Regio A. Michelin, Ali Dorri, Roben Castagna Lunardi, Marco Steger · 7 authors
There is increased interest in smart vehicles acting as both data consumers and producers in smart cities. Vehicles can use smart city data for decision-making, such as dynamic routing based on traffic conditions. Moreover, the multitude of embedded sensors in vehicles can collectively produce a rich data set of the urban landscape that can be used to provide a range of services. Key to the success of this vision is a scalable and private architecture for trusted data sharing. This paper proposes a framework called SpeedyChain, that leverages blockchain technology to allow smart vehicles to share their data while maintaining privacy, integrity, resilience and non-repudiation in a decentralized, and tamper-resistant manner. Differently from traditional blockchain usage (e.g., Bitcoin and Ethereum), the proposed framework uses a blockchain design that decouples the data stored in the transactions from the block header, thus allowing for fast addition of data to the blocks. Furthermore, an expiration time for each block to avoid large sized blocks is proposed. This paper also presents an evaluation of the proposed framework in a network emulator to demonstrate its benefits.
This article evaluates the legal framework of cryptocurrency in various countries. The new currency instrument is abstract currencies. They are currencies in the sense that they can be exchanged peer-to-peer. They are representations of numbers, i.e. abstract objects. An abstract currency system is a self-enforcing system of property rights over an abstract instrument which gives its owners the freedom to use and the right to exclude others from using the instrument. Cryptocurrency or virtual currency is a cryptographically protected, decentralized digital currency used as a means of exchange. Due to the development of new technologies and innovations, the rate of use of virtual currency is rapidly increasing throughout the globe, replacing not only cash payments and payments by bank transfer, but also electronic cash payments. Among the best-known representatives of cryptocurrencies are Bitcoin, Litecoin and Ethereum. Legal scholars have not yet reached a consensus regarding the nature and legal status of virtual currency. Virtual currency possesses the nature of obligations righ ts as well as property rights, since it may be both a means of payment and a commodity. Depending on the country, the approach to cryptocurrencies may be different. Today there is already an international cryptocurrency community that does not have a single coordinating center. Only progressive jurisdiction and state regulation of cryptocurrency activity will allow the creation of the conditions that will ensure the implementation of legitimate and safe cryptocurrency relations.
Decentralized Ledger Technology, popularized by the Bitcoin network, aims to keep track of a ledger of valid transactions between agents of a virtual economy without a central institution for coordination. In order to keep track of a faithful and accurate list of transactions, the ledger is broadcast and replicated across machines in a peer-to-peer network. To enforce validity of transactions in the ledger (i.e., no negative balance or double spending), the network as a whole coordinates to accept or reject new transactions based on a set of rules aiming to detect and block operations of malicious agents (i.e., Byzantine attacks). Consensus protocols are particularly important to coordinate operation of the network, since they are used to reconcile potentially conflicting versions of the ledger. Regardless of architecture and consensus mechanism used, resulting economic networks remain largely similar, with economic agents driven by incentives under a set of rules. Due to the intense activity in this area, proper mathematical frameworks to model and analyze behavior of blockchain-enabled systems are essential. In this paper, we address this need and provide the following contributions: (i) we establish a formal framework, with tools from dynamical systems theory, to mathematically describe core concepts in blockchain-enabled networks, (ii) we apply this framework to the Bitcoin network and recover its key properties, and (iii) we connect our modeling framework with powerful tools from control engineering, such as Lyapunov-like functions, to properly engineer economic systems with provable properties. Apart from the aforementioned contributions, the mathematical framework herein proposed lays a foundation for engineering more general economic systems built on emerging Turing complete networks, such as the Ethereum network, through which complex alternative economic models are explored.
Amaç: Kripto parabirimleri teknolojinin gelişmesiyle birlikte son yıllarda önem kazanmış ve dahaçok kullanılır hale gelmiştir. Merkezi bir otoriteye bağlı olmayan vekriptografik sistemler ile güvenliği sağlanan bu para birimlerinden en bilineniBitcoin’dir. Bu çalışmada, başlıca kripto para birimleri ve işleyiş süreçleriincelenmiştir. Buna ek olarak Bitcoin’in döviz, hisse senedi emtia piyasalarıve faiz ile olan ilişkisi ele alınmıştır. Yöntem: Çalışmadakullanılan veri setinin frekansı aylık olup Mart-2012 ile Mayıs-2018 döneminikapsamaktadır. Zaman serisi yöntemlerinden Johansen Eşbütünleşme ve GrangerNedensellik analizleri uygulanmıştır.Bulgular: Çalışmanınsonuçlarına göre, Bitcoin fiyatlarının artan bir trende ve yüksek birvolatiliteye sahip olduğu görülmektedir. Faiz değişkeni ile Bitcoin fiyatları arasında diğer analizler ve Grangernedensellik testi sonuçlarına göre istatistiksel olarak anlamlı bir ilişkivardır.
Este artigo elucida aspectos jurídicos e regulatórios do bitcoin (BTC) com objetivo de reduzir a insegurança jurídica em que se encontram as operações realizadas com a criptomoeda no Brasil. Essa pesquisa descritiva de cunho qualitativo e método dedutivo averigua, por meio do estudo da legislação e doutrinas pertinentes, a quais órgãos reguladores do Sistema Financeiro Nacional (SFN) as operações com o BTC estão submetidas. Para tanto, são introduzidas as funcionalidades, potencialidades e limitações do blockchain, tecnologia subjacente à criptomoeda. Após, são destacados aspectos relevantes do Sistema Financeiro Nacional. Em seguida, busca-se classificação conceitual jurídica adequada ao Bitcoin. Findas essas etapas, o trabalho sugere que, em razão da natureza jurídica do bitcoin como bem intangível, no atual aparato legal, não há previsão regulatória sobre o BTC, motivo pelo qual, no momento, operações com a moeda virtual não estão submetidas a qualquer órgão do SFN.
Nowadays many applications have employed the blockchain technology from sam- ple cryptocurrency to smart contracts applications. Bitcoin is one of the cryp- tocurrency application and digital payment system. It is considered as the first decentralized digital currency system. It was invented by unidentified person or group under the name of Satoshi Nakamoto in 2009 (Nakamoto, 2008). The most three features should be achieved by Bitcoin are decentralized, users anonymity, and consensus. In order to achieve these vital features the Bitcoin system should be provably secure against the attacks. Many attacks have been proposed to change unfairly the reward system of the mining pool and allow the malicious miners to earn undue wage. Selfish Attack, Block Withholding (BWH) Attack and Fork- ing After Withholding (FAW) Attack are three attacks which abusing the reward system and letting the infiltration miners to receive un unearned profits and as a sequence this will affect the decentralized feature of the Bitcoin system. Some studies proposed a solution for Selfish Attack and Block Withholding attack such (Eyal and Sirer, 2014b) and (Bag et al., 2017). FAW attack is first introduced by (Kwon et al., 2017) where this attack combines two attacks: Selfish and BWH attacks. In order to come up with a solution for FAW attack (Kwon et al., 2017) propose partial countermeasures for preventing their FAW attack. However, their solution is neither perfect nor practical. Therefore this study addresses this attack and analyzes its strategy then come up with a prevention solution. The result of this study shows that our prevention solution is practical and more effcient.
(eng) The main conceptual element this thesis orbits around is the idea of using social networks as a data source. First, classical trading theory and current usage of data obtained from social networks is reviewed. Taking all this information into account, a forecasting of the Bitcoin price is performed using both classical methods and machine learning Neural Networks. In order to obtain data from social networks, another complexity layer needs to be added by accessing the sources through APIs and directly web-scrapping the net. The results of all of this complex implementation are given with a strong focus on visualisation using several different techniques. Finally, after a critical discussion a Future Work chapter is introduced, where many possible follow-ups are drawn up.
Long Finance's Eternal Coin research programme has produced this report entitled “On-line Simulation For Cryptocurrencies: Risk Control Framework”.
Cryptocurrency development has been an exciting area for several years, with many new ideas coming forward and still the potential of a new launch that solves the biggest technical and commercial challenges. However, to date, almost all the 1,500+ cryptocurrencies that have been launched have died away, and even Bitcoin has serious technical limitations that have prevented it from being a competitive payment system in most situations. Cryptocurrencies have been seriously impacted by technical problems, disagreements, fraud, hacks, competition, regulation, lack of popularity, apathy, and sheer incompetence.
To increase the odds of success, those who aspire to a successful cryptocurrency need to think through the challenges they may face, make plans, make design choices, and develop capabilities that help them survive. They need control frameworks, practices, and procedures to create business value and minimize risk. While boring, intellectually these are tough and need to respond to the special characteristics of cryptocurrencies. This report looks at the control needs of cryptocurrencies mainly from the perspective of their creators and regulators (such as they are so far). The objective is to make recommendations on controls for cryptocurrencies that are not too prescriptive, but more helpful than generic control frameworks such as COSO’s frameworks for internal control and enterprise risk management (Committee of Sponsoring Organizations of the Treadway Commission 2013, 2017), and variations on them (e.g. Basel Committee on Banking Regulation 1998, Financial Reporting Council 2014).
This initial report complements previous Long Finance work on governance, audit, and standards for smart ledger systems. It also reflects the focus of the Eternal Coin research programme, a global discussion on the nature of money and the concept of value over the long term.”
This article intention was to set up the big picture of all 1,639 cryptocurrencies up and give a policy recommendation for Thai government. Hence, there were three following objectives as follows: 1) to investigate the state of the art of all cryptocurencies in the source of Code / Forking due to limitation of number of pages 2) to identify the best practice of cryptocurrency, and 3) to study the role of General Prayuth Chan-o-cha’s government towards cryptocurrency. Documentary research and descriptive statistics like frequency and percentage were used in this study. The findings found that there were twelve groups of qualified cryptocurrencies in CoinMarketCap, led by two well-known giant family of crypto market, Ethereum (35.5%) and Bitcoin (16.1%). Then, the best practices were on the provision of coins or tokens, twelve techniques for managing blokchain (such as Blockchainas-a Service), blocktime was between 0.03 and 30 minutes with Mean = 1.96, S.D. = 2.29 whereas TPS was between 0 - 1,400,000 with Mean = 1341.87 and S.D. = 36021.52, most of cryptocurrencies had their own Web Site (95.8%) and E-mail (78.8%), coding played a big role in cryptocurrency such as C . Last, cryptocurrency had both open and hidden-and-dark faces. In the open face, tax, law, people’s identification will be useful. In contrary to the open side, setting an autonomous public organization is one and only one solution for all cryptocentric affairs.
This study analyses the effect of adding bitcoin into the portfolio by exploiting the Long Only investment strategy. The Portfolio consists of five assets: bitcoin, crude oil price index, stock exchange of Thailand (SET) price index, the exchange rate between Thai and USD and Thai government bond compound with treasurer bill. The model used for modelling the return of all asset is Multivariate t-copula based on GARCH and also measure the risk of the portfolio using the Value-at-risk (VaR) under the condition of minimizing the variance of return. We find that when adding more bitcoin into the portfolio, the return and risk of asset increased. If we only invest in bitcoin, we will face the risk at 16.90% and gain 6.27%. When comparing the effectiveness of portfolio by using Return-risk ratio, it found that portfolio with bitcoin shows the higher return rate than portfolios without bitcoin. Therefore, it can conclude that bitcoin could indeed increase the effectiveness of portfolio.
The Internet of Things (IoT) is a name coined to the digital ecosystem of numerous internet connected devices. It brings the physical world closer to the digital one and as a result, allows for new applications and services. The emergence of Blockchain, a distributed ledger technology, presents a possible solution to ensure trust in decentralized systems. Blockchain brings trust, immutability, and verifiability of a distributed ledger in a decentralized network which could be useful to build trust in IoT. However, the integration of IoT with Blockchain involves a number of challenges. The use of Blockchain within the IoT is a recent and a fast paced topic. Therefore, conducting a systematic literature review is essential to understand what has been proposed on the topic. Recent work has provided a systematic review with a focus on Bitcoin. In this paper, we present a systematic review of more recent work on Blockchain and IoT, with a broader focus on Blockchain platforms beyond Bitcoin. Our work provides an overview of what has been done so far on the use of Blockchain and IoT.
Sara Rouhani, Luke Butterworth, Adam D. Simmons, Darryl G. Humphery · 5 authors
The set of distributed ledger architectures known as blockchain is best known for cryptocurrency applications such as Bitcoin and Ethereum. These permissionless block chains are showing the potential to be disruptive to the financial services industry. Their broader adoption is likely to be limited by the maximum block size, the cost of the Proof of Work consensus mechanism, and the increasing size of any given chain overwhelming most of the participating nodes. These factors have led to many cryptocurrency blockchains to become centralized in the nodes with enough computing power and storage to be a dominant miner and validator. Permissioned chains operate in trusted environments and can, therefore, avoid the computationally expensive consensus mechanisms. Permissioned chains are still susceptible to asset storage demands and non-standard user interfaces that will impede their adoption. This paper describes an approach to addressing these limitations: permissioned blockchain that uses off-chain storage of the data assets and this is accessed through a standard browser and mobile app. The implementation in the Hyperledger framework is described as is an example use of patient-centered health data management.
The rise of fraudulent cases seems to be a nuisance to an organization as they're an investment of money. Various resources also gives the impression to be on someone else, who has false claims. The verification process of these organizations are long and tedious process where the organization would have lost its time and resource on. Blockchain technology was introduced fairly recently in literature, which is the underlying technology behind the very popular cryptocurrency Bitcoin. The blockchain is a decentralized approach, it is secured by design network which was to overcome double spending problem by a central server. The concept of servers is eradicated in this architecture, where the data is distributed across geographically on separate ledgers. Blockchain applications have diversified as MIT Media Labs introduced Blockcerts for certification of academic records. Ethereum is platform for developing these decentralized applications using Blockchain ledgers. Ethereum uses a concept called Merkle trees which is the concept used for verification through hashing. As per the working in the literature; this application would make verification of academic documents simple and quick with the usage of Blockchain clients such as Ethereum and an IPFS hash. In this paper we propose a system that provides a solution that addresses the above mentioned issues.
Kripto parateknolojisi, insanların herhangi bir aracıya ihtiyaç duymadan dünyanın dört biryanında ödeme yapmalarını sağlar ve internet üzerinden çalışır. Bu teknolojininortaya çıkışı ile dikkatler bu paralara çevrilmiş, fiyatları hızla artmayabaşlamış ve aynı zamanda oynak hale gelmişlerdir. Bu çalışmada GARCH (1,1)modeli kullanılarak Bitcoin ve Litecoin piyasalarında haftanın günü ve yılınayı etkilerinin varlığı incelenmiştir. Çalışma dönemi 1 Mayıs 2013-21 Aralık2016 arasını kapsamaktadır. Elde edilen sonuçlar Bitcoin ve Litecoingetirilerinde haftanın günü ve yılın ayı etkilerinin var olduğunugöstermektedir. Pazartesi, Salı ve Cuma günlerinin Bitcoin getirileri üzerindepozitif ve anlamlı, Cumartesi’nin ise Litecoin getirileri üzerinde negatif veanlamlı etkisi olduğu tespit edilmiştir. Ayrıca, yılın ayı etkisi açısındanŞubat, Ekim ve Kasım aylarının Bitcoin üzerinde pozitif ve anlamlı, Litecoingetirilerinde ise Ağustos ayının negatif ve anlamlı etkisiolduğubelirlenmiştir.
We propose a decentralized routing algorithm that can be implemented in Bitcoin Lightning Network. All nodes in the network contribute equally to path searching. The algorithm is inspired from ant path searching algorithms.
Blockchain is one of the most popular topics for discussion now. However, most experts still see this technology as only part of Bitcoin, other crypto-currencies or money transfer systems. Often, new solutions, proposed by young researchers, are blocked by reviewers, only because these solutions can not be used for Bitcoins. However, Blockchain technology is more universal and can be used also in other areas, for example, in IoT, WSN and mobile devices. This paper considers the implementation of Blockchain technology in sensor networks as an element of IoT. The concept of "Rolling Blockchain" was proposed, which can be used to build WSN with the participation of Smart Cars, as nodes of the network. The order of block formation and structure in the chain is proposed and a mathematical model is created for it. We estimate the optimal number of WSN nodes, the number of connections between nodes, for specified network reliability values, was performed.
Muneer Maher A Al-shatir, Ahmed Sufyan Abdullah, Suhail Shareef
Cryptocurrency is considered a significant financial ground-breaking financial product which has led to a new revolution in financial market, affecting many countries and institutions globally, in both the economic and regulatory level. The huge impact of its existence can be seen by the enormous volume of borderless transactions, which occasionally overwhelming the economic size of some countries. The objective of this article is thus, to explore the reality of cryptocurrency focusing on Bitcoin as a case study. Besides, the article also aims to measure the efficiency of the currency technically and economically as to make assumptions on the probable impacts should it happen that the currency is adopted in main stream monetary system. Eventually, the article concludes that the adoption of the currency (bitcoin) may lead to inefficiency of the economy due to its nature of being overly exposed to the volatile market forces without any supervision. The adverse economic condition such as the risk of piracy and loss of rights, can also be expected as until currently there is no legal jurisdiction that guarantees the rights, apart of the presence of in the currency itself
Çalışmada gün geçtikçe popülerliği ve buna bağlı olarak toplam piyasa değerleri ve işlem hacimleri artan, çok sayıda ve çok çeşitli piyasalarda işlem gören kripto paraların fiyatlarının birbiri üzerindeki etkisi araştırılmıştır. Çalışmada, Bitcoin, Ethereum, Ripple, Bitcoin Cash, Cardano, Litecoin, NEM, NEO, Stellar ve IOTA kripto paralarının seçiminde toplam piyasa değerleri dikkate alınmıştır ve en yüksek toplam piyasa değerine sahip 10 kripto para analize dahil edilmiştir. 15 Aralık 2017 ve 17 Ocak 2018 tarihleri arasında çalışmaya konu olan kripto paraların günlük fiyat hareketleri arasındaki ilişkiyi incelemek için serilere Johansen Eşbütünleşme Testi ve Granger Nedensellik Testi uygulanmıştır. Çalışmanın sonucunda, Cardano’nun NEO’nun Granger nedeni olduğu, Bitcoin’in Bitcoin Cash’in Granger nedeni olduğu, Litecoin’in Bitcoin Cash’in Granger nedeni olduğu, NEM’in Bitcoin Cash’in Granger nedeni olduğu, Ripple’ın Bitcoin’in Granger nedeni olduğu, NEO ve Ethereum’un birbirinin Granger nedeni olduğu, NEO ve Litecoin’in birbirinin Granger nedeni olduğu ve NEM’in Stellar’ın Granger nedeni olduğu tespit edilerek, bu değişkenlerin fiyat hareketlerinin kısa dönemde birbirini etkilediği ortaya konmuştur.
Bitcoin mining is a process that serves to both verify sets of transactions and slowly introduce new currency into the system. As a reward for performing this process, miners are paid in bitcoin for the blocks they mine. It was originally thought that there was no incentive in trying to subvert the mining protocol—in other words, there was no reason to believe that miners could be profitable by somehow cheating the system. As it turns out, a specific strategy called “selfish mining” was discovered to increase profitability for miners under certain conditions. This paper presents the selfish mining strategy, traverses a revenue model associated with the strategy, and then simulates the bitcoin network to see how this revenue model holds up under complicated network conditions. Specifically, the selfish mining revenue model typically assumes there is one selfish miner in the network—I simulate the more realistic case of there being many selfish miners in the network. We find that the revenue model can overestimate selfish miner revenues by up to 100% and underestimate them by up to 300% depending on network variables such as the number of selfish miners, the power of those miners, and network latency (the speed of block propagation from one miner to another).
Die Preisvorhersage ist eine der größten Herausforderungen der quantitativen Finanzierung. Diese Thesis stellt ein Neuronales Netz-Framework vor, das eine tiefgreifende maschinelle Lernlösung für das Preisvorhersageproblem bietet. Das Framework wird in drei Zeitpunkten mit einem Multilayer Perzeptron (MLP), einem einfachen Recurrent Neural Network (RNN) und einem Long Short Term Memory (LSTM) realisiert, die lange Abhängigkeiten lernen können. Wir beschreiben die Theorie der neuronalen Netze und des Deep Learning, um eine reproduzierbare Methode für unsere Anwendungen auf dem Kryptowährungsmarkt zu erstellen. Da die Preisvorhersage verwendet wird, um finanzielle Entscheidungen wie Handelssignale zu treffen, vergleichen wir verschiedene Ansätze des Vorhersageproblems, indem wir überwachte Lernmethoden in Klassifikationsaufgaben untersuchen. Wir untersuchen diese Modelle, um Preisrichtungen von wichtitgen Kryptowährungen außerhalb der Stichprobe mit einer rolling window regression Methode vorherzusagen. Für dieses Ziel erstellen wir ein Klassifikationsproblem, das voraussagt, ob der Preis jeder Kryptowährung als Grundlage für dreimonatige Handelsstrategien erheblich zu- oder abnimmt. Wir bauen verschiedene Handelsstrategien auf, basierend auf Long- oder Long- / Short-Positionen, die auf unseren Prognosen aufbauen, und vergleichen ihre Performance mit einer passiven Index-Investition auf dem Cryptowährungsmarkt, die CRIX (Trimborn and Härdle, 2016) folgt. Cryptocurrencies, Bitcoins sind die bekanntesten, basieren auf elektronischem Geld auf Blockchain-Technologie, die als eine dezentrale Alternative zu Währungen verwendet werden kann. Dank ihrer zahlreichen Anwendungen hat der Markt für Kryptowährung im Jahr 2017 ein exponentielles Wachstum erfahren. Wir vergleichen verschiedene gewichtete Portfolios, um zu testen, wie ein Anleger von fundamentalen Indikatoren wie der Marktkapitalisierung profitieren kann. Wir finden, dass LST die beste Genauigkeit für die Vorhersage von Richtungsbewegungen für die wichtigsten Kryptowährungen von CRIX hat und dass ein gleich gewichtetes Portfolio CRIX in den ersten Quartalen 2017 schlägt.
Owing to Satoshi Nakamoto's brilliant idea, a P2P public ledger is shown to be implementable in anonymous network. Any Internet user can then join the anonymous network and contribute to the P2P public ledger by providing their computing power or proof-of-work. The proof-of-work is a clever implementation of one-CPU-one-vote by anonymous participants, and it protects the Bitcoin ledger from illegal modification. To compensate the nodes for their work, a cryptocurrency called Bitcoin is issued and given to nodes. However, the very nature of anonymity of the ledger and the cryptocurrency prevent the technology from being used in fiat money economy. Cryptocurrencies are not traceable even if they are used for money laundering or tax evasion, and the value of cryptocurrencies is not stable but fluctuates wildly. In this white paper, we introduce Gruut, a P2P ledger to implement a universal financial platform for fiat money. For this purpose, we introduce a new consensus algorithm called `proof-of-population,' which is one instance of `proof of public collaboration.' It can be used for multiple purposes; as a P2P ledger for banks, as a powerful tool for payment, including micropayment, and as a tool for any type of financial transactions. Even better, it distributes the profit obtained from transaction fee, currently dominated by a third party, to peers that cannot be centralized. Energy requirements of Gruut are so low that it is possible to run our software on a smartphone or on a personal computer without a graphic card.
Spyros Makridakis, Antonis Polemitis, George M. Giaglis, Soula Louca
Blockchain technologies, once used exclusively for buying and selling bitcoins, have entered the mainstream of computer applications, fundamentally changing the way Internet transactions can be implemented by ascertaining trust between unknown parties. In addition, they ensure immutability (once information is entered it cannot be modified) and enable disintermediation (as trust is assured, no third party is required to verify transactions). These advantages can produce disruptive changes when properly exploited, inspiring a large number of applications. These applications are forming the backbone of what can be called the Internet of Value, bound to bring as significant changes as those brought over the last 20 years by the traditional Internet. This chapter investigates blockchain and the technologies behind it and explains their technological might and outstanding potential, not only for transactions but also as distributed databases. It also discusses its future prospects and the disruptive changes it promises to bring, while also considering the challenges that would need to be overcome for its widespread adoption. Finally, the chapter considers combining blockchain with Artificial Intelligence (AI) and discusses the revolutionary changes that would result by rapidly advancing the AI field.