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Panagiota K. Makrichoriti, George Moratis
No abstract is available for this record.
Алексей Чурилов
Cryptocurrencies have become very popular in past few years. At recent time Bitcoin holds a dominant position on cryptocurrency markets. Lots of economists, programmers, bloggers, even lawyers call Bitcoin ?money of the future? or ?a pure means of payment?. But is Bitcoin and cryptocurrencies the money in the classic meaning of this phenomenon? Economic theory identifies money through the role that it plays in society, but can Bitcoin fulfill these functions? This paper discusses the nature of Bitcoin from the economic and legal perspective.Despite all controversies Bitcoin is used in business. Bitcoins and their use are a very actual issue, especially with a high popularity and high cost of Bitcoins. The paper covers the issue of legal status of Bitcoin and how can it be used in business activity, including examination of both advantages, such as ?free advertisement?, simplicity, and other and disadvantages, such as security risks, uncertainty in a legal status, etc. Because of very different approaches to regulation of Bitcoin in different national jurisdictions, therefore this paper is interested in a comparative analysis of a regulation of Bitcoin?s legal status in different national jurisdictions.
Adam Hayes
No abstract is available for this record.
Daniel Bryk Silveira
A revolução tecnológica na área da computação e da Internet trouxe modificações importantes nos mais variados setores da sociedade. Atualmente, a maioria das transações financeiras ocorre virtualmente, nesse contexto surgiu a moeda digital Bitcoin. O conceito desta moeda foi introduzido em 2008 e pode ser descrito como a primeira criptomoeda descentralizada do mundo. As transações em Bitcoin ocorrem sem a necessidade de um intermediário e não dependem da confiança em nenhum emissor centralizado ou instituição financeira. Ao longo deste trabalho serão expostas as características, o funcionamento, as vantagens e desvantagens desta nova moeda, contrastando-a à moeda tradicional de cunho forçado. O objetivo principal é observar se essa nova tecnologia pode ser uma alternativa concorrente aos meios tradicionais, até o ponto de substituir por completo as moedas usadas nos dias de hoje, centralizadas em bancos centrais, ou se a criptomoeda será uma aliada cooperativa à moeda tradicional. Conclui-se que o Bitcoin é no curto e médio prazo uma moeda paralela, ou seja, que coopera e é aliada aos meios tradicionais.
Björn Eriksson
Bitcoin is a cryptocurrency that has been the focus of a lot of discussions lately and has attracted a large number of users. Its offers many possibilities for cheap transactions and unregulated finances which has been realized in numerous sites and applications on the web and in mobile phones. One medium that seem to have been neglected when it comes to Bitcoins development is email. This is curious since Bitcoin by its nature seem to have many properties that would work well with texted messages. The purpose of this study it to analyze the current papers about Bitcoin to find the current status of email based Bitcoin services, and try to analyze if email as a tool is a suitable medium to be used with Bitcoin. This analyze is done through a systematic literature review of current papers, followed by an examination of past and current Bitcoin companies that has used email as part of their service. In the end the results suggested that the low security in email, and the apparent lack of services that would benefit from an email based Bitcoin service suggest that a service like that would be hard to develop today and not very useful to the public.
René Zahrte
Die vorliegende Bachelorarbeit gibt einen Uberblick uber die Funktionsweise und Auswirkungen der Blockchain-Technologie auf den Wertpapierhandel. Dabei werden zunachst die essentiellen, technischen Grundlagen der Kryptografie und Dezentralisierung am Beispiel der fuhrenden Kryptowahrung Bitcoin untersucht. Danach werden die gewonnenen Erkenntnisse mit einer SWOT-Analyse auf den Wertpapierhandelsprozess angewandt und es wird die Implementierung eines Distributed Ledgers auf Chancen und Risiken fur die Finanzmarkte hin evaluiert. Als Essenz der Literaturauswertung ist festzustellen, dass die Starken der DLT nur nach Einigung auf einen technischen Marktstandard voll abgeschopft werden konnen. Die Basis der Bachelorarbeit sind aktuelle Studien und Arbeitspapiere von Regulierungsbehorden, Beratungsunternehmen und Finanzdienstleistern aus Europa und den USA zur Auswirkung der Distributed Ledger Technology auf den Wertpapierhandel sowie die Fachbucher und Arbeitspapiere von Narayanan (2016) und Nakamoto (2008) zur Funktionsweise der Blockchain-Technologie. Durch die Verknupfung von Informationstechnologie und Finanzwirtschaft erhofft sich der Autor einen interdisziplinaren Erkenntnisgewinn uber aktuelle Entwicklungen auf den Finanzmarkten.
Cavidan Yakupoglu
Bitcoin ilk merkezi olmayan, eşler arası ve en çok bilenen kripto paradır. Kripto paralar bir çeşit dijital paralar olup sanal para olarak da adlandırılır. Bitcoin 2009 da kullanılmaya başlandı ve bu tarihten itibaren büyük bir ilgi gördü. Geliştiriciler ve kullanıcılar tarafından büyük yatırımlar ve büyük katkılar sağlandı. Paranın yönetilmesi için bir merkeze bağlı olan günümüzde kullanılan paraya alternatif olarak kullanıma sunuldu. Fakat bu süre zarfında Bitcoin birçok problemle karşılaştı. Bunlara rağmen yaklaşık yedi senede çok büyük bir pazara sahip oldu. Bitcoin'in başarılı çıkışından sonra farklı amaçlara hizmet eden bir çok alternatif kripto para geliştirildi. Geliştiriciler Bitcoin'in bir çok farklı versiyonlarını geliştirdi. Bunlardan bazıları, Litecoin gibi Bitcoin'in kaynak kodunu kullanarak geliştirildi. Bazı kripto paralar Zcash, Ripple, Peercoin Bitcoin'in mahremiyet, ölçeklenebilirlik, enerji tüketimi gibi farklı eksikliklerinin üstesinden gelmek için geliştirildi. Bazıları ise, Ethereum, Namecoin, Colored Coin gibi, blockchain denen herkese açık kayıt sistemi fikrini kullanarak yenilikçi fikirler getirdi. Her geçen gün yeni kripto paralar kullanıma hazır hala getiriliyor ve bu teknoloji gelecekte şu anda kullanılan paranın yerini alacağı tahmin ediliyor. Bu tezde, Bitcoin ve alternatif kripto paralar tartışıldı ve mahremiyet, ölçeklenebilirlik, ticari işlem değiştirilebilirliği ve şu ana kadar maruz kaldıkları, savunmasız oldukları ataklar açısından karşılaştırıldılar. Gelecekteki durumları tartışılarak, gelecekte yapılacak işlerin planı yapılarak bu çalışma tamamlanmış oldu.
Frida Martinsson, Anna Sundberg
Today, most people have heard of Bitcoin, but few have truly understood the concept and its functions. The phenomenon causes strong emotions and the opinions are divided. Some think that Bitcoin will revolutionize the financial system, while others lean towards the possibility that it is merely a short-lived trend. The aim of this report is to analyze if Bitcoin has the qualities required of a substitute for the domestic currency. The study is based on money’s necessary functions and the variables that cause an individual to go as far as abandoning their domestic currency. Even though Bitcoin is a functioning alternative, an analytic comparison with the American dollar showed that bitcoin cannot yet compete with the qualities of dollars, much due to the lack of expansion. The report indicates that in the long run Bitcoin’s characteristics can develop today’s monetary system and create considerable changes in the future.
Juan A. Garay
Distributed consensus (aka Byzantine agreement [Pease, Shostak & Lamport, 1980]) is one of the fundamental problems in fault-tolerant distributed computing and cryptographic protocols. It requires correct participants (parties) to reach agreement on initially held values despite the arbitrary behavior of some of them, with the additional requirement (known as Validity) that if all the correct participants start off with the same value, then that must be the decision value. The problem has been studied extensively in both the unconditional setting (where no assumptions are made about the computational power of the adversary) and the cryptographic setting, and efficient (i.e., polynomial-time) solutions exist tolerating the optimal number of misbehaving parties and running in the optimal number of rounds, on networks with pairwise authenticated channels. In many interesting scenarios, however, such as "peer-to-peer" networks, where parties come and go as they please and there are no prior relations among them, such infrastructure (pairwise authenticated channels, public-key infrastructure) is unavailable, thus raising the question whether anything "interesting" can be achieved. In this talk we answer this question in the affirmative, presenting two new probabilistic consensus protocols based on "proofs of work" (POWs, aka "moderately hard functions," "cryptographic puzzles" [Dwork & Naor, 1992]), the technology underlying Bitcoin, the first and most popular decentralized cryptocurrency to date. (In Bitcoin, POWs are implemented using the SHA-256 cryptographic hash function, by finding preimages that produce values in a given smaller domain.) In more detail, we first extract and analyze the core of the Bitcoin protocol, which we term the Bitcoin backbone, and prove two fundamental properties of its "blockchain" approach which we call "common prefix" and "chain quality." The consensus protocols can then be built as applications on top of the backbone protocol, with the Agreement and Validity properties following from common prefix and chain quality, respectively. The first protocol works assuming the adversary's hashing power is bounded by 1/3 of the network's total hashing power. The second consensus protocol is more elaborate, relies on the notion of robust transaction ledgers, which capture the essence of Bitcoin's operation as a cryptocurrency, and works assuming the adversary's hashing power is strictly less than 1/2.
Richard Thompson Ainsworth, Musaad Alwohaibi, Mike Cheetham
No abstract is available for this record.
Kevin Werbach
No abstract is available for this record.
Eren Yagdiran
Botnets, in other means zombie computers that await for instructions to execute, are the greatest threat in the internet today. They are one of the leading sources of online crime. Criminals are able to take advantage of using botnets and threaten online businesses, organizations or any entity in the internet. Criminals design and implement botnets in a complex way in order to hide their identities. Most notably the fact that criminals build command-and-control (C&C) infrastructures to manage their botnets. A botnet command-and-control mechanism (C&C) can be designed in various ways. The key principle behind designing a C&C mechanism is anonymity. Hence, criminals can propagate their instructions to botnets without revealing their identities. Since every new C&C mechanism increases the bar of anonymity, it is getting harder to trace and analyze botnets. In this thesis, we designed and implemented a C&C mechanism, btc-botnet, that runs over Bitcoin network. Btcbotnet has significant features over existing C&C mechanisms such as anonymity and resistance by its nature. We built a library that allows to use Bitcoin network as an underlying infrastructure for C&C mechanism. We evaluate our work and show that its feasibility in terms of metrics such as response time, confirmation time and fees.
Judyta Przyłuska-Schmitt
No abstract is available for this record.
Jarno Laatikainen
Bitcoin on vuonna 2009 julkaistu vaihdannan väline, jota hallinnoidaan niin kutsutussa vertaisverkossa. Bitcoinin vahvuuksia ovat järjestelmän ulottuvuus, siirtojen edullisuus, helppokäyttöisyys, turvallisuus ja riippumattomuus keskusjohtoisista taloudellisista instituutioista. Bitcoin ei kuitenkaan ole virallinen valuutta, eikä sitä tätä tutkielmaa kirjoittaessa ole juurikaan säännelty eri valtioiden toimesta. Sääntelyn puutteen voidaan katsoa olevan Bitcoin -järjestelmän heikkous, sillä se aiheuttaa epävarmuutta ja epäjohdonmukaisuutta viranomaisten keskuudessa. Vero-oikeudellisesta näkökulmasta sääntelyn puute synnyttää verovelvollisille, eli Bitcoinien käyttäjille riskin odottamattomasta verokohtelusta. \n \nTämän tutkielman pääteemana on Bitcoin -järjestelmän taloudellinen ja verotuksellinen luonne nykyisen kotimaisen tuloverolainsäädännön valossa. Tutkimusmenetelmänä käytetään tietyin painotuksin oikeusdogmaattista ja monitieteellistä näkökulmaa. Soveltuvan oikeuskäytännön rajallisuudesta johtuen keskeisimpinä lähteinä toimivat tuloverolainsäädäntö, lainvalmisteluasiakirjat, viranomaisohjeet ja oikeuskirjallisuus. Tutkielmaa täydennetään taloustieteellisillä lähteillä ja Bitcoin -järjestelmään liittyvällä merkittävimmällä kirjallisuudella. \n \nTutkielman valossa Bitcoin -järjestelmän taloudelliset luonteenpiirteet suhteessa kotimaiseen tuloverolainsäädäntöön näyttäisi asettuvan lähelle omaisuuden luovutusvoittoja ja -tappioita koskevia lainkohtia. Koska Bitcoin -järjestelmän arvo syntyy yksittäisissä vaihdantatapahtumissa subjektiivisesti, ei Bitcoinista saatavaa tuloa tai tappiotakaan voida arvioida sen perusteella, mikä Bitcoinin arvo on suhteessa viralliseen valuuttaan jossain toisessa vaihdantatapahtumasta. Nykylainsäädännön valossa Bitcoin tulisi määritellä omaisuudeksi tai toissijaisesti rinnastaa sen kohtelu omaisuuden luovutusvoittoverotukseen. Näin tuloverotuksessa päästäisiin mahdollisimman lähelle Bitcoinin taloudellisia realiteetteja. Tällainen Bitcoinin tuloverotuksellinen kohtelu vastaisi lisäksi verovelvollisen todellisia maksukyvyn muutoksia ja täyttäisi hyvän verojärjestelmän edellytykset verotuksen oikeudenmukaisuudesta ja neutraalisuudesta.
Dominick j Battistini
Money laundering can be defined as any act or attempted act to conceal or disguise the identity of illegally obtained proceeds so that they appear to have originated from legitimate sources (Money Laundering, 2016). It is difficult to determine the magnitude of money laundering because these illicit financial flows remain hidden (Schott, 2006). A report issued by the United Nations Office on Drugs and Crime (UNODC) quoted that the total of all criminal proceeds amounted to $2.1 trillion in 2009. The study also shows that “Less than 1 percent of global illicit financial flows are currently seized and frozen” (Pietschmann & Walker, 2012). This is concerning because money laundering not only enables the operation of criminal organizations such as drug and human traffickers but can also significantly distort the economies in which they enter.\nThe Financial Action Task Force (FATF) is an inter-governmental policy-making body that has helped to promote anti-money laundering efforts since its formation in 1989. It has issued 40 recommendations to fight money laundering and nine special recommendations to combat terrorist financing which have been adopted by 32 countries (About - Financial Action Task Force, 2016). Unfortunately, implementing these strategies has proved to be difficult for both developed and lesser developed countries. According to a study conducted by PricewaterhouseCoopers in 2016, “over the last few years, in the U.S. alone, nearly a dozen global financial institutions have been assessed fines in the hundreds of millions to billions of dollars for money laundering and/or sanctions violations" (PricewaterhouseCoopers, 2016). It stands to say that if financial institutions are having difficulties implementing frameworks to prevent and detect money laundering, then our enforcement agencies are unable to adequately address the issue as well.\nA new hurdle that enforcement agencies have had to face is the emergence of Bitcoin, as well as other cryptocurrencies, that can be described as “a digital currency and online payment system in which encryption techniques are used to regulate the generation of units of currency and verify the transfer of funds, operating independently of a central bank” (Swan, 2015). Being an often unrecognized currency, many banks and financial institutions have not had to worry about modifying their compliance programs. The biggest benefit of cryptocurrencies to money launderers is its decentralized nature. There is no governing authority, as members of the network handle issuances and payments. Once a disruptive technology, Bitcoin is beginning to lose momentum for a number of reasons and some its strongest proponents are now referring to it as nothing more than an experiment. The purpose of this paper is not to examine Bitcoin, but rather its underlying technology that has been found to be the actual value: blockchain. After providing a brief overview of the technology and the hurdles that financial institutions face when implementing anti-money laundering compliance programs, the possible ways in which blockchain can help alleviate these difficulties will be examined.
Aggelos Kiayias, Hong-Sheng Zhou, Vassilis Zikas
No abstract is available for this record.
F. Xavier Olleros
No abstract is available for this record.
Kartik Hegadekatti, S G Yatish
In this paper, we analyse the workings of commercial banks in a scenario where crypto-currencies are the mainstream bills of exchange. We start by explaining the concept of cryptocurrencies (also referred to as cryptocoins in this paper). Then we discuss the concept of Regulated and Sovereign Backed Cryptocurrencies (RSBCs). Later on, we envisage a scenario where cryptocoins are the main media of exchange. The banking aspects of Paper money, Bitcoins and RSBCs are then deliberated. We analyse the interplays between Banking and various currency formats. Finally, the paper concludes as to which currency is best suited to be the mainstream bill of exchange.
Allison Caffarone, Meg Holzer
July 22, 2016. A Florida state court dismisses a three-count information against a sole defendant in "a Miami money-laundering case that is being closely watched around the world." The defendant, a dealer of the virtual currency bitcoin, is free to go. He is also free to continue engaging in the sale of bitcoin. This "victory for bitcoin users" was the first state court case to address Bitcoin in the context of the money services business and anti-money laundering statutes. And on every front, the court got it wrong — while the world was watching. Federal and state prosecutors, defense attorneys, judges, and the Bitcoin community paid careful attention to the case. And although the opinion is not binding, it must be given its "proper regard." The Little Case That Could has effectively become the Little Case That Shouldn't. Two avenues must be pursued to correct the problems with the Espinoza court's findings. First, a Florida appellate court must overturn the decision on appeal. Second, the legal and financial communities must, as the Southern District of New York already has, disregard the Espinoza court's ineffective reasoning as they continue to develop the law of Bitcoin. Because while this Florida state case awaits appeal, and is not binding on any court, it remains persuasive authority in an area of law where few cases have directly analyzed the character of Bitcoin. As the law is in a constant state of growth, a trial court order opining on this topic has the possibility to cause damage. What exactly did the court do — and decline to do — when it dismissed the charges against Espinoza? And why is this state court dismissal of these charges against a sole defendant so potentially troubling across the world? To answer these questions, we first must turn to the currency (or is it?) at the center of the case: bitcoin. Part I of this article seeks to explain in largely non-technical terms the design of the Bitcoin network. Part II explains the guidance and administrative rulings provided by the United States Department of the Treasury's Financial Crimes Enforcement Network in relation to the issues in the Espinoza case. Additionally, Part II surveys different approaches taken by state legislatures and regulators in seeking to address decentralized virtual currencies, including bitcoin. Careful attention is paid to how the terms "monetary value" and "virtual currency" are defined, and how those definitions have been interpreted. Part II further explores the differences in the way the respective laws and guidelines treat different members of the Bitcoin ecosystem. Part III analyzes the Espinoza case, taking a critical look at the reasoning behind the dismissal of the criminal information, and suggests that the court's holdings are analytically unsound. Finally, we argue that the Espinoza case must not be allowed to stand and needs to be reversed on appeal.
Fabio Massacci, Chan-Nam Ngo, Julian Williams
Blockchains and Byzantine Fault Tolerance form the basis of decentralized currencies and ledgers such as Bitcoin, Ripple, ZeroCash, and Ethereum. A large slate of literature has focused on the currency aspects (e.g. anonymity, independence from central banks, etc.). We argue that, as-far-as Distributed Payment Transactions Networks (PTNs) are concerned, there are other, possibly more interesting, properties. This paper provides a systematic review of both traditional PTNs and their analogues in decentralized ledgers and associates different technological features to the corresponding business and financial requirements. We provide a conceptual classification of the key properties (value creation, payment promise, transaction fulfillment, and value preservation). We map existing (distributed) PTNs into the classification showing different alternatives are possible. Furthermore, the ideas behind distributed ledgers can be extended beyond payments and contracts. We illustrate the idea of derivatives-contracts-as-programs that are marked to market (or an account that is margined) automatically by computations run on, and whose ownership transitions are recorded, in a distributed payment network.
Gina Pieters
No abstract is available for this record.
Giuliano Lemme, Sara Peluso
parte di due revisori con il sistema del doppio cieco.
Belkenia Candelario
Esta nota se tratará el tema de Bitcoin, la criptomoneda líder que surge en el año 2009 como una alternativa a la moneda fiduciaria. Bitcoin ha crecido considerablemente, tanto en términos de valor como en la conciencia colectiva internacional; sin embargo, los anuncios y regulaciones exploradas afectarían a todas las monedas digitales en general. Primero, esta nota explica el concepto tecnológico y funcional detrás de Bitcoin en términos de fácil acceso para el usuario y proporciona una breve discusión teórica sobre la historia de la aparición del dinero en el comercio. Segundo, analiza algunos de los efectos que tendría la regulación de Bitcoin y otras criptomonedas empezando con un análisis de los anuncios creados por agencias y departamentos federales de los Estados Unidos, continúa con un análisis de las regulaciones estatales de California, Texas y Nueva York. Se examina los componentes más importantes y las implicaciones que puedan tener sobre el uso de Bitcoin. Además se exploran otras leyes que han sido promulgadas en América Latina por Bolivia, Brasil, Colombia y Ecuador para regular el uso de las monedas digitales.
Bart Custers, J.J. Oerlemans, Ronald Pool
No abstract is available for this record.