Follow blockchain research across journals, conferences, and preprint repositories.
29,250 results · page 1187 of 1,219
Till Neudecker, Hannes Hartenstein
No abstract is available for this record.
Nashirah Abu Bakar, Sofian Rosbi, Kiyotaka Uzaki
This paper analyses the operation of cryptocurrency system in perspective of Islamic finance. The purpose of this study is to evaluate the cryptocurrency framework whether it is meet the Islamic Finance rule. In addition, this study performed in providing the Islamic minded investor a proper information regarding investment in Bitcoin. Cryptocurrency is a digital currency in which encryption techniques that implement to regulate the generation of units of currency and verify the transfer of funds, operating independently of a central bank. A transaction is a transfer of Bitcoin value that is broadcast to the network and collected into blocks. A transaction typically references previous transaction outputs as new transaction inputs and dedicates all input Bitcoin values to new outputs. This cryptocurrency has no physical form and exists only in the network. Bitcoin also has no intrinsic value in that it is not redeemable for another commodity, namely gold. Then, this study evaluates the framework according to Islamic Finance rule. The bitcoin account holder is anonymous. Therefore, it is difficult to track the real account holder if any suspicious activity occurs. In addition, the value of Bitcoin is unstable because of high volatility. Bitcoin also suffers variance in perceptions of Bitcoin’s store of value and method of value. All of these three conditions contribute to uncertainty in transaction framework of Bitcoin. As a conclusion, Bitcoin transaction is classified as a transaction with high uncertainty (gharar).
Louis Tessler, Tim Byrnes
Bitcoin is a digital currency and payment system based on classical cryptographic technologies which works without a central administrator such as in traditional currencies. It has long been questioned what the impact of quantum computing would be on Bitcoin, and cryptocurrencies in general. Here, we analyse three primary directions that quantum computers might have an impact in: mining, security, and forks. We find that in the near-term the impact of quantum computers appear to be rather small for all three directions. The impact of quantum computers would require considerably larger number of qubits and breakthroughs in quantum algorithms to reverse existing hash functions.
Cristina Pérez‐Solà, Sergi Delgado-Segura, Guillermo Navarro‐Arribas, Jordi Herrera‐Joancomartí
Zero-confirmation transactions, i.e. transactions that have been broadcast but are still pending to be included in the blockchain, have gained attention in order to enable fast payments in Bitcoin, shortening the time for performing payments. Fast payments are desirable in certain scenarios, for instance, when buying in vending machines, fast food restaurants, or withdrawing from an ATM. Despite being quickly propagated through the network, zero-confirmation transactions are not protected against double-spending attacks, since the double-spending protection Bitcoin offers relies on the blockchain and, by definition, such transactions are not yet included in it. In this paper, we propose a double-spending prevention mechanism for Bitcoin zero-confirmation transactions. Our proposal is based on exploiting the flexibility of the Bitcoin scripting language together with a well-known vulnerability of the ECDSA signature scheme to discourage attackers from performing such an attack.
Nashirah Abu Bakar, Sofian Rosbi
The cryptocurrency is a decentralized digital money. Bitcoin is a digital asset designed to work as a medium of exchange using cryptography to secure the transactions, to control the creation of additional units, and to verify the transfer of assets. The objective of this study is to forecast Bitcoin exchange rate in high volatility environment. Methodology implemented in this study is forecasting using autoregressive integrated moving average (ARIMA). This study performed autocorrelation function (ACF) and partial autocorrelation function (PACF) analysis in determining the parameter of ARIMA model. Result shows the first difference of Bitcoin exchange rate is a stationary data series. The forecast model implemented in this study is ARIMA (2, This model shows the value of Rsquared is 0.444432. This value indicates the model explains 44.44% from all the variability of the response data around its mean. The Akaike information criterion is 13.7805. This model is considered a model with good fitness. The error analysis between forecasting value and actual data was performed and mean absolute percentage error for ex-post forecasting is 5.36%. The findings of this study are important to predict the Bitcoin exchange rate in high volatility environment. This information will help investors to predict the future exchange rate of Bitcoin and in the same time volatility need to be monitor closely. This action will help investors to gain better profit and reduce loss in investment decision.
Dirk G. Baur, Daniel Cahill, Keith M. Godfrey, Zhangxin Liu
No abstract is available for this record.
Svetlana Sapuric, Angelika Kokkinaki, Ifigenia Georgiou
This study provides a comparative financial and statistical analysis between the largest and most trad- ed cryptocurrencies. In particular, the exchange rates of Bitcoin, Litecoin, Ripple and Ethereum were collected from August 2010 until May 2017. The raw annualized volatility of cryptocurrencies is compared as well as to fiat currencies and major exchange rates. The results show that Bitcoin is the least volatile cryptocurrency with low correlations with the altcoins, providing possible diversification benefits to cryptocurrency investing. In addition, our results indicate that Bitcoin is the only cryptocurrency that has causality effects on the other cryptocurrencies.
Joseph M. Woodside, Fred K. Augustine, Will Giberson
Purpose: The purpose of this paper is to review the acceptance and future use of blockchain technology. Given the rapid technological changes, this paper focuses on a managerial overview and framework of how the blockchain, including its implementations such as Bitcoin have advanced and how blockchain can be utilized in large-scale, enterprise environments. The paper begins with a technological overview that covers the history of the technology, as well as describing the computational, cryptographic theory that serves as the basis for its notable security features. This paper also covers several key application areas such as finance, accounting, and marketplaces where blockchain technology is seeing major investments from some of the world’s largest organizations. Analysis Methods: Triangulation is utilized for this paper, which combines multiple methodologies, such as qualitative and quantitative methods, as complementary components for improving research study accuracy. The triangulation methods chosen for this paper include a secondary data environment analysis, a text analysis, and financial analysis in order to successfully manage and review the adoption diffusion of innovative technologies like blockchain. The blockchain stands to disrupt many areas of society with the proper application and thus it is important to examine its use with as many viewpoints as possible. Contributions and Conclusion: The contribution this paper describes the potential drivers and drawbacks of blockchain technology in real world applications and highlights the managerial implications of its use. This paper also expands the theoretical contributions for identifying blockchain technology progress on the diffusion of innovation curve. As it stands, the blockchain is within the innovation stage in terms of its application in multi-national enterprises, but with major firms making investments, the blockchain could see growing normalization and acceptance, and at an inflection point akin to the Internet of the 1990s.
Jacob Eberhardt, Stefan Tai
No abstract is available for this record.
Paul Catchlove
Given the rise of interest, opportunities and use of smart contracts, it is important to understand what they are, what technology they rely upon and how they function so that it can be ascertained whether this new technology requires additional regulation, or whether the law as it stands is adequate to administer their usage. This paper will outline two key contentions. First, that smart contracts are well managed by existing contract law principles, however, there are some novel issues associated with this new technology. Second, this paper will suggest a resolution on how to take these novel issues into consideration and ensure they are overcome.
Henry Kim, Marek Laskowski
The blockchain constitutes a technology-based, rather than social or regulation based, means to lower uncertainty about one another in order to exchange value. However, its use may very well also lead to increased complexity resulting from having to subsume work that displaced intermediary institutions had performed. We present our perspective that smart contracts may be used to mitigate this increased complexity. We further posit that smart contracts can be delineated according to complexity: Smart contracts that can be verified objectively without much uncertainty belong in an inter- organizational context; those that cannot be objectively verified belong in an intra- organizational context. We state that smart contracts that implement a formal (e.g. mathematical or simulation) model are especially beneficial for both contexts: They can be used to express and enforce inter-organizational agreements, and their basis in a common formalism may ensure effective evaluation and comparison between different intra-organizational contracts. Finally, we present a case study of our perspective by describing Intellichain, which implements formal, agent-based simulation model as a smart contract to provide epidemiological decision support.
G Jaccard
This paper gives an overview on smart contracts and assess their legal relevance. The first part, explains the notion of smart contract and provides simple examples of it. In the second part, we propose a legal analysis of smart contract. First, we explore how smart contracts can be relevant in the eyes of the law. Then we differentiate and assess smart contract with regards to their types. And finally, we look at chosen problematic of smart legal contracts.
Jeremy Sklaroff
Smart contracts" are decentralized agreements built in computer code and stored on a blockchain.Proponents imagine a future where commerce takes place exclusively using smart contracts, avoiding the high costs of contract drafting, judicial intervention, opportunistic behavior, and the inherent ambiguities of written language.These decentralized code-only contracts are part of a decades-long quest to eliminate supposed inefficiencies in traditional written agreements.Electronic data interchange (EDI), a contracting technology from the 1970s, was designed with the same goal and garnered similar fanfare.Commentators at the time imagined a revolution in the way firms transacted and a full shift away from anything resembling a paper contract.Ultimately EDI failed to achieve these goals-it empowered, rather than circumvented, human decisionmakers along with their "inefficient" way of forming agreements.In doing so, EDI successfully reduced some transaction costs while preserving efficient forms of contractual flexibility.Smart contracts are indeed more technologically sophisticated than EDI.Smart contract scripting languages offer a broader range of operations and greater scalability.Smart contracts are capable of seamlessly integrating with the operational and financial systems at the core of modern firms, whereas EDI transactions occurred in very early digital environments that required human intermediaries.
Zhu, John, Xiwei Xu, Ingo Weber, An Binh Tran · 9 authors
No abstract is available for this record.
Mattias Scherer
The blockchain technology started as the innovation that powered the cryptocurrency Bitcoin. But in recent years, leaders in finance, banking, and many more companies has given this new innovation more attention than ever before. They seek a new technology to replace their system which are often inefficient and costly to operate. However, one of the reasons why it not possible to use a blockchain right away is because of the poor performance. Public blockchains, where anyone can participate, can only process a couple of transaction per second and is therefore far from usable in the world of finance. Permissioned blockchains is another type of blockchain where only a restricted set of users have the rights to decide what will be recorded in the blockchain. This allows permissioned blockchains to have a number of advantages over public blockchains. Most notably is the ability to split the network into segments where only a subset of nodes needs to validate transactions to aparticular application, allowing the use of parallel computing and better scaling. Moreover, the validating nodes can be trusted, allowing the use of consensus algorithm which offer much more through put. In this paper, we compare public blockchain with permissioned blockchain and address the notable trade-offs: decentralization, scalability and security, in the different blockchain networks. Furthermore, we examine the potential of using a permissioned blockchain to replace the old systems used in financial institutes and banks by launching a Hyperledger Fabric network and run stress tests. It is apparent that with less decentralization, the performance and scalability of Hyperledger Fabric network is improved and it is feasible that permissioned blockchain can be used in finance.
Ilya Sergey, Aquinas Hobor
In this paper, we explore remarkable similarities between multi-transactional behaviors of smart contracts in cryptocurrencies such as Ethereum and classical problems of shared-memory concurrency. We examine two real-world examples from the Ethereum blockchain and analyzing how they are vulnerable to bugs that are closely reminiscent to those that often occur in traditional concurrent programs. We then elaborate on the relation between observable contract behaviors and well-studied concurrency topics, such as atomicity, interference, synchronization, and resource ownership. The described contracts-as-concurrent-objects analogy provides deeper understanding of potential threats for smart contracts, indicate better engineering practices, and enable applications of existing state-of-the-art formal verification techniques.
Daniele Magazzeni, Peter McBurney, William L. Nash
Smart contracts might encode legal contracts written in natural language to represent the contracting parties' shared understandings and intentions. The issues and research challenges involved in the validation and verification of smart contracts, particularly those running over blockchains and distributed ledgers, are explored.
Eliza Mik
No abstract is available for this record.
Massimo Bartoletti, Livio Pompianu
Smart contracts are computer programs that can be consistently executed by a network of mutually distrusting nodes, without the arbitration of a trusted authority. Because of their resilience to tampering, smart contracts are appealing in many scenarios, especially in those which require transfers of money to respect certain agreed rules (like in financial services and in games). Over the last few years many platforms for smart contracts have been proposed, and some of them have been actually implemented and used. We study how the notion of smart contract is interpreted in some of these platforms. Focussing on the two most widespread ones, Bitcoin and Ethereum, we quantify the usage of smart contracts in relation to their application domain. We also analyse the most common programming patterns in Ethereum, where the source code of smart contracts is available.
Patrick McCorry, Siamak F. Shahandashti, Feng Hao
No abstract is available for this record.
Zac Zimmer
Bitcoin, the digital cryptocurrency, has been celebrated as the future of money on the Internet. Although Bitcoin does present several forward-looking innovations, it also integrates a very old concept into its digital architecture: the mining of precious metals. Even though Bitcoin explicitly invokes mining as a metaphor and gold as an example for understanding the cryptocurrency, there has been little critical work on the connections between Bitcoin and previous metalist currency regimes. The following essay proposes a historical comparison with colonial South American silver mining and the global currency regime based on the New World silver peso it created as a way to interrogate Bitcoin. The comparison with colonial South America, and specifically the silver mining economy around the Cerro Rico de Potosí, will help to develop a historical and political understanding of Bitcoin's stakes, including questions of resources, labor, energy, and ecology. Mining and the extractive apparatus that accompanies it always imply massive-scale earthworks that reshape the planet itself, a process known as terraforming. The Potosí comparison will reveal Bitcoin to form part of a similar process of digital primitive accumulation we can provisionally name cryptoforming.
ESORICS 2017 Oslo, Joaquín García-Alfaro, Guillermo Navarro‐Arribas, Hannes Hartenstein · 7 authors
The DPM 2019 and CBT 2019 proceedings present the two ESORICS workshops on data privacy management and cryptocurrencies and blockchain technology. The papers are organized in parts on smart contracts and applications; and payment systems, privacy and mining; privacy preserving data analysis; etc.
Philipp Hacker, Chris Thomale
Cryptocurrencies, such as bitcoin and ethereum, have not only risen to public attention as novel means of payments, but also as facilitators of initial coin offerings (ICOs, also called token sales). In these entirely online-mediated offerings, entrepreneurs sell tokens registered on a blockchain in exchange for cryptocoins. Buyers receive tokens that can be understood as cryptographically-secured coupons which embody a bundle of rights and obligations. In July 2017, the SEC released an investigative report that highlighted that such tokens can be subject to the full scope of US securities regulation. It is unclear, however, to what extent EU securities regulation is applicable to ICOs and, particularly, whether issuers have to publish and register a prospectus in order to avoid criminal and civil prospectus liability in the EU. In conceptual terms, this depends on whether tokens are considered “securities” under the EU prospectus regulation regime. Against this background, this paper develops a nuanced approach that distinguishes between three archetypes of tokens: currency, investment, and utility tokens. It analyzes the differential implications of each of these types, and their hybrid forms, for EU securities regulation, and develops policy proposals for their regulation.
Leopoldo Catania, Stefano Grassi
From the Washington University Senior Honors Thesis Abstracts (WUSHTA), 2017. Published by the Office of Undergraduate Research. Joy Zalis Kiefer, Director of Undergraduate Research and Associate Dean in the College of Arts & Sciences; Lindsey Paunovich, Editor; Helen Human, Programs Manager and Assistant Dean in the College of Arts and Sciences Mentors: Mina Lee and Li Yang