Follow blockchain research across journals, conferences, and preprint repositories.
50,752 results · page 1987 of 2,115
Dimaz Ankaa Wijaya, Joseph K. Liu, Dony Ariadi Suwarsono, Peng Zhang
No abstract is available for this record.
Iris H‐Y Chiu
This article analyses the existing institutions and infrastructure for payments. Authoritative settlement based on central bank support is seen as being essential for both large value and retail payment systems; and, in the EU, UK, and US, the importance of regulating for the protection of consumers who use retail payment systems is recognised. In this institutional context, payment innovations (including Bitcoin and distributed ledger or autonomous organisation technologies) are assessed. It is suggested that, while competition at certain levels is likely to bring social benefits through commercial developments, the maintenance of public interest objectives necessarily delineates the scope of competition. While this might limit the disruptive impact of payment innovations, it is argued that, in the light of the public policy needs for a stable and efficient public infrastructure and the social needs of confidence and trust in a predictable and regulated payment system that meets commercial and social expectations such as in consumer protection, this is not necessarily undesirable.
Maria Karajovic, Henry Kim, Marek Laskowski
Abstract This paper aims to propound a thorough and circumspect analysis of the implications of blockchain technology in the accounting profession and its broader industry. The analysis begins with a summary of early developments by first movers and how they are harnessing blockchain technology to improve business practices. Concomitantly, the paper will go on to discuss how this technology will streamline accounting processes, specifically as the technology approaches critical mass. Finally, a discussion of its long‐term implications will follow through a more philosophical and conceptual dialogue. Throughout the paper, criticisms will be raised to address concerns regarding blockchain's widespread use.
Malachy Mathews, Dan Robles, Brian Bowe
This paper provides an overview of historic and current organizational limitations emerging in the Architecture, Engineering, Construction, Building Owner / Operations (AECOO) Industry. It then provides an overview of new technologies that attempt to mitigate these limitations. However, these technologies, taken together, appear to be converging and creating entirely new organizational structures in the AEC industries. This may be characterized by the emergence of what is called the Network Effect and it’s related calculus. This paper culminates with an introduction to Blockchain Technology (BT) and it’s integration with the emergence of groundbreaking technologies such as Internet of Things (IoT), Artificial Intelligence (AI), Machine Learning (ML) and Financial / Insurance products. To illustrate this process, we use choose Building Information Modelling (BIM) technology as our model network database for the AECOO industry. Interaction with the BIM database is an activity that generates economic value which may be measured into existence by an electronic token that rewards disassociated parties for maintaining and improving the database for the benefit of all, thereby replacing the 3rd party intermediary characteristic of legacy hierarchies with a simple and efficient “digital handshake”. Not unlike feudalism before it, hierarchical structures are being disrupted by emerging network platforms. In the age of the Internet, social network structure are now more efficient and massively scalable. As with all social revolutions, people naturally reorganize to the system that provides better security, greater fault tolerance, ease of regulation, and greater market efficiencies. There is evidence all around that we are witnessing a digital transformation in the AECOO industry. The technologies of this transformation are disruptive to the existing professions, project procurement and building operation processes. The underlying calculus that threatens the AECOO industry is related to the process of legacy organizational structure. Hierarchical structures are being replaced by network structures in many industries simply because networks are more efficient, enjoy higher market valuation, they are fault tolerant, and self regulating whereas hierarchy requires substantial managerial and administration overhead to secure individual nodes. This can be a good thing because the incentive to disrupt older processes will often spring forth new systems and methods that have the potential to be leaner, more efficient, less error prone, and more cost effective across the enterprise. However, there is one essential element that is still problematic. Everyone trusts the old system with its inherent faults and may even be deeply vested in mitigating those faults. The same or greater level of trust must be demonstrated and maintained in any new system in order to be adopted and lead to commercial success.
Robert Leonhard
No abstract is available for this record.
Madars Virza
Thesis: Ph. D., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2017.
Federico Panisi
No abstract is available for this record.
Jin Enyi, Ngoc Tien Thanh Le
No abstract is available for this record.
Philipp Hacker
No abstract is available for this record.
Christoph Kinkeldey, Jean‐Daniel Fekete, Petra Isenberg
BitConduite is a system we are developing for the visual exploration of financial activity on the Bitcoin network. Bitcoin is the largest digital pseudo-currency worldwide and its study is of increasing interest and importance to economists, bankers, policymakers, and law enforcement authorities. All financial transactions in Bitcoin are available in an openly accessible online ledger-the (Bitcoin) blockchain. Yet, the open data does not lend itself easily to an analysis of how different individuals and institutions-or entities on the network-actually use Bitcoin. Our system BitConduite offers a data transformation back end that gives us an entity-based access to the blockchain data and a visualization front end that supports a novel high-level view on transactions over time. In particular, it facilitates the exploration of activity through filtering and clustering interactions. We are developing our system with experts in economics and will conduct a formal user study to assess our approach of Bitcoin activity analysis.
Charlie Shier, Muhammad Mehar, Alana Giambattista, Elgar Gong · 8 authors
No abstract is available for this record.
Christian Cachin, Marko Vukolić
A blockchain is a distributed ledger for recording transactions, maintained by many nodes without central authority through a distributed cryptographic protocol. All nodes validate the information to be appended to the blockchain, and a consensus protocol ensures that the nodes agree on a unique order in which entries are appended. Consensus protocols for tolerating Byzantine faults have received renewed attention because they also address blockchain systems. This work discusses the process of assessing and gaining confidence in the resilience of a consensus protocols exposed to faults and adversarial nodes. We advocate to follow the established practice in cryptography and computer security, relying on public reviews, detailed models, and formal proofs; the designers of several practical systems appear to be unaware of this. Moreover, we review the consensus protocols in some prominent permissioned blockchain platforms with respect to their fault models and resilience against attacks.
Ben Fisch, Rafael Pass, Abhi Shelat
Mining for Bitcoins is a high-risk high-reward activity. Miners, seeking to reduce their variance and earn steadier rewards, collaborate in pooling strategies where they jointly mine for Bitcoins. Whenever some pool participant is successful, the earned rewards are appropriately split among all pool participants. Currently a dozen of different pooling strategies (i.e., methods for distributing the rewards) are in use for Bitcoin mining. We here propose a formal model of utility and social welfare for Bitcoin mining (and analogous mining systems) based on the theory of discounted expected utility, and next study pooling strategies that maximize the social welfare of miners. Our main result shows that one of the pooling strategies actually employed in practice--the so-called geometric pay pool--achieves the optimal steady-state utility for miners when its parameters are set appropriately. Our results apply not only to Bitcoin mining pools, but any other form of pooled mining or crowdsourcing computations where the participants engage in repeated random trials towards a common goal, and where "partial" solutions can be efficiently verified.
Carla Reyes
No abstract is available for this record.
Peter Mell, John Kelsey, James M. Shook
Most modern electronic devices can produce a random number. However, it is difficult to see how a group of mutually distrusting entities can have confidence in any such hardware-produced stream of random numbers, since the producer could control the output to their gain. In this work, we use public and immutable cryptocurrency smart contracts, along with a set of potentially malicious randomness providers, to produce a trustworthy stream of timestamped public random numbers. Our contract eliminates the ability of a producer to predict or control the generated random numbers, including the stored history of random numbers. We consider and mitigate the threat of collusion between the randomness providers and miners in a second, more complex contract.
Marco Bianchetti, Camilla Ricci, Marco Scaringi
The growth of peer-to-peer exchanges and the blockchain technology has led to a proliferation of cryptocurrencies and to a massive increase in the number of investors who actually negotiate digital money. Cryptocurrencies trade at prices mainly driven by investor sentiment, becoming a potential source of financial bubbles and instabilities. In this work, we apply quantitative models to the study of Bitcoin and Ether, two of the most famous cryptocurrencies. Our bubble detection methodology combines the Log Periodic Power Law (LPPL) model, originally created by Johansen, Ledoit and Sornette (JLS), and the statistical model developed by Phillips, Shi, and Yu (PSY). In particular, we employ three different versions of JLS model, i.e. Ordinary Least Square (OLS), Generalised Least Squares (GLS) and Maximum Likelihood Estimation (MLE), and two PSY statistical tests (BSADF and BSADF*). We find that, during the sample period 1st December 2016 - 16th January 2018, Bitcoin shows typical hallmarks of a bubble phase in mid December 2017 and in the first half of January 2018, anticipating the large crashes observed thereafter. Also the Ether price dynamics reveals bubble evidence in mid June 2017, anticipating the crash observed on 12th June, and a weaker signal around 12th January 2018, anticipating the crash observed in the same days. This paper confirms the high risk of speculative bubbles associated with cryptocurrencies, related to investor exuberance pumping market prices far away from their fundamental values, thus creating critical situations subject to possible crashes. Our methodology is general and can be applied to virtually any financial time series, and may support investing and risk management strategies.
Nancy Nakamoto
No abstract is available for this record.
Jonathan Chiu, Thorsten V. Koeppl, Chiu, Jonathan, Koeppl, Thorsten
How well can a cryptocurrency serve as a means of payment? We study the optimal design of cryptocurrencies and assess quantitatively how well such currencies can support bilateral trade. The challenge for cryptocurrencies is to overcome double-spending by relying on competition to update the blockchain (costly mining) and by delaying settlement. We estimate that the current Bitcoin scheme generates a large welfare loss of 1.4% of consumption. This welfare loss can be lowered substantially to 0.08% by adopting an optimal design that reduces mining and relies exclusively on money growth rather than transaction fees to finance mining rewards. We also point out that cryptocurrencies can potentially challenge retail payment systems provided scaling limitations can be addressed.
Dietmar Peetz, Gregory Mall
No abstract is available for this record.
Siamak Solat, Maria Potop-Butucaru
No abstract is available for this record.
Emmanuelle Anceaume, Romaric Ludinard, Maria Potop-Butucaru, Frédéric Tronel
No abstract is available for this record.
Louise Axon, Michael Goldsmith
Conventional public-key infrastructure (PKI) designs using certificate authorities and web-of-trust are not optimal and have security flaws. The properties afforded by the Bitcoin blockchain are a natural solution to some of the problems with PKI - in particular, certificate transparency and elimination of single points-offailure. Proposed blockchain-based PKI designs are built as public ledgers linking identity with public key, providing no privacy. We consider cases requiring privacy-aware PKIs, which do not link identity with public key. We show that blockchain technology can be used to construct a privacy-aware PKI while eliminating some of the problems of conventional PKI, and present PB-PKI, a privacy-aware blockchain-based PKI.
Svein Ølnes, Arild Jansen
No abstract is available for this record.
L Er-Rajy, El Kiram My A, El Ghazouani M, Omar Achbarou
Bitcoin has experienced rapid growth in the transactions number and in their value since its appearance in 2008. Its success is mainly due to the innovative use of a peer-to-peer network to implement all aspects of the currency life cycle, from creation to transfer between users. Bitcoin offers cash transactions that are almost instant and non-refundable, while allowing truly global transactions processed at the same speed as local ones. It offers a public transactions history, which allows untrusted audibility, and introduces many new and innovative use cases such as smart property, micropayments, contracts and escrow transactions for disputes mediation. However, the same features that make Bitcoin attractive to its end users are also its main limitations. Its decentralized nature limits the number of transactions and the speed at which transactions can be carried out and confirmed. The problem with slow confirmations is combined with the semantics of the confirmations which are not definitive, requiring several confirmations and further delaying the transaction acceptance. In this paper, we described the operating principles of peer-to-peer cryptographic currencies and especially security of bitcoin system. Moreover, For Bitcoin enhancements and additional mitigations we provide ideas for node auditing users in the network in aim to keep clients from the trusted transaction branch database generated by the attackers.