Blockchain Papers

Kartik Hegadekatti

No abstract is available for this record.

Ralph C. Maloumby-Baka, Christian Kingombe

The paper reviews the last technological tools that arguably can contribute to reducing the excessively high costs of remittance transactions in Africa. Indeed, despite huge remittance inflows to and within the continent, Africa is the most expensive destination to send money to. As remittances have become more important than Overseas Development Assistance and Foreign Direct Investment inflows in some countries, it has become crucial to explore technological advances that can contribute to reducing their transaction costs. Such reduction would enable the end beneficiaries to capture a larger share of these external resources, which in turn could have an even bigger impact on development in Africa. In addition to revisiting the role of mobile banking in lowering remittance transaction prices, the paper takes a closer look at the newest available technology, the Bitcoin blockchain technology that underpins digital currencies. At this early stage, very few social science researchers have addressed the role that such digital currency could play in the reduction of the remittance transaction prices, except for a few innovative Bitcoin operators. The paper proceeds as follows. It first looks at the causes of the high remittance transaction costs. Then, it reviews, presents and analyses the official remittances data downloaded from the World Bank's Remittances Prices Worldwide database. It also briefly reviews a few remittance transfer technological instruments. Given the novelty of the topic, the review of the most recent existing "literature" on Bitcoin is mainly retrieved from either on - line news sources or information from a few leading Bitcoin operators. In the light of the UN Global Working Group Post-2015 Development Agenda and Sustainable Development Goals proposal to reduce by 2030 the remittance transaction costs to even less than 3%, the effectiveness of these new technological instruments to reach such objective are discussed. Finally, a number of appropriate policy actions to foster the economic impact of remittances are proposed.

Scott Shackelford, Steven Myers

Published as: Shackelford, S., and S. Myers. 2017. “Block-by-Block: Leveraging the Power of Blockchain Technology to Build Trust and Promote Cyber Peace.” Yale Journal of Law & Technology 19:334–388. 
\n"There has been increasing interest in the transformative power of not only crypto-currencies like Bitcoin, but also the technology underlying them—namely blockchain. To the uninitiated, a blockchain is a sophisticated, distributed online ledger that has the potential, according to Goldman Sachs, to 'change everything.' From making businesses more efficient to recording property deeds to engendering the growth of ‘smart’ contracts, blockchain technology is now being investigated by a huge range of organizations and is attracting billions in venture funding. Even the U.S. Defense Advanced Research Projects Agency (DARPA) is investigating blockchain technology to 'create an unhackable messaging system.' However, the legal literature has largely ignored the rise of blockchain technology outside of its finance, securities, and copyright implications. This Article seeks to address this omission by analyzing the potential impact of blockchain technology on advancing the cybersecurity of firms across an array of sectors and industries with a particular focus on certificate authorities and the critical infrastructure context. Moreover, we examine the rise of blockchains through the lens of the literature on polycentric governance to ascertain what lessons this research holds to build trust in distributed systems and ultimately promote cyber peace."

Hans Peter Grüner, Christoph Siemroth

Abstract We show how decentralized individual investments can efficiently allocate capital to innovating firms via equity crowdfunding. We develop a model where consumers have privately known consumption preferences and may act as investors. Consumers identify worthwhile investments based on their own preferences and invest in firms whose product they like. In the presence of aggregate demand uncertainty, an efficient capital allocation is achieved if all groups of consumers have enough liquidity to invest. If some groups of consumers cannot invest, capital flows reflect preferences of liquid investors but not future demand. Comparing with traditional financing forms, crowdfunding in the absence of liquidity constraints can be superior unless traditional financiers are fully competitive and perfectly informed.

Mihails Ļevenčiks

Darba mērķis ir Ethereum decentralizētas programmatūras platformas pētīšana. Darbā tiek pētītas tehnoloģijas uz kurām balstās decentralizētās programmatūras platforma, programmatūras izstrādes process tajā un platformas stiprās un vājās puses. Darba praktiskajā daļā, tiek izveidots decentralizētas kopfinansēšanas sistēmas prototips Ethereum platformā.

Michel Rauchs

No abstract is available for this record.

Salete Oro Boff, Natasha Alves Ferreira

La tecnología trajo conceptos que, fundidos con el campo económico, permitieron soluciones a problemas que la sociedad enfrentó varias veces a lo largo de su historia, como: inflación, ciclos económicos, instituciones financieras no confiables y la falta de universalización de servicios financieros a toda población. Este artículo pretende elucidar tanto la parte conceptual de Bitcoin abordando los aspectos históricos, económicos y jurídicos, así como los posibles beneficios sociales que la moneda puede traer como una primera alternativa, basada en tecnología, al dinero tradicional controlado por el Estado. El método utilizado para ello es el deductivo y la técnica de investigación es la bibliográfica, partiendo de ejemplos de la utilización del dinero a lo largo de la historia y del ascenso de Bitcoin como moneda.

Andrew Miller

The past several years have seen the surprising and rapid rise of Bitcoin and other “cryptocurrencies.” These are decentralized peer-to-peer networks that allow users to transmit money, tocompose financial instruments, and to enforce contracts between mutually distrusting peers, andthat show great promise as a foundation for financial infrastructure that is more robust, efficientand equitable than ours today. However, it is difficult to reason about the security of cryptocurrencies. Bitcoin is a complex system, comprising many intricate and subtly-interacting protocol layers. At each layer it features design innovations that (prior to our work) have not undergone any rigorous analysis. Compounding the challenge, Bitcoin is but one of hundreds of competing cryptocurrencies in an ecosystem that is constantly evolving. The goal of this thesis is to formally reason about the security of cryptocurrencies, reining in their complexity, and providing well-defined and justified statements of their guarantees. We provide a formal specification and construction for each layer of an abstract cryptocurrency protocol, and prove that our constructions satisfy their specifications. The contributions of this thesis are centered around two new abstractions: “scratch-off puzzles,” and the “blockchain functionality” model. Scratch-off puzzles are a generalization of the Bitcoin “mining” algorithm, its most iconic and novel design feature. We show how to provide secure upgrades to a cryptocurrency by instantiating the protocol with alternative puzzle schemes. We construct secure puzzles that address important and well-known challenges facing Bitcoin today, including wasted energy and dangerous coalitions. The blockchain functionality is a general-purpose model of a cryptocurrency rooted in the “Universal Composability” cryptography theory. We use this model to express a wide range of applications, including transparent “smart contracts” (like those featured in Bitcoin and Ethereum), and also privacy-preserving applications like sealed-bid auctions. We also construct a new protocol compiler, called Hawk, which translates user-provided specifications into privacy-preserving protocols based on zero-knowledge proofs.

Dr Craig S Wright

Bitcoin scripts currently do not enable loops. Therefore, they are commonly considered to be not Turing Complete. This limits the types of algorithms the Bitcoin scripts can execute to linear or tree-like instructions. This white paper describes the invention of an Oracle module that: • Continuously monitors the state of Blockchain. • Makes decisions based on the current state. • Generates the next set of transactions to be written onto the Blockchain. The above processes is executed continuously by the Oracle in parallel to the Blockchain network. It therefore implements looping constructs that makes the combined Oracle and Blockchain system Turing Complete. As old blocks cannot be erased from the Blockchain, but new blocks can be added, the Oracle and the Blockchain will work as a non-erasable Turing Machine as described in Minsky et al. (1967). We will discuss the use of the Oracle in applications including: • Distributed data storage • Distributed computing • The control of drones. We will also describe how metadata storage and digital signature authorization on the Blockchain can be useful features for implementing these applications.

Michel Avital, Roman Beck, John Leslie King, Matti Rossi · 5 authors

The panel focuses on blockchain, the technology behind Bitcoin and Ethereum. The topic has drawn much attention recently in both business and academic circles. The blockchain is a distributed, immutable digital record system that is shared among many independent parties and can be updated only by their consensus. If unbiased and incorruptible blockchain-based information systems become prevalent repositories of our records, trusting other humans with<br/>constructing and maintaining key records to define the resources at our disposal could become unnecessary. In principle, blockchain could provide a decentralized information infrastructure that no one fully controls, thereby no one has absolute power and no one can distort past or current records. The full potential let alone implications of blockchain is still unknown. The panel explores blockchain challenges and opportunities from the IS research perspective.

Shravanthi, R Pooja, Bhagya Shree J

Bitcoin is a crypto currency with several advantages over approaches. Transactions are confirmed and stored by a peer-to-peer network in a blockchain. Therefore, all transactions are public and soon solutions where designed to increase privacy in Bitcoin. Many come with downsides, like requiring a trusted third-party or requiring modifications to Bitcoin. In this paper, we compare these approaches according to several criteria. Based on survey, coin Join emerges as the best approach for anonymizing Bitcoins today.

Robert Leonhard

No abstract is available for this record.

Christian Decker

No abstract is available for this record.

Lawrence J. Trautman, Alvin C. Harrell

No abstract is available for this record.

Varun Puri

In this paper, I analyze Bitcoin price formation and adoption rates at a global and national level. In determining Bitcoin prices, I consider contemporaneous and lagged values of traditional determinants of currencies, such as inflation and industrial production, and digital currency specific factors, primarily public interest. Using monthly time-series data across five years (2011 – 2016), I find that global public interest in Bitcoin, measured by Google searches for the keyword ‘Bitcoin,’ has a positive and significant impact on Bitcoin prices. I extend the analysis to a country level by employing a proxy for adoption rates, represented by the number of local Bitcoin client downloads, which is a useful predictor of prices. I examine pooled data across 12 countries to show that searches for ‘Bitcoin’ can be used to predict adoption rates and, consequently, prices. To the best of my knowledge, this is the first academic article to study Bitcoin usage at a national level. I find that contemporaneous values of traditionally used macroeconomic determinants of currency prices, except inflation, do not have a significant impact on Bitcoin prices.

Colin Boyd, Christopher Carr

Client puzzles have been proposed as a mechanism for proving legitimate intentions by providing proofs of work, which can be applied to discourage malicious usage of resources. A typical problem of puzzle constructions is the difference in expected solving time on different computing platforms. We call puzzles which can be solved independently of client computing resources fair client puzzles. We propose a construction for client puzzles requiring widely distributed computational effort for their solution. These puzzles can be solved using the mining process of Bitcoin, or similar cryptocurrencies. Adapting existing definitions, we show that our puzzle construction satisfies formal requirements of client puzzles under reasonable assumptions. We describe a way of transforming our client puzzles for use in denial of service scenarios and demonstrate a practical construction.

Aggelos Kiayias, Giorgos Panagiotakos

A fundamental open problem in the area of blockchain protocols is whether the Bitcoin protocol is the only solution for building a secure transaction ledger. A recently proposed and widely considered alternative is the \GHOST protocol which, notably, was proposed to be at the core of Ethereum as well as other recent proposals for improved Bitcoin-like systems. % The \GHOST variant is touted as offering superior performance compared to Bitcoin (potentially offering block production speed up by a factor of more than 40) without a security loss. Motivated by this, in this work, we study from a provable security point of view the \GHOST protocol.<br/><br/>We introduce a new formal framework for the analysis of blockchain protocols that relies on trees (rather than chains) and we showcase the power of the framework by providing a unified description of the \GHOST and Bitcoin protocols, the former of which we extract and formally describe. We then prove that \GHOST implements a ``robust transaction ledger'' (i.e., possesses liveness and persistence) and hence it is a provably secure alternative to Bitcoin; moreover, our bound for the liveness parameter is superior to that proven for the bitcoin backbone in line with the original expectation for \GHOST. Our proof follows a novel methodology for establishing that \GHOST is a robust transaction ledger compared to previous works, which may be of independent interest and can be applicable to other blockchain variants.

Sergi Delgado-Segura, Cristina Pérez‐Solà, Jordi Herrera‐Joancomartí, Guillermo Navarro‐Arribas

No abstract is available for this record.

José Parra-Moyano

No abstract is available for this record.

Avi Spielman

Thesis: S.M. in Real Estate Development, Massachusetts Institute of Technology, Program in Real Estate Development in conjunction with the Center for Real Estate, 2016.

Paolo Tasca

No abstract is available for this record.

Yong Yu, Yannan Li, Man Ho Au, Willy Susilo · 6 authors

No abstract is available for this record.

Jill Carlson

The development of cryptocurrency technology has made it possible to transfer value securely and instantaneously without a third party intermediary such as a bank or financial institution. This is an exploratory analysis of where and why this technology has gained traction. In particular, I focus on the hypothesis that the relative popularity of cryptocurrency in Argentina can be explained by the presence of long-term capital controls. To test this hypothesis, I conducted expert interviews with market players. The main conclusion is that cryptocurrency can and has been used to evade capital controls. However, it is unlikely that substantial volumes have been moved via this mechanism. Cryptocurrency’s popularity in Argentina is attributable to more than the country’s history of capital controls or high rates of inflation. Other factors, including tax rate, levels of corruption, and history of multiple exchange rates have also contributed to adoption of this technology in Argentina. I propose further case study research on cryptocurrency in additional countries in order to develop these theories.

Siddharth Misra, Vishal Kashyap, Poonacha K.B., Arjun Mukund · 5 authors

Tema ovog rada su kriptovalute. Budući da većina ljudi nije pravodobno upoznata s ovom temom, ovaj rad prikazuje i opisuje kriptovalute te način na koji se upotrjebljuju u svakodnevnom životu. Kriptovalute (eng. cryptocurrency) digitalne su valute dizajnirane kao sredstvo razmjene. Poznate su po tome što su državne agencije i banke isključene iz procesa razmjene. Kriptovalute omogućuju jednostavnu, jeftinu i brzu transakciju na području cijeloga svijeta. Trenutno najisplativije kriptovalute su Bitcoin i Ethereum, a u radu je opisana njihova korisnost, prednosti i mane. Budući da se Bitcoinu predviđa uspješna budućnost i sve je prisutniji i prihvatljiviji na tržištu, u radu su navedeni primjeri iz Hrvatske koji to potvrđuju. Sve veći broj poduzetnika odlučuje se za uvođenje kriptovaluta. U primjerima je obuhvaćen širok spektar djelatnosti, od frizerskih usluga, preko raznih tvrtki koji se bave prodajom računalne opreme, ugostiteljskih usluga preko mogućnosti brzog i lakog podizana gotovine na kripto bankomatima pa sve do plaćanja komunalnih usluga, pa čak i humanitarno djelovanje. Mnogi smatraju da su kriptovalute samo sinonim za prijevare i pranje novca, no programeri tvrde da su kriptovalute samo jedna vrsta tehnologije, alat koji sam po sebi ne može biti ni dobar ni loš, ovisno o tome za što se koristi. Autor ovoga rada proveo je istraživanje o tome kako se može besplatno započeti trgovanje kriptovalutama te je anketom ispitao stavove ispitanika o implementaciji kriptovaluta u društvu.