Blockchain Papers

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US bitcoin technology firm Case has launched its bitcoin with multifactor security incorporating fingerprint biometrics. The standalone device is about the size of a credit card.

Greg Anderson

Greg Anderson is an Associate Professor of History at Ohio State University, where he has taught since 2005. His teaching and research cover ancient Greece, critical theory, and historical thought. In his first book, The Athenian Experiment: Building an Imagined Political Community in Ancient Attica, 508–490 b.c. (University of Michigan Press, 2003), and a number of other pieces, he questions the use of modern categories such as “state,” “tyranny,” and “democracy” to characterize phenomena in ancient Greek experience. He is currently working on two book projects: a monograph, The Realness of Things Past: Ancient Greece and Ontological History, and a volume of essays on states in history titled State Formations: Histories and Cultures of Statehood, which he is co-editing with John Brooke and Julia Strauss. The Decree of Eukrates (337/6 b.c.). This decree authorizes Athenians to assassinate anyone who attempts to establish a tyranny in the polis of Athens and prescribes punishments for any would-be collaborators. The sculpted relief shows Demos (“the People of the Athenians”) being crowned by a personified Demokratia. As the image suggests, the Athenians conceptualized Demos as a unitary corporate person, not as an aggregate of autonomous individual persons. In contemporary thought and practice, this corporate self was a kind of primordial superorganism, one that existed prior to and apart from the particular flesh-and-blood Athenians who happened to embody it at any given time. As “the rule of Demos,” Athenian demokratia was thus not just institutionally different from modern individualist democracies. It was premised upon entirely different ontological foundations. Athens, Agora Museum I 6524. American School of Classical at Athens: Agora Excavations. Photo: C. Mauzy. Our discipline's grand historicist project, its commitment to producing a kind of cumulative biography of our species, imposes strict limits on the kinds of stories we can tell about the past. Most immediately, our histories must locate all of humanity's diverse lifeworlds within the bounds of a single universal “real world” of time, space, and experience. To do this, they must render experiences in all those past lifeworlds duly commensurable and mutually intelligible. And to do this, our histories must use certain commonly accepted models and categories, techniques and methods. The fundamental problem here is that all of these tools of our practice presuppose a knowledge of experience that is far from universal, as postcolonial theorists and historians such as Dipesh Chakrabarty have so well observed. In effect, these devices require us to “translate” the experiences of all past lifeworlds into the experiences of just one lifeworld, namely a post-Enlightenment “Europe,” the world of our own secular, capitalist modernity. In so doing, they actively limit our ability to represent the past's many non-secular, non-capitalist, non-modern “ways of being human.”1 To be sure, the discipline's cultural turn of the last thirty has us to the of non-modern our of past and the have us to the of our with the of and cultural history has us to that our non-modern in its it a knowledge of one that for a primordial and a and the one to represent that it is a historicist that us to the experiences of To the a by the a of and and in they by own on the of the as as one attempts to this to tell a in the by our discipline's and one the ability to the here by The one can do within the limits of our is to to the and of cultural to it as the of his who can be the the to a history of the one that to a the of the as it was by the the of to an of to a of it past. It that past into the past of namely our that the of past all those of the lifeworlds that by the the postcolonial of has for our as of historians have to as the of historical knowledge us to non-modern experiences by all into modern the of in is the To have on and a has to Our be to ontological which to be we can our of and non-modern we to the of To us all those that we have in we a that can of non-modern on its own ontological as a world in its own and to ontological experience. past of its own particular its own of the of its own particular of and and and and and so our historicist categories, and do not us to past experiences all the to the ontological they require us to non-modern lifeworlds as all within one and the within a single universal by of and a where and individualist The is a practice that the of non-modern past the to the of own experience. the of and that the of this historicist practice far they a these have and by of thought in a of from and critical to and on the of these we can in turn to an one that in an entirely not as an as a as an by the of thought and this of require us to an ontological turn in our It us to of past in its own our non-modern was in be an of was at the And we to this we duly histories that at and As a lifeworld, Athens can as a for the us to in an ontological turn in historical of at and a of ontological In to in and upon the world as a the of any given historical must that world as a must a knowledge of is of the and of which that world must a of the phenomena that the and of phenomena those we and and and and and the and of And they of in the all and upon the of such a and In other past and for and to its own particular its own of it to be the is to have in not just To this we have to the world of our own capitalist which on at ontological and is The and other upon which modern being is all presuppose a a world in which is to those phenomena that with our of and As our world has for it as and It is thus a world entirely of all the and and and and the other that have and all other historical for It is a world where is a world of and and all those from to the to and from the It is a world that has all those that and and It is a world this it of that modern is as it the of at it as of the and of as of and not as in own It thus all and the that to a of experience a that is from the of This of a of well to those who have to of as a of the of it have at all in non-modern where was in all of where have the who it of is a that in our modern a world that is secular, a world where have from into that they have the and the to of And this us to the commitment of our modern which is its who of the of within a of a of own have about upon the of his capitalist is upon an of The of experience is thus into two mutually an of knowledge and and to be from a of from a of and And with this of have world from not all non-modern have from of being by the of the and the by the of and from who the that in as from who it for that and in and all the modern ontological that be to non-modern be those we and other persons. we to the and last of the ontological that capitalist namely our our that all This ontological have the of where the the of the was “the of of the and thus the in his own person, as a of his own such that his all of the It have for that in the world of where and as the and of a single primordial And the of a individual be and the of who all as as of all the and of that have in the modern capitalist it as the primordial of the that all with a to a and upon our to and thus to of of and so as not as of our of who we as And we that being to individual the other we that individual in the first who our us to at any given the of a this of and any be to and the to it is by a since it to rule to other who rule for must be by such as and “the of on the of to on to a of must be from the of by of and other such And in our modern world it entirely that not the of that we the of our be from any In our world it to the to all of for the tools of historicist practice to the ontological of past experience. they us to modern upon all non-modern To the we can to Athens, a non-modern lifeworld, and the Athenian of that has us of the Athenians to be the of it the Athenians not of to tell was and was was in the stories they about and in all and it was far and our was premised upon just a and the two in the of Attica, not just The Athenians with and other polis was with “the and not just of and in the world of and space, who all of and the in Athens not for the of the in Athens was the of of and And and to and from and to and the Athenians to in on just so with and a of in Athens was not a of to It was all about those to and the of the polis as a The of Athenian being was the of In the of the was not of It was a a that was at and and To since the Athenians to be an who since the was to be a a of to by they as as a with they an Attica, they given to the first such as and who from As the first on to of and these first to to as and to Athenians in all the to And just as as “the of so the Athenians as as the of and by and from of all of Attica, of duly the of the they not do so as a aggregate of and they in the world as a corporate person, a they “the People of the As the of the polis this unitary Demos was a kind of primordial that in since the of those first It thus existed prior to and apart from the particular who happened to and embody it at any given in this Demos was not a of It was about a the of a a polis which an individual have and about the primordial of Greek polis well by The polis is by prior to the and the since the is of prior to the for the is be in the that we of a for the be that The that the polis is a of and prior to the individual is that the is not and he is a in to the he who is to in has he is for must be a a he is of the to modern the of the Athenian not these for the of from the of Attica, which was conceptualized as a for not as the of a Athenian as by a with the that they being within Athenian not one an Athenian and one the to in the one an Athenian was being into the of Demos an Athenian who and of the of the As for the of those to the of the Athenians that the and to and Athenian was in a its as its and in the He duly with his other the for and the of the as a as who one to into not such in the polis was to the of Demos by and within its the polis and in Athens, the Athenians and the it be to of as a Most immediately, one was a a of the and an a of a particular In our modern it is as they all two different at the time, with its own of And of is to Athenians just for as as of a universal the world as of a particular as of the polis and the that and in the first and polis they the that they an Athenian different from all other Greek and In the world of the Athenians was premised upon a just a of and the in this was to the of for and the of was to the of for and The was to and these in such a that the be and that the be and that they a the of the as a And they This of is they It to do with “democracy” as we the It was Demos to do to its own in its particular where upon with in the of from other In demokratia was the of and in and upon the world to the of the This be in it be in the in at on the Athenians to as one in the unitary of the polis so they in as and other as as of the of the As these Athenian and with for a of any it is demokratia in it is not demokratia to to Greek historians of that the Athenians to own all those just we we to use models and categories, tools that actively this non-modern to our own modern ontological tools first of to a modern of ontological us to that the of Athens, the of all to be in a of the the and the they us to that the Athenian and other a of “state,” an that was from a Athenian that these two mutually categories do not to phenomena in ancient experience. it is Athenian was entirely by by of Athenian we that the polis of Athens must have kind of of and the that us to 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for where the of by where as a rule for the Athenians have the of an such as and they have these to be all for to in the was not a a that be by of was the primordial upon which the of all Athenians since was a of the the and the of the the Athenian on its own in this us to for that the in the polis those the and the and the for such as and to the to the of the the time, this us to the many by to Athenian own to into Athenian not just the the of an to the of within that with the for and that Athenian to as in the first And it us to the of the as a to upon the by the of As the of the polis of these to a for its to use and to and the of Demos on a And with duly such was for Demos to its In this of the of and to the of the polis us to any use of the modern and in our of the Athenian as these we to that Athenian demokratia an the corporate self of Demos and its the of the and the of its it was for in Athens that and all of from of and to and to Demos which by the Athenians to any of with a a of In Athens, it have to from the upon which they all and which they all and the the polis and its to that the of a particular a and was as a to the of the polis as a And of it to it to the Athenians that all in the and be by not by was a in Athens a and the of its it was thus not a in the of experience any of and It was a within the of a and an a that that Athenian to be in different a particular of a particular and a of the Demos we to that Athenian demokratia to do with individualist and and to do with corporate by a of our with other modern categories, and And we such categories and to of the Athenian on its own we can that all those of of our own Athenian not of the polis to of our own individualist of in Demos in Athens have to any As the of Attica, as of in and as and of as and who and the of the Athenians as to the of Demos as that to that be not was the and demokratia as the Athenians the This the in of who the and Demos and of in the to Athenians in the to as and and for the and and to and the of the In other demokratia was entirely those who the to such as the of to the of Demos with Athens and its demokratia by these not by and Athenian demokratia was in a in corporate not an in the of as and to In an where for not for the of the was the of a in have any And as we have Athens have many of the and cultural to The was to the from the of other the of which is the Athenians in the of the the Athenian was the of this to lifeworlds at a certain Most an ontological turn require us to our with its of and all its of a unitary experience in a single It the that has the the and other to this practice of the ontological from which different have the past's many of and of and so And this is the that we have to for histories that at and it to be well this of the for our modern that the ontological of experience to the of lifeworlds that have

Christian Jaag, Christian W. Bach

Contrary to traditional currencies, cryptocurrencies neither have physical form nor are they guaranteed or backed by any central authority. They simply attain value by usage and the confidence of those participating in the respective system. A crypto-paymentsystem is a technology which allows for payments between individuals digitally without relying on central institutions, intermediaries or further infrastructure as required for conventional payment systems. While its legitimacy as currency has been questioned due to its high exchange rate volatility, the significant potential of the Bitcoin technology as a payment system is undeniable. As postal operators typically have a role as financial intermediaries and act in an inter-national and increasingly digital environment, crypto-paymentsystems may be of particular interest to them. In fact, as the post has a wide network of access points and is highly trusted by the general public, it may be well-suited to offer services which counter some disadvantages of crypto-paymentsystems and cryptocurrencies, while retain-ing the benefits of their technology. By turning to crypto-paymentsystems postal operators may extend their role as a financial intermediary with new domestic and interna-tional services. Furthermore, postal operators may even issue their own cryptocurrency to protect customers from the high exchange-rate volatility of cryptocurrencies.

Anna Wiśniewska

The aim of this article is to show the position of Bitcoin among virtual currencies. On the basis of the reports published by the European Central Bank and The Financial Action Task Force, as well as the available Internet and primary sources, there have been presented the types and the history of virtual currencies, the way in which Bitcoin functions and the methods of acquiring it. The article is based on the assumption that an in-depth knowledge of virtual currencies, their classification and their functioning will make it possible to regulate their legal status. It is necessary not only for tax purposes, but also in order to avoid the risk of using this payment method for terrorist or criminal purposes. The knowledge of the history of virtual currencies also makes it possible to foresee the problems that may hinder the functioning of Bitcoin and other virtual currencies. The growing popularity of virtual currencies and cryptocurrencies is linked with the increase of importance of non-cash payments on global scale. Thus, Bitcoin may be considered a next step in the evolution of digital money.

Cristianne Maria Famer Rocha, Silvia Helena De Bortoli Cassiani

In recent decades, health care networks in diff erent parts of the world have incorporated new forms of social organization that involve extensive use of technology to produce and disseminate information and are based on the autonomous, non-hierarchical and decentralized cooperation and collaboration of those within these networks. In Latin American countries, Nursing Networks were created in the 2000s on the initiative of professionals seeking to exchange knowledge and experiences. Over time this initiative gained ground with the support and leadership of the Regional Council for Nursing and Health Technicians of the Pan American Health Organization (PAHO) and, in 2007 and, in 2007, the 1 st International Nursing Network Conference was held in Toledo (Spain), during the 9 th Ibero-American Conference of the Latin American Association of Nursing Schools (ALADEFE). These networks operate as a communication strategy, stimulating cohesion and cooperation between nurses interested in developing nursing care, management, research, information and education with a view to supporting the advancement of the profession and help countries achieve universal health care coverage and access to health services. There are currently around 25 International Nursing Networks in the Americas, which together form Rede EnfAmericas and consist of more than 3000 nurses in Latin America. Information on each of these networks is available at: http://www.

Gerry Braun, Stan Hazelroth

Transitioning to clean, climate-friendly and smarter electricity systems means bringing innovative, capital-intensive, and increasingly decentralized power sector infrastructure on stream. National, state, and local policy should recognize and address the implications for finance , particularly the need for investments that capture and optimize local economic benefits.

Jamal Bouoiyour, Refk Selmi, Aviral Kumar Tiwari

The present study addresses one of the most problematic phenomena: Bitcoin price. We explore the Granger causality for two relationships (Bitcoin price and trade transactions; Bitcoin price and investors' attractiveness) from a frequency domain perspective-based on unconditional and conditional data analysis. Accurately, this research empirically assesses the causal links between these variables unconditionally on the one hand and conditioning upon relevant control variables (recorded in literature) on the other hand. The observed outcomes reveal some differences with respect to the frequencies involved, highlighting the difficulty to reach clearer insights and better paths into this nascent crypto-currency. Beyond the nuances of short-, medium- and long-run frequencies, this paper confirms the extremely speculative nature of Bitcoin without overlooking its usefulness in economic reasons. The consideration of the Chinese market index, the hash rate, the monetary velocity and the estimated output volume has led to solid and meaningful findings connecting further Bitcoin to speculation.

Young-Aa Ryoo, Pildoo Kim

No abstract is available for this record.

Victor Ranieri Bomfim Sampaio de Araújo, Márcia Reis Machado Machado

Bitcoins are in use today to do transitions. There are companies that accept Bitcoins as payment whem supply goods and services. However there isn’t currency status. It’s made of mathematics equations that its transactions are validated through encryption, hash function, p2p network and proof-of-work. Like a currency that just exists in the virtual form it needs the user’s confidence for have a valour. Although the large growth since your creation, in 2008, and be considered for many a big evolution, in the informatic and business fields, some entities and researchers say the Bitcoins are a ponzi scheme. This research aims to describe the transitions that envolve cripto-currency and the suitable accounting treatment in Brazil, based on the current standards. For this was done a general analysis that shows the best classifications as Contingent Asset, because their uncertainty value and their uncertainty existence too. The second section of the analysis was done hypothetical situations. The first was the mining situation, then the receive bitcoins as payment and finished with the company had bought that. Because it’s a Contingent Asset was generated a conflict on the two last situations. But for that was suggested an account on the current asset that represent the expectative to generate future cash flows when liquidate the Bitcoins without excluding the disclosure in the notes as Contingent Asset. Lastly was concluded that the risks associated with property losses and the association with illicit activity, beyond that there are so many indications that is a ponzi scheme and even it isn’t, there are not perspective for their operation.

Myungsun Kim, Bolam Kang

본 논문에서는 미리 알려진 임의의 다항식과 암호화된 다항식의 곱셈을 수행한 후, 해당 곱셈이 정당하게 수행되었음을 보이기 위해 증명자 (Prover)와 검증자 (Verifier)간의 다항식 상등성 영지식증명 (Zero-knowledge Proof) 프로토콜을 일반화할 수 있는 방법을 다룬다. 이를 위하여 다항식의 상등성을 증명하는 일반화된 프로토콜을 제시하고 랜덤오라클 (Random Oracle) 모델에서 안전성을 증명한다. 이러한 기법은 안전한 집합연산 기법을 포함하여 다항식에 기반한 다자간 연산기법 (Secure Multi-party Computation)에 적용될 수 있다. In this paper, we are interested in a generalization of zero-knowledge interactive protocols between prover and verifier, especially to show that the product of an encrypted polynomial and a random polynomial, but published by a secure commitment scheme was correctly computed by the prover. To this end, we provide a generalized protocol for proving that the resulting polynomial is correctly computed by an encrypted polynomial and another committed polynomial. Further we show that the protocol is also secure in the random oracle model. We expect that our generalized protocol can play a role of building blocks in implementing secure multi-party computation including private set operations.

Przemysław Szetela

The main purpose of this article was to present the most important organizational, supervisory and financial competences of local government units (LGUs) in Poland relating to public health care institutions (medical entities, a non-entrepreneurs). One of the goals of article was also evaluated the involvement of the various levels of local government in Poland in the financing of the tasks related to the health care and evaluated the effects of decentralization in health care. The article has been prepared on the basis of literature study, including the current legislation, as well as papers of various organizations, institutions and scientific journals.

Shiret Elezi

Local Government finance is of immense importance for a state and for the government functions of rendering services to the citizens. Local finances reflect the fiscal independence of municipalities and the financial capacity to carry out its responsibilities under the legal provisions of the central government. It is therefore very important to monitor the development of local finance in transition countries and in transferring experiences from countries with higher fiscal decentralization to countries which are pre-accesion candidates to EU. Countries with higher fiscal decentralization are more acceptable bycountries that are recently new members of the European Union under similar region. In this study, a parallel overview of the local finances of new member country in the EU, Slovenia and pre-accesion candidate country to the EU i.e. Macedonia, was taken

Benoît Libert

This habilitation thesis deals with cryptographic primitives that preserve the algebraic structure of underlying objects (messages, keys, etc) and their applications to the design of non-interactive zero-knowledge proofs and privacy-enhancing cryptographic primitives.In 2008, Groth and Sahai showed how to make these proof systems relatively efficient in abelian groups endowed with a bilinear map. These techniques, however, require to work with lower-level primitives where handled objects all live in a cyclic abelian group. Among other things, we need to sign messages without destroying their algebraic structure (in particular, without hashing them first) so as to be able to efficiently prove properties about hidden signed messages. The first part of this thesis describes a structure-preserving signature scheme which was the first efficient realization under previously studied algorithmic assumptions. These tools are also utilized in the design of a novel revocation mechanism for group signatures, which allow users to anonymously sign messages on behalf of a population they belong to. The second part of this thesis considers structure-preserving signatures endowed with homomorphic properties. We show how to use them in the design of non-malleable cryptographic primitives. Using linearly homomorphic structurepreserving signatures, we notably obtain non-malleable commitments to group elements and non-interactive zero-knowledge proofs, as well as public-key encryption schemes that resist chosen-ciphertext attacks.

Todd J. Barre

The emergence of Bitcoin as an online currency/payment system has been surrounded with controversy with equally passionate proponents and detractors arguing for its long-term viability. These debates lead to stimulating exercises for the finance or economics student eager to understand principles of money, currencies, and monetary economics. The author presents a summary of the key arguments in a pedagogical structure useful to instructors who wish to use Bitcoin as a practical tool to stimulate critical thinking on these topics in the college classroom.

Hanna Hałaburda, Miklós Sárváry

In this chapter, we discuss economic aspects of cryptocurrencies. 4.1. The double spending problem 4.2. How does Bitcoin work? Brief overview 4.3. Not the first one – predecessors of Bitcoin 4.4. Problems with Bitcoin (new challenges) 4.5. Competition against other crypto-currencies 4.6. Non-currency use of blockchain technology 4.7. Trading cryptocurrencies 4.8. How do crypto-currencies’s attributes compare to earlier money? For Chapter 1 (Introduction), see https://ssrn.com/abstract=3135021. For Chapter 2 (Means of Exchange: Ever-present Competition), see https://ssrn.com/abstract=3135028. For Chapter 3 (Platform-based Currencies), see https://ssrn.com/abstract=3135030. For Chapter 5 (Conclusions), see https://ssrn.com/abstract=3135057.

J-C. Leneveu, A. Chereau, L. Mansart, T. Mesbah · 5 authors

No abstract is available for this record.

Vincent Van Mieghem, Johan Pouwelse

This paper describes the process of remaining anonymous online and its concurrent operational security that has to be performed. It focusses particularly on remaining anonymous while purchasing online goods, resulting in anonymously bought items. Different aspects of the operational security process as well as anonymously funding with cryptocurrencies are described. Eventually it is shown how to anonymously purchase items and services from the hidden web, as well as the delivery. It is shown that, while becoming increasingly difficult, it is still possible to make anonymous purchases. Our presented work combines existing best-practices and deliberately avoids untested novel approaches when possible.

Tjaša Bjedov

This PhD thesis falls within the fields of public finance and public choice. It studies the following issues: ideological polarization, decentralization and conflict. It consists of three chapters can be read independently. In the first chapter the focus is on the importance of ideological polarization between but also within political parties on the level and composition of cantonal public spending. The analysis is on Swiss cantonal parliaments and is based on the use and econometric treatment of a very rich database. We made two contributions to the literature on the impact of political fragmentation on public spending. First, we showed that ideological dispersion within political parties is associated with higher public spending while the dispersion between political parties is associated with less public spending. This finding implies that the mode of organization and discipline within political parties are both important. This result is particularly interesting given that previous literature has completely abstracted from ideological dispersion within political parties. Lastly, we showed that ideological dispersion between and within political parties is mainly relevant for current expenditures. The second chapter focuses on the conflict of objectives that may exist between economic agents in a two-stage game with asymmetric payoffs. The literature showed that coordination failures are frequent in one-stage games and that communication can help individuals coordinate with the use of take turn strategies that allow for a reduction in the payoffs’ inequality in the long run. Our contribution was to study whether communication has the same capacity in a two-stage game where the subgame perfect Nash equilibrium requires both players to make opposite choices at both stages of the game and accept unequal payoffs. Our results show that coordination failures occur half of the time and that 18% of the pairs use the take turn strategy. Communication significantly increases coordination on the subgame perfect Nash equilibrium because it increases the ability of subjects to initiate a take turn strategy and to maintain it. Thus, communication allows subjects to establish a long-term strategy that increases efficiency and reduces payments differences, induced by the asymmetry in payoffs, by exchanging their relative positions in a fair way. Our results show that communication can solve coordination conflicts, even in more complex situations than in one-stage games usually studied until now. The last chapter focuses on a particular type of conflict: political secessions. Specifically, it addresses the link between secessions, decentralization and group identity. We aim at determining, by means of a laboratory experiment, if decentralizing the provision of public goods reduces the likelihood of secession. We emphasize the importance of local identity. Our experimental design, obviously, do not reproduce all the trade-offs that separatist movements face in the real world. It allows, however, capturing at least two key forces that drive these movements: the proximity to public goods that reduces the phenomena of free-riding and brings public goods closer to citizens’ preferences and the importance of local identities. Our results indicate that the Decentralization treatment increases contributions to local public goods and decreases the likelihood of secessions also when identity is made more salient. If fact, reinforcing local group identity increases the likelihood of secession only when local group members are cooperators.

Ghassan Karame, Elli Androulaki, Marc Roeschlin, Arthur Gervais · 5 authors

Bitcoin is a decentralized payment system that relies on Proof-of-Work (PoW) to resist double-spending through a distributed timestamping service. To ensure the operation and security of Bitcoin, it is essential that all transactions and their order of execution are available to all Bitcoin users. Unavoidably, in such a setting, the security of transactions comes at odds with transaction privacy. Motivated by the fact that transaction confirmation in Bitcoin requires tens of minutes, we analyze the conditions for performing successful double-spending attacks against fast payments in Bitcoin, where the time between the exchange of currency and goods is short (in the order of a minute). We show that unless new detection techniques are integrated in the Bitcoin implementation, double-spending attacks on fast payments succeed with considerable probability and can be mounted at low cost. We propose a new and lightweight countermeasure that enables the detection of double-spending attacks in fast transactions. In light of such misbehavior, accountability becomes crucial. We show that in the specific case of Bitcoin, accountability complements privacy. To illustrate this tension, we provide accountability and privacy definition for Bitcoin, and we investigate analytically and empirically the privacy and accountability provisions in Bitcoin.

Gabrielle Durana

Échapper aux banques : une utopie qui a retrouvé de sa vigueur au lendemain de la crise des subprime et a donné naissance au « bitcoin », une monnaie numérique sur laquelle ont très vite commencé les spéculations, financières et autres. Mais quelle est la portée réelle de cette invention ?

George Danezis, Sarah Meiklejohn

Current cryptocurrencies, starting with Bitcoin, build a decentralized blockchain-based transaction ledger, maintained through proofs-of-work that also serve to generate a monetary supply. Such decentralization has benefits, such as independence from national political control, but also significant limitations in terms of computational costs and scalability. We introduce RSCoin, a cryptocurrency framework in which central banks maintain complete control over the monetary supply, but rely on a distributed set of authorities, or mintettes, to prevent double-spending. While monetary policy is centralized, RSCoin still provides strong transparency and auditability guarantees. We demonstrate, both theoretically and experimentally, the benefits of a modest degree of centralization, such as the elimination of wasteful hashing and a scalable system for avoiding doublespending attacks.

Ekaterina Mikhailovna Taran, Irina Pavlovna Salmanova, Elena Viktorovna Dokukina, Margarita Arkadevna Menshikova · 5 authors

The article highlights the issues of emergence and existence of cryptocurrency. Exploring online space, you canselect the most popular existing electronic currency which is bitcoin (Bitcoin). The article analyzed the pros andcons and the legality of these

Nicolas Xavier Zavaleta

No abstract is available for this record.

Denis Buterin, Eda Ribarić, Suzana Savić

No abstract is available for this record.