Follow blockchain research across journals, conferences, and preprint repositories.
52,397 results · page 1865 of 2,184
Stefano Bistarelli, Claudio Pannacci, Francesco Santini
No abstract is available for this record.
Katharina Zeuch, Kai Hendrik Wöhnert, Volker Skwarek
Due to increasing security requirements e. g. for transaction based smart-x-technologies in distributed systems, blockchain technologies are predestined for secure data exchange and keeping in distributed systems. Although the underlying principle of almost every blockchain is the Byzantine fault tolerance (BFT), its implementation differs significantly between the technologies so that migration or interoperability between systems is nearly impossible. Additionally, this missing interoperability also reduces the chance for scalability between different extents of implementation as there is usually not a one-size-fits-all-blockchain: Different technologies have their advantages for different systems. Therefore scalability and interoperability are tightly coupled. As a basis for further research on and the derivation of generally scalable and interoperable architectures of blockchains, current technologies have to be made comparable and interoperability criteria have to be developed. This paper analyses current literature and introduces technical criteria for the comparison of blockchainand distributed ledger technologies (BC/DLT).With a list of eleven criteria popular BC/DLTs such as Bitcoin, Ethereum, Hyperledger Fabric, Ripple and Corda are compared regarding general features.
Simon Farshid, Andreas Reitz, Peter Roßbach
Practitioners as well as academics expect that blockchain technology is a game changer for a variety of use cases. This is because of its feature of transaction immutability enabled by keeping a history of all transactions. Nevertheless, this strength can become its biggest weakness. There already exists a lively discussion on scenarios where it is necessary to delete submitted data from the chain after it is no longer needed. This becomes even more crucial with the introduction of the European General Data Protection Regulation (GDPR). In this paper we make use of a design science research (DSR) approach to design an IT artifact in form of a prototype that maintains most of the key features of blockchain technology but deletes old data. We evaluate the prototype with help of experts to investigate what to expect from blockchains that delete data and derive principles on how to design them.
Ingrid Bauer, Liudmila Zavolokina, Fabian Leisibach, Gerhard Schwabe
Blockchain is expected to create a variety of new opportunities for businesses. Yet, little is known about how companies can exploit business value from the technology. However, without a clear understanding of how, and corresponding adaption of business practices, the realization of value is doomed to failure. Hence, we contribute to this gap by analyzing and explicating the specificities of value creation from blockchain in the ecosystem of a car. In the course of an exploratory case analysis we conducted interviews and workshops with industry and blockchain experts from five diverse stakeholder groups. In brief, we provide early evidence that (1) blockchain enables value creation through: Distributed Product Innovation, Controlled Customer Intimacy and Shared Operational Efficiency. Further, (2) we derive guidelines and discuss learnings for other businesses aiming to leverage value from blockchain technology.
Martin Fleischmann, Björn Sven Ivens
While interest in blockchain technology and applications increases, research studying the role of trust as an element that leads potential users and consumers to adopt and accept the technology remains scarce. This study conducts acceptance research that expands beyond traditional acceptance models and explores the role of trust from the user/consumer perspective. It provides comprehensive insights from the user/consumer angle and a deeper understanding of the role of trust in blockchain adoption. Using an inductive research approach that builds theory from qualitative empirical data, this paper identifies trust as a critical benefit of blockchain technology and applications, encompassing both functional (economic and system-/ process-related) as well as emotional benefits (social and personal). As trust spans across functional and emotional benefit dimensions, this study suggests that trust is a key driver for user/consumer adoption of blockchain technology and applications.
Adrien Ghosn, James R. Larus, Edouard Bugnion
Trusted Execution Environments (TEEs), such as Intel SGX enclaves, use hardware to ensure the confidentiality and integrity of operations on sensitive data. While the technology is available on many processors, the complexity of its programming model and its performance overhead have limited adoption. TEEs provide a new and valuable hardware functionality that has no obvious analogue in programming languages, which means that developers must manually partition their application into trusted and untrusted components. This paper describes an approach that fully integrates trusted execution into a language. We extend the Go language to allow a programmer to execute a goroutine within an enclave, to use low-overhead channels to communicate between the trusted and untrusted environments, and to rely on a compiler to automatically extract the secure code and data. Our prototype compiler and runtime, GOTEE, is a backward-compatible fork of the Go compiler. The evaluation shows that our compiler-driven code and data partitioning efficiently executes both microbenchmarks and applications. On the former, GOTEE achieves a 5.2×throughput and a 2.3× latency improvement over the Intel SGX SDK. Our case studies, a Go ssh server, the Go tls package, and a secured keystore inspired by the go-ethereum project, demonstrate that minor source-code modifications suffice to provide confidentiality and integrity guarantees with only moderate performance overheads.
José Domingo Portero Lameiro, Elisabeth T. Pereira
espanolLas economias modernas son hoy en dia economias monetarias, en las que el dinero desempena un papel fundamental en el desarrollo, la estabilidad y el bienestar de las naciones y sus poblaciones. Keynes (1936) subrayo que las economias del siglo XX ya no eran economias de cambio, sino economias monetarias en las que el dinero desempena un papel predominante. La relevancia del dinero en las economias modernas ha evolucionado con la evolucion de la sociedad y con la tecnologia, el conocimiento y las nuevas formas de comunicacion que caracterizan a los siglos XX y XXI, especialmente a este ultimo. Con este fin, el proposito de este capitulo es describir la importancia y la evolucion del dinero en las economias modernas en los ultimos cien anos, sobre la base de una estructura general y evolutiva que caracteriza al sistema financiero y monetario mundial de tendencias actuales y futuras, en su integracion de tecnologias, nuevos instrumentos financieros y nuevas formas de pago. Este articulo pretende describir teoricamente, y utilizando estudios de casos reales siempre que sea posible, la importancia y la evolucion del dinero en las economias modernas, considerando la evolucion del dinero sufrida desde la revolucion industrial, a traves de las diversas formas de dinero y las demandas de dinero. los sistemas financieros y monetarios en los ultimos cien anos, hasta el dia de hoy y las tendencias futuras de los sistemas y formas de pago. Se considerara el dinero metalico, el papel moneda, el dinero escritural, el dinero plastico y, sobre todo, la existencia de dinero electronico basado en transferencias electronicas y sistemas de pago electronico y las criptodivisas (por ejemplo, Bitcoin) que surgieron a finales de la primera decada del siglo XXI. Se presentaran los distintos conceptos que intervienen en la descripcion del dinero y que permiten un mayor conocimiento sobre este tema. Al final se presentaran las tendencias futuras. EnglishThe modern economies of nowadays are monetary economies, where money has a key role in the development, stability and welfare of nations and their populations. Keynes (1936) emphasized that the Economies of 20th century were not more change economies but monetary economies in which money have a preponderant role. The relevance of money in modern economies has evolved with the evolution of society and with the technology, knowledge and new forms of communication that characterize the 20th and 21st centuries, especially with the latter one. With this purpose, the aim of this chapter is describe the importance and evolution of money in modern economies in the last hundred years, based in the a general and evolutionary framework that characterizes the global financial and monetary system of today and future trends, on its integration on technologies, new financial instruments and new forms of payments. This article aims to describe theoretically, and with recourse to real cases of study whenever possible, the importance and evolution of money in modern economies, considering the evolution of the currency suffered since the industrial revolution, through the various forms of money and requirements of the financial and monetary system in the last hundred years, until today and future trends of the systems and form of payments. Will be considered the metallic money, paper money, scriptural money, plastic money and above all the existence of electronic money based on electronic transfers and systems of electronic payments and the crypto-coins (for example the Bitcoin) that emerged at the end of the first decade of the 21st century. The various concepts involved in the currency description and that allow a greater knowledge on this topic will be presented. Future trends will be presented at the end.
Chunlin Lang, Yang Hu, Les Oxley, Yang Hou
No abstract is available for this record.
Jamal Bouoiyour, Refk Selmi, Olivier Hueber
Over the past few years, cryptocurrencies (especially Bitcoin) have attracted a particular attention. As the number of transactions increase, these systems tend to become slower, expensive, and unsustainable for a use-case such as payment. In this way, the Bitcoin sidechain seeks to provide prompt and confidential transactions between major trading platforms. Although poor performance and high volatility can push potential users away from Bitcoin, this study reveals that the introduction of sidechain solves some of the problems Bitcoin is facing. Using relatively new techniques, we find that the implementation of sidechain reduces Bitcoin price volatility, rises its efficiency, and enhances its usefulness as a transaction tool and a diversifier. We explain these changes in Bitcoin characteristics by the sidechain"s capacity to speed up the circulation of money by shortening block validation times and to an improvement in the scalability of Proof of Work and Bitcoin payment services. Our results also indicate that the sidechain liquid network lead to a less energy-consuming and in turn to less polluting Bitcoin system. But a weakly vanishing causality between Bitcoin mining and Bitcoin energy consumption implies that the concentration of miners is still follow available electrical supply.
Letícia Oliveira de Melo
El presente estudio tiene por objeto demostrar la relevancia, pertinencia, urgencia y necesidad de la Distributed Ledger Technology, específicamente el Blockchain, como medio de prueba en el derecho procesal civil. Siendo una garantía constitucional el derecho a la producción de prueba, demostraremos la inevitabilidad de admisión de ese tipo de prueba en el Derecho. En consecuencia, debido a la ausencia de previsión legislativa expresa sobre la admisibilidad de dicha tecnología en el derecho probatorio, tomaremos como base los estudios de Barbosa Moreira sobre pruebas atípicas para constatar una posible adecuación de esa prueba a esta clasificación.
Daniel Köhler, Anna Galika, Qiuru Pu, Junyi Bai
The paper aims for new urban forms of property enabled by computation models of distributed ledgers as they are currently being deployed with technologies like Blockchain. Distributed ledgers promise to constitute whole environments by chaining and sharing blocks of data. Upscaling this prospective, the paper describes objects with unique and strong compositional characteristics that act as closed black boxes and are able through distribution to create large scale effects. The final result of the nesting is the Interchain, a chain of chains that initiate with the characteristics of the contributing chains, and due to the distribution, unprecedented patterns arise. The resulting Interchain, observed with spatial and architectural characteristics, can project a new building form and a new urban model based on blockchain theory.
Bronwyn Howell, Petrus H. Potgieter, Bert M. Sadowski
No abstract is available for this record.
Axel Beelen
No abstract is available for this record.
Tong Sui Jun, Yong Yang, Wen Sun, Eryu Xia · 5 authors
Collection and management of clinical data for administration and analysis is a time-consuming and complex task, especially when multiple data providers been involved. Even if people are willing to take on the burden for it, there is still no mature solution to protect data privacy for distributed data providers. Distributed ledger is an emerging technology that supports decentralized data sharing and management. Based on this, we present a platform which enables distributed and truthful data collection and serves privacy-preserving needs in clinical data management. Our system, built on Hyperledger Fabric, used smart contract to execute data aggregation and provide basic analysis methods. The system used ledger and world status to record data access history and other metadata. This decentralized platform enables data providers to proactively share and protect their data, Thus can simplify clinical data collection procedure and promote efficient collaboration between providers.
Eli M. Noam
No abstract is available for this record.
Shaomin Zhang, Pu Miao, Baoyi Wang, Bin Dong
Low cost, high efficiency, price transparency, and timely settlement of transactions are required for direct transactions between electricity providers and consumers in the microgrids. So the blockchain technology and the continuous double auction mechanism for direct electricity trading have always been a hot topic in the field of microgrids.In order to further reduce the transaction cost of blockchain and increase the transaction efficiency, and to solve the problem of lack of privacy protection for continuous double auction in the existing scheme, a privacy protection scheme of microgrids direct electricity transaction based on consortium blockchain and the continuous double auction is proposed. In it, the combination of consortium blockchain technology and continuous double auction mechanism is applied to reduce costs and improve the efficiency of transactions. In the meanwhile, pseudonyms and pseudonym certificates are generated by fair blind signature technology to realize identity privacy in the continuous double auction. And decentralization and user identity traceability are achieved by using (t, n) threshold secret sharing technology which distributes and recovers the private key of a trusted third party. The theoretical security analysis shows that the privacy protection scheme has higher security. The simulation experiment shows that the consortium blockchain technology has lower cost and higher efficiency in this scheme.
Christiana Aristidou, Evdokia Marcou, Evdokia Marcou, 80, Griva Digeni, Swepco Court 6, 2nd Floor, 3101 Limassol, Cyprus
Many people talk about blockchain but very few understand its true nature and potential. Blockchain seems very exciting yet simultaneously a bit confusing, and naturally many people, businesses, and governments approach it with high expectations while also exhibiting some hesitancy. This article will deal with the use of blockchain in relation to government applications. A proper assessment of such use requires a discussion on blockchain standards, which are currently developed, or may develop in the future. Without blockchain standards, any potential use of blockchain in government will be of limited and restricted value. This would render our discussion on government applications rather limited too. Standards enable us to appreciate blockchain applications in a useful way for future applications outside the context of government. Focusing our attention to government applications is deliberate. Blockchain, obviously, provides amazing opportunities for the private sector. Over the last years there has been widespread public disbelief in many public and government institutions. Corruption, fraud, lack of transparency, alienation and disconnection of citizen from decision-making centres oblige governments to change and offer proper governance conditions for their citizens. Further, higher consumer expectations in all sectors of the economy naturally affect the expectations of citizens vis--vis their governments. For the above reasons, governments could leverage the positive features of blockchain to restore their
John Taskinsoy
No abstract is available for this record.
Pedro Bustamante, Marcela Gomez, Martin B. H. Weiss, Taieb Znati · 6 authors
No abstract is available for this record.
Olga Sushko, А.А. Kaznin
No abstract is available for this record.
Eder J. Scheid, Manuel Keller, Muriel Figueredo Franco, Burkhard Stiller
Current projects applying blockchain technology to enhance the trust of NFV environments do not consider the VNF repository. However, the blockchain’s properties can enhance trust by allowing to verify a VNF package’s integrity without relying (a) on a Trusted Third Party (TTP) for remote attestation or (b) a secure database. This paper presents BUNKER , a Blockchain-based trUsted VNF packagE Repository, intended to be integrated with traditional database-based package verification environments, acting as a trusted repository containing VNF package information. Moreover, BUNKER allows users to acquire VNFs without the need of a TTP using an Ethereum Smart Contract (SC). The SC automatically transfers license fees to the vendor once a VNF is acquired, and sends the VNF package’s link to the buyer before verifying its integrity.
Qiong Wu
This dissertation presents the application of microstructure theory on the RMB exchange rate\nand Bitcoin market price. The existing research on the RMB exchange rate and Bitcoin market price\nmainly studied their statistical characteristics through empirical methodologies. This dissertation\nfills the research gap in microstructure theory applied to the RMB exchange rate and Bitcoin market\nprice. First, the model for the determination of the two Renminbi (RMB) exchange rates and their\ninteractions is established, and empirical analysis suggests that the interactions among the two\nexchange rates and the explanatory variables are time-varying, in particular, after the "811 RMB\nexchange rate reform", the offshore RMB exchange rate replaced the onshore RMB exchange rate as\nthe leading indicator. Second, a model describing the speculative behavior in the Bitcoin trading\nmarket is developed. This theoretical model captures the statistical characteristics of Bitcoin\nmarket prices. The fundamental value of Bitcoin system is controversial, and the mysterious and\ninnovative features of the Bitcoin system incite the speculation behaviours. The speculation leads\nto the market bubble that brought the soaring and plunges of Bitcoin market price. Finally, an\neconomic model for Bitcoin mining competition based on the Bitcoin protocol is established, which\nprovides a benchmark for further research on mining competition in economics. For any Bitcoin\nminers, the equilibrium input depends on the comparison of the miner's own marginal cost with\nthat of other miners, however, whether profit can be obtained or not depends on the miner's own\nfixed cost.
Luis Cintron, Scott Graham, Douglas D. Hodson, Barry Mullins
No abstract is available for this record.
Peter GL Hunn, Accord Project, UK
Smart contracts on a blockchain network can be implemented to control digital value. A key question that arises is the extent to which smart contracts can, or should, operate as "smart legal contracts". Simply put, can smart contracts meet requirements of validity at law and practical efficacy. In order to achieve the goal of value maximization, the efforts of policy-makers, standards organisations and regulators should be informed by first principles. Standards, and other regulatory activities, must be driven by consideration of the technolegal functions of contracting. Blockchain-based smart contracts offer the potential to reduce transaction costs through new methods of stateful computation. When applied to commercial transactions, smart contracts can represent enforcement of an executed state. This paper argues that distributed ledger and smart contracts standards should seek to provide sufficient flexibility to facilitate contracting parties to coordinate in an optimal manner.