-time verification to predict the maximum loop bounds consistent with allowable gas usage and suggest appropriate repairs to the user of the tool. Each part of the tool can be used separately for different purposes or all together to detect, identify and help repair the contracts vulnerable to Out-of-Gas DoS vulnerabilities. Gas Gauge was tested on 1,000 real-world solidity smart contracts deployed on the Ethereum Mainnet. The results were compared to seven state-of-the-art static and symbolic tools, and it was empirically demonstrated that Gas Gauge is far more effective than competing state-of-the-art tools.
The Internet of things (IoT) is the key enabler of the smart systems used in many areas, from agriculture to aviation, industrial automation to autonomous vehicles. Most IoT deployments employ cost-efficient lightweight devices with limited resources (e.g., bandwidth, energy, storage). Although an IoT network must be built in its simplest form, engineers include more sophisticated devices like gateways and servers to provide web-based services and benefit from cloud systems. So, although the nodes can be widely distributed geographically or topologically, the system becomes centralized, which causes bottlenecks and single-points-of-failure. Furthermore, providing data integrity, nonrepudiation, and event management becomes tricky. In most IoT scenarios, data usually flow from sensors to storage and processing units, whereas event-driven commands and triggers flow from these units to actuators, if any. Therefore, an attacker who gained access to parts of the centralized systems may leak, alter, or remove critical data and may exploit event handling features. This is where blockchain technology can be extremely useful. Using a decentralized ledger as the data storage unit provides integrity, immutability, and nonrepudiation for any IoT deployment. And a customized smart contract lets the IoT deployment benefit from decentralized and immutable (i.e. nonmanipulatable) event management features, too. Further, decentralization provides resilience against availability attacks to a large extent. With this motivation, we introduced a novel IoT architecture that incorporates an Ethereum-based private (Quorum) blockchain running a unique ad-hoc smart contract and a message queue telemetry transport (MQTT) based communication scheme between sensor and actuator nodes. The scheme, the ledger, and the smart contract have also been implemented with several nodes, a broker, and a server all on a PC using Docker containers, where the server was running a forest fire risk detection algorithm as the use case scenario. The proof-of-concept successfully validates the abovesaid functionality, scalability, and efficiency for the given IoT scenario (and some others). Moreover, performance tests showed that an instance of the system with 1000 nodes could stably process and record incoming (sensor) data up to 12.5 transactions per second (TPS) and distribute commands up to 4 TPS, whereas higher TPS is achievable depending on the network conditions and tolerance to losses. The scheme was shown to have polynomial message and time complexity.
Rodrigo Dutra Garcia, Gowri Ramachandran, Raja Jurdak, Jó Ueyama
Real-world applications in healthcare and supply chain domains produce, exchange, and share data in a multi-stakeholder environment. Data owners want to control their data and privacy in such settings. On the other hand, data consumers demand methods to understand when, how, and who produced the data. These requirements necessitate data governance frameworks that guarantee data provenance, privacy protection, and consent management. We introduce a decentralized data governance framework based on blockchain technology and proxy re-encryption to let data owners control and track their data through privacy-enhancing and consent management mechanisms. Besides, our framework allows the data consumers to understand data lineage through a blockchain-based provenance mechanism. We have used Digital e-prescription as the use case since it has multiple stakeholders and sensitive data while enabling the medical fraternity to manage patients' prescription data, involving patients as data owners, doctors and pharmacists as data consumers. Our proof-of-concept implementation and evaluation results based on CosmWasm, Ethereum, and pyUmbral PRE show that the proposed decentralized system guarantees transparency, privacy, and trust with minimal overhead.
Bu makalenin amacı kriptopara birimleri olarak da adlandırılan merkezi olmayan para birimleri olan Bitcoin Cash, Ethereum, Litecoin ve Ripple arasındaki ilişkilerin ortaya çıkarılmasıdır. Çalışmada üzerinde çalışılan dönem 03.08.2017 – 17.03.2020 tarihleri arasıdır. Çalışmada birim kök testi olarak Augmented Dickey-Fuller (ADF) testi uygulanarak serilerin durağan olduğu düzeyler saptanmış ve aralarındaki nedensellik ilişkisi Granger nedensellik testi ile sınanmıştır. Seriler arasındaki ilişkilerin yönü ve büyüklüğü, vektör otoregresif (VAR) model tekniğiyle belirlenmeye çalışılmıştır. Ayrıca, etki-tepki analizleri ve varyans ayrıştırma analizleri yapılarak serilerin standart sapmasında meydana gelen değişimin dönem bazında % kaçının diğer değişkenler tarafından açıklandığı ortaya konmuştur.
Abstract Early public blockchains provided low transaction throughputs in the range of 7–30 transactions per second. With the emergence of permissioned and proof-of-stake-based blockchains, transaction throughputs are expected to rise drastically to thousands per second. Blockchain transactions form directed graphs. With high transaction throughputs and growing blockchain adoption by banks, businesses and customers in general, the number of edges in transaction graphs will dynamically grow to billions. An analysis of large-scale transaction graphs is needed for tracing fraudulent activities on blockchains. This chapter will cover topics such as distributed graph data structures, the use of message passing libraries, and parallel graph algorithms in order to build a scalable transaction graph analysis system. Results from the analysis of the real Ethereum and Bitcoin public blockchain data involving cryptocurrency and ERC20 token transactions will be presented.
E-Donation cloud funding system is an indispensable part of the society. It is a feasible method to assist any donors in any part of the world. Donors require fully secured system where there all information will not be hacked by hackers. As Web 3.0 is the third generation of internet services that can make the system fully secured which is distributed decentralized and semantic. It means with the Artificial Intelligence (AI); it does not have a centralized control node. Public Blockchain- a decentralized, distributed ledger technology - is the implementation of Web 3.0 that technology will be used to develop this system which would be an open source. This paper will look into Ethereum Blockchain technology and recognize the fundamental support it provides for Web 3.0 framework.
We execute a comparative analysis of machine learning models for the time-series forecasting of the sign of next-day cryptocurrency returns. We begin by compiling a proprietary dataset that encompasses a wide array of potential cryptocurrency valuation factors (price trends, liquidity, volatility, network, production, investor attention), subsequently identifying and evaluating the most significant factors. We apply eight machine learning models to the dataset, utilizing them as classifiers to predict the sign of next day price returns for the three largest cryptocurrencies by market capitalization: bitcoin, ethereum, and ripple. We show that the most significant valuation factors for cryptocurrency returns are price trend variables, seven and thirty-day reversal, to be specific. We conclude that support vector machines result in the most accurate classifications for all three cryptocurrencies. Additionally, we find that boosted models like AdaBoost and XGBoost have the poorest classification accuracy. At length, we construct a probability-based trading strategy that secures either a daily long or short position on one of the three examined cryptocurrencies. Ultimately, the strategy yields a Sharpe of 2.8 and a cumulative log return of 3.72. On average, the strategy’s log returns outperformed standalone investments in all three cryptocurrencies by a factor of 5.64, and Sharpe ratios more than threefold.
Hafiz Humza Saeed, Abdullah Bin Masood, Hassaan Khaliq Qureshi
Smart cities utilize digital technologies for the improvement of its services’ quality and performance by reducing resources’ cost and consumption, with a commitment of action and efficiency to its citizens. The increased urban migration has led to many problems in cities, such as traffic congestion, waste management, noise pollution, energy consumption, air pollution, etc., as nowadays COVID-19 pandemic has seized the whole world. So, it is necessary to carry out its standard operating procedures (SOPs), including less human interaction. Thus, technology plays a vital role via Internet-of-Things (IoT) based systems. In this paper, a lightweight security mechanism (LSM) is proposed to enrich the IoT based systems. Blockchain technology is integrated, and its completely decentralized peer-to-peer (P2P) technology enables the users’ authentication and authorizes legitimate procedures. The IoT based management system is developed to monitor some of the aforementioned problems and solve solid waste, air, and noise monitoring systems. The Ethereum blockchain is used to implement a smart contract based framework for the system’s security and access control. The evaluation of performance of the LSM demonstrates that it is an efficient and lightweight tool in terms of cost, resources, and computation and superior over related security studies.
The article is devoted to the study of theoretical and practical aspects of the risks that accompany the activities of economic actors in the cryptocurrency market (both mining and trading) at the micro and macroeconomic level at the beginning of the third decade of the XXI century. The risks associated with the functioning of economic entities in the market of cryptocurrency coins and such risks are the following: lack of legal regulation on the cryptocurrency market and insurance of owners of assets stored on crypto wallets; use of malware in order to access assets rotating on the cryptocurrency market; hacking attacks on cryptocurrency wallets and exchanges in order to steal cryptoassets; loss of assets deposited into accounts of cryptocurrency exchanges in case of bank-ruptcy or closure of these exchanges; loss of the password used to access the crypto wallet; loss of a secret personal PIN code, which is the key to access funds deposited into the crypto wallet at the exchange and used to transfer assets (cryptocurrencies or fiat currencies) to other crypto wallets or a bank card; erroneous transaction due to one number or letter mistake when transferring from one crypto wallet to another or error (when entering bank card number), when transferring funds from crypto wallet to bank card, a mistake of one or more numbers is possible and funds will be transferred to the wrong addressee, in both cases it is impos-sible to cancel the transaction and funds are lost irrevocably; significant volatility in the value of cryptocurrencies, because of which an investor can go bankrupt. It was revealed that the functioning of the cryptocurrency market is also associated with risks to the national economy and security: monetary policy (reduction of control over monetary circulation due to the replacement of national fiat currency with cryptocurrency coins and the loss of the central bank monopoly on the emission of money and reducing the country's income from seigniorage due to mining cryptocurrencies), financial stability (because of the threat of the outflow of deposits from the banking system and replacing them with investments in cryptocurrencies, the possibility of replacing traditional banking, as well as the possibility of avoiding taxation and shadowing the economy) and national security. It has been proven that the intensive activity of an economic entity associated with mining, trading, investing or other economic activities in the cryptocurrency market requires significant theoretical and practical training of the individual and patience and faith in the future of cryptocurrency market activity because of the probability of losing savings invested in cryptocurrencies or investments.Keywords: risk, cryptocurrency, cryptocurrency market, crypto coin, crypto wallet, Bitcoin, Ethereum, cyberattack. Статтю присвячено дослідженню ризиків, які супроводжують діяльність ринку криптовалют, як майнінгу, так і трейдингу. Охарактеризовано ризики, з якими пов’язане функціонування ринку криптовалют, і такими ризиками є: відсутність правового регулювання та страхування власників криптогаманців; використання шкідливих програм та здійснення хакерських атак на криптогаманці і біржі криптовалют; утрата активів, розміщених на рахунках криптовалютних бірж, у разі банкрутства чи закриття цих бірж; утрата паролю від криптогаманця чи втрата секретного персонального PINкоду, що є ключем доступу до коштів, розміщених на криптогаманці на біржі; помилкова транзакція (через помилку на одну цифру чи букву) під час переказу з одного криптогаманця до іншого (також під час переказу грошових коштів із криптогаманця на банківську картку можлива помилка на одну чи кілька цифр, і кошти будуть переказані не тому адресанту, якому вони передбачалися); значна волатильність вартості криптовалют. Виявлено, що функціонування ринку криптовалют пов’язане з ризиками для національної економіки: монетарної політики, фі-нансової стабільності, інвестиційної та банківської діяльності. Доведено, що активна діяльність економічного суб’єкта, пов’язана з майнінгом, торгівлею, інвестуванням чи іншою економічною діяльністю на ринку криптовалют, вимагає значної теоретичної і практичної підготовки особи через імовірність утратити заощадження, вкладені у криптоферми чи інвестиції.Ключові слова: ризик, криптовалюта, крипторинок, криптомонета, криптогаманець, Bitcoin, Ethereum, хакерська атака.
Cryptocurrencies often tend to maintain a publically accessible ledger of all transactions. This open nature of the transactional ledger allows us to gain macroeconomic insight into the USD 1 Trillion crypto economy. In this paper, we explore the free market-based economy of eight major cryptocurrencies: Bitcoin, Ethereum, Bitcoin Cash, Dash, Litecoin, ZCash, Dogecoin, and Ethereum Classic. We specifically focus on the aspect of wealth distribution within these cryptocurrencies as understanding wealth concentration allows us to highlight potential information security implications associated with wealth concentration. We also draw a parallel between the crypto economies and real-world economies. To adequately address these two points, we devise a generic econometric analysis schema for cryptocurrencies. Through this schema, we report on two primary econometric measures: Gini value and Nakamoto Index which report on wealth inequality and 51% wealth concentration respectively. Our analysis reports that, despite the heavy emphasis on decentralization in cryptocurrencies, the wealth distribution remains in-line with the real-world economies, with the exception of Dash. We also report that 3 of the observed cryptocurrencies (Dogecoin, ZCash, and Ethereum Classic) violate the honest majority assumption with less than 100 participants controlling over 51% wealth in the ecosystem, potentially indicating a security threat. This suggests that the free-market fundamentalism doctrine may be inadequate in countering wealth inequality within a crypto-economic context: Algorithmically driven free-market implementation of these cryptocurrencies may eventually lead to wealth inequality similar to those observed in real-world economies.