This, together with the related term Bitcoin, was a revolution in blockchain as envisioned by the mystery character Satoshi Nakamoto up to 2008. All this changes the very way the foundations of digital exchange and storage were thought about: decentralized, transparent, immutable, the very fundamentals of Distributed Ledger Technology enabling safe data exchange without an intermediary. The blockchain is fundamentally a chain of blocks carrying information about transactions, including times and cryptographic hashes, each of these connecting to the previous one in one unbroken chain, for which no modification is viable. The whole design of Blockchain has been to solve a number of issues, including double spending, fraud, and inefficient records, with distributed nodes and consensus mechanisms such as Proof of Work and Proof of Stake, facilitated by cryptographic keys. Other areas beyond cryptocurrency where quite a number of innovative uses are cut across include supply chain, healthcare, financial, and real estate sectors. For example, while the supply chain process is being promoted to become effective and transparent in order to ensure the origin and quality of the product, adding to the guarantee that the user's personal health information will not be accessed and tampered with, blockchain uses smart contracts in automating agreement processes within the contract. All of them are expecting cost reduction, operating efficiencies enhancement, enhanced securities of many industries. Anyhow, there exist quite a number of serious obstacles standing in the way of the wide application of blockchain technology. Firstly, the problem of scalability has still been an issue whereby the network performance tends to be problematic when users are increased. Besides, energy wasting cannot be ignored-apparently mostly a challenge from the PoW kind of system proved to be consuming too much energy, standing big on the road to sustainability. Of course, the mere lack of any kind of international rules and standards is already a complication in making them work. It also underlines failures in the adoption of the system or in decentralizing and is still an open technical and organizational challenge on how to combine blockchain with traditional structures. Their solutions require compounding ideas: sharding of blockchain to make it big, off-chain solutions for the blockchain to be many but thin, and provision of amicable solution consensus mechanisms for environmental conservation. Besides coherent policy vision, in addition to the existing cornerstones of regulation besides well-laid-out standards of interoperability, it is important to create confidence and give a road map across different industries. This paper hereby conceptually reviews the literature with respect to how the blockchain technology was designed to show revolutionary capability in the different fields and what keeps on tormenting it with its future.KEYS: Blockchain technology; Distributed Ledger; Decentralization; Cryptographic keys; Consensus mechanisms; Proof of Work; Proof of Stake; Smart contracts; Supply chain management; Data immutability; Transparency; Scalability; Energy consumption; Challenges to regulatory bodies; Security vulnerability; Sharding; off- chain processing; Interoperability; Applications using blockchain; Architecture of blockchain.
Blockchain has been widely adopted in the last few years even though it is in its infancy. The first well-known application built on blockchain technology was Bitcoin, which is a decentralized and distributed ledger to record crypto-currency transactions. All of the transactions in Bitcoin are anonymously transferred and validated by participants in the network. Bitcoin protocol and its operations are so reliable that technologists have been inspired to enhance blockchain technologies and deploy it outside of the crypto-currency world. The demand for private and non-crypto-currency solutions have surged among consortiums because of the security and fault tolerant features of blockchain. To introduce blockchain concepts, we survey the three most popular blockchain architectures: Bitcoin, Ethereum, and Hyperledger Fabric. We then build Gradubique, a blockchain network built on top of Hyperledger Fabric. Gradubique allows instructors from any school to post exam and course grades to the Gradubique network. Employers and graduate schools can extract transcripts from Gradubique. Security is guaranteed by the blockchain technology. Standardization and translation of transcripts can be built into the network, and the distributed nature of the network can make it virtually cost-free.
ENGLISH: \n \nBitcoin is one of digital currencies by cryptography as the basic system with the highest price in digital marketplace until 2018, so it becomes one of digital asset used to invest and becomes one of the most popular investment tools in society. But this phenomenon still become polemic because it has no explicit regulations yet. So, this research objectives are to know the mechanism of Bitcoin investment in society and the legal expert opinion towards it. \n \nThis research used empirical juridical method with sociological juridical approach. The analytical method is descriptive and concluded in inductive way that explained the result from specific to general. \n \nThis research results are the Bitcoin investment mechanism in society divided into mining and trading activity. In Islamic views, the legal expert opines that mining activity is allowed to do because there are two kinds of akad did in it and has no element of maysîr at all. Whereas, if does not be incompatible with sharia principal, Bitcoin trading is allowed to do. In positive law views, these two types of investment activity still had no explicit regulation yet. Although it can to be associated with some regulations such as Civil Code, The Currency Law, Electronic Information and Transaction Law, and Bank of Indonesia Regulation, it still need to regulate explicitly and written in specific role, either in regulation or fatwa forms, so it gives the legal certainty to society. Hopefully, this research provides the suggestion to government to law the vacuum of norm of Bitcoin. \n \nINDONESIA: \n \nBitcoin merupakan salah satu mata uang digital yang berbasis program kriptografi dengan harga tertinggi hingga tahun 2018 sehingga menjadi salah satu aset digital untuk berinvestasi dan menjadi salah satu sarana investasi paling popular di masyarakat. Namun, fenomena tersebut masih menjadi polemik karena tidak dinaungi oleh payung hukum yang jelas. Penelitian ini bertujuan untuk mengetahui mekanisme investasi Bitcoin yang dilakukan serta pandangan pakar hukum terhadap fenomena tersebut. \n \nPenelitian ini menggunakan metode yuridis empiris, dengan pendekatan yuridis sosiologis. Analisis yang digunakan bersifat deskriptif dan disimpulkan secara induktif yaitu dengan menguraikan kasus yang bersifat khusus dan disimpulkan secara umum. \n \n \nHasil penelitian yang diperoleh adalah mekanisme investasi Bitcoin yang dilakukan dapat berupa mining, dan trading. Dalam perspektif Islam, pakar hukum berpendapat bahwa aktivitas mining boleh untuk dilakukan karena terdapat dua akad yang berbeda selama melakukan prosesnya, dan tidak mengandung unsur maysîr. Sedangkan, trading Bitcoin boleh untuk dilakukan selama tidak bertentangan dengan prinsip syariah. Secara hukum positif, kedua aktivitas tersebut belum memiliki payung hukum yang jelas. Meskipun dapat dikaitkan dengan beberapa peraturan, seperti KUH Perdata, Undang-Undang Mata Uang, Undang-Undang ITE, serta Peraturan Bank Indonesia, investasi Bitcoin perlu untuk diatur secara tertulis dalam peraturan khusus yang berbeda, baik dalam bentuk peraturan perundang-undangan ataupun fatwa. Sehingga akan memberikan kepastian hukum terhadap masyarakat. Dengan adanya penelitian ini diharapkan dapat memberikan masukan pada pemerintah untuk menyikapi kekosongan hukum Bitcoin.
Bitcoin is a cryptocurrency and a decentralized semi-anonymous peer-to-peer payment system in which the transactions are verified by network nodes and recorded in a public massively replicated ledger called the blockchain. Bitcoin is currently considered as one of the most disruptive technologies. Bitcoin represents a paradox of opposing forces. On one hand, it is fundamentally social, allowing people to transact in a peer-to-peer manner to create and exchange value. On the other hand, Bitcoin's core design philosophy and user base contain strong anti-social elements and constraints, emphasizing anonymity, privacy, and subversion of traditional centralized financial systems. We believe that the success of Bitcoin, and the financial ecosystem built around it, will likely rely on achieving an optimal balance between these social and anti-social forces. To elucidate the role of these forces, we analyze the evolution of the entire Bitcoin transaction graph from its inception, and quantify the evolution of its key structural properties. We observe that despite its different nature, the Bitcoin transaction graph exhibits many universal dynamics typical of social networks. However, we also find that Bitcoin deviates in important ways due to anonymity-seeking behavioral patterns of its users. As a result, the network exhibits a two-orders-of-magnitude larger diameter, sparse treelike communities, and an overwhelming majority of transitional or intermediate accounts with incoming and outgoing edges but zero cumulative balances. These results illuminate the evolutionary dynamics of the most popular cryptocurrency, and provide us with initial understanding of social networks rooted in and driven by anti-social constraints.
Purwono Purwono, Alfian Ma’arif, Wahyu Rahmaniar, Qazi Mazhar ul Haq · 6 authors
Blockchain technology has a promising future in a number of industries and enterprises. Formerly connected to virtual currency like Bitcoin, blockchain has evolved into a versatile technology with many applications. In the upcoming years, it is predicted that blockchain will revolutionize a variety of industries, including banking, supply chain management, healthcare, voting systems, and more. The future of blockchain technology depends critically on its ability to increase security and transparency. By providing a decentralized and unchangeable record, eliminating the need for middlemen, and boosting participant confidence, blockchain promotes secure and traceable transactions. This transparency has the potential to transform whole industries by reducing fraud, streamlining processes, and increasing output. Blockchain also has the power to change financial systems. Blockchain-based smart contracts facilitate faster, more efficient transactions by automating and enforcing contractual agreements without the need for middlemen. By enabling speedier cross-border transactions, reducing costs, and boosting financial inclusion, tokenization and blockchain-based digital currencies have the potential to overturn conventional banking institutions. Blockchain’s key attributes, including decentralization, transparency, immutability, and security, make it a desirable choice for a range of organizations. Cross-border payments, trade finance, and smart contracts are just a few of the financial sector processes that blockchain technology has the potential to enhance and automate, lowering costs and increasing productivity. Additionally, the tamper-resistance of blockchain technology can boost transaction security and reliability, allowing for a wider use in traditional financial institutions. Outside of the financial industry, blockchain technology has a lot of promise, particularly in industries like supply chain management, healthcare, energy, intellectual property, and governance. By enabling transparent and traceable transactions, blockchain may improve supply chain efficiency, ensure product authenticity, and boost customer trust. By facilitating the secure exchange of patient data and research data, the decentralized nature of blockchain technology can enhance data security, interoperability, and privacy in the healthcare sector. A more decentralized and sustainable energy ecosystem may be supported by blockchain technology through peer-to-peer energy exchange, grid management, and monitoring of renewable energy certificates in the energy sector. Additionally, blockchain technology has the potential to transform decentralized governance structures, voting procedures, intellectual property rights, and digital identity management. By allowing people to own and manage their digital identities, blockchain can enhance privacy and reduce identity theft. Blockchain-based voting systems can offer transparency, security, and verifiability, thereby increasing voter turnout and public trust in democratic institutions. Blockchain can also enable the secure and transparent management of intellectual property rights, fostering author credit and just compensation.
Historically, the means of payment has evolved from time to time. The current phenomenon is Bitcoin, claimed by its users as a means of future payments, that have been the major attention of many people, from people in business to students. The research question in this study was how the existence of Bitcoin as a medium of exchange is, and how its existence as a medium of exchange is viewed based on the maqāṣid al-syar 'īyah. This used the literature research method and the maqāṣidī approach by applying the tarjih maslahat method. The existence of Bitcoin as a medium of exchange is considered valid because of the 'urf recognition. However, it requires a legal status from the government because it is related to al-maslahat al-mmāmmah, the mafsadat (damage) value of Bitcoin is higher than its maslahat (benefit) value. Hence, it is concluded that Bitcoin is valid as a medium of exchange. Still, its use must be limited due to the mafsadat (harm) probability that is more dominant at the ḍarūriyyāt (primary needs) level, following the principle of "rejecting the harm is prioritized than realizing the benefit."
 Abstrak: Berdasarkan sejarah, alat pembayaran dari masa ke masa telah mengalami evolusi, pada saat ini terdapat sebuah fenomena yaitu fenomena Bitcoin yang diklaim oleh para penggunanya sebagai alat pembayaran masa depan yang telah banyak menyita perhatian orang mulai dari kalangan pengusaha hingga mahasiswa. Bitcoin memiliki beberapa kelebihan jika dibandingkan dengan alat pembayaran yang biasa digunakan, di antaranya yaitu sifatnya yang desentralisasi sehingga tidak ada pengendali pusat yang akan ikut campur di dalamnya. Sedangkan pada kebiasaannya, alat pembayaran di suatu wilayah berada di bawah pengawasan pemerintah karena alat pembayaran tergolong kepada kebutuhan primer yang menyangkut kesejahteraan umum. Pertanyaan penelitian dalam skripsi ini adalah bagaimana eksistensi Bitcoin sebagai alat tukar dan bagaimana keberadaan Bitcoin sebagai alat tukar berdasarkan maqāṣid al-syar‘īyah. Dalam penelitian ini penulis menggunakan metode penelitian kepustakaan dan pendekatan maqāṣidī dengan menerapkan metode tarjih maslahat. Keberadaan Bitoin sebagai alat tukar dianggap sah karena terdapat pengakuan secara ‘urf. Akan tetapi status sah tersebut perlu mendapatkan pengesahan pemerintah karena terkait dengan al- maslahat al-‘āmmah, nilai mafsadat pada Bitcoin lebih dominan jika dibandingkan dengan nilai maslahatnya. Dari paparan di atas disimpulkan bahwa keberadaan Bitcoin sah sebagai alat tukar, namun penggunaannya merupakan sesuatu yang harus dibatasi karena probabilitas mafsadatnya lebih dominan yang berada pada tingkat ḍarūriyyāt.. Hal ini sesuai dengan kaidah “menolak mafsadat di dahulukan dari pada mewujudkan maslahat.”
 Keyword: Eksistensi, Bitcoin, Maqāṣid al-Syar‘īyah.
This paper intends to review the need of cryptocurrency on the European and International market. Why cryptocurrency is bad and good at the same time for the international financial market is one of the main issues of this paper. Where are Bitcoin, Ethereum, Ripple, Bitcoin Cash, Litecoin going to and why cryptocurrencies are necessary on today’s market. Although there is no sure thing on crypto, on the long term, the market keeps going up and there is much interest in this direction.
Blockchain technology has enjoyed a massive adoption in cryptocurrencies such as Bitcoin. Following the success, many people have started to explore the possibility of implementing blockchain technology in different fields. We propose smart stamp duty, a system which can revolutionize the way stamp duty is managed and paid. The smart stamp duty offers significant improvements on the convenience when paying stamp duty. At the same time, the blockchain technology also provides the auditability of the transaction data. Smart stamp duty enables the expansion of the existing electronic stamp duty application to retail level as well as allows the taxpayers to pay the stamp duty of their electronic documents. Our proposed system also enables the taxpayers to print their electronic documents without losing the paid electronic-based stamps.
De forma acadêmica e construtiva, sem pretender esgotar o assunto, o presente artigo tem como objetivo realizar um estudo jurídico e econômico do bitcoin, que é a espécie de moeda virtual mais utilizada no mundo, mediante as ferramentas metodológicas da Análise Econômica do Direito, demonstrando como o uso de bitcoins nas transações realizadas pela sociedade empresária em recuperação pode reduzir os custos de transação e contribuir para uma recuperação judicial menos custosa, mais célere e mais eficiente, colaborando, ainda, para que a recuperação judicial cumpra os seus objetivos previstos no art. 47 da Lei n. 11.101/05, quais sejam, viabilizar a superação da situação de crise econômico-financeira do devedor, a manutenção da fonte produtora, bem como do emprego dos trabalhadores e dos interesses dos credores, promovendo, assim, a preservação da empresa e da sociedade empresária, sua função social e o estímulo à atividade econômica.Palavras-chave: Bitcoins. Análise Econômica do Direito. Custos de transação. Abstract In an academic and constructive way, without intending to exhaust the subject, this research aims to carry out a legal and economic study of bitcoin, which is the most used virtual currency in the world, through the methodological tools of Economic Analysis of Law , demonstrating how the use of bitcoins in transactions carried out by the recovering company can reduce transaction costs and contribute to a less costly, faster and more efficient judicial recovery, also helping to ensure judicial recovery meets its objectives Art. 47 of Law no. 11.101 / 05, which is to make it possible to overcome the economic and financial crisis of the debtor, the maintenance of the source, as well as the employment of workers and the interests of creditors, thus promoting the preservation of the company, its social function and stimulating economic activity. Keywords: Bitcoins. Economic Analysis of Law. Transaction costs.
We develop a uniform test for detecting and dating explosive behavior of a strictly stationary GARCH$(r,s)$ (generalized autoregressive conditional heteroskedasticity) process. Namely, we test the null hypothesis of a globally stable GARCH process with constant parameters against an alternative where there is an 'abnormal' period with changed parameter values. During this period, the change may lead to an explosive behavior of the volatility process. It is assumed that both the magnitude and the timing of the breaks are unknown. We develop a double supreme test for the existence of a break, and then provide an algorithm to identify the period of change. Our theoretical results hold under mild moment assumptions on the innovations of the GARCH process. Technically, the existing properties for the QMLE in the GARCH model need to be reinvestigated to hold uniformly over all possible periods of change. The key results involve a uniform weak Bahadur representation for the estimated parameters, which leads to weak convergence of the test statistic to the supreme of a Gaussian Process. In simulations we show that the test has good size and power for reasonably large time series lengths. We apply the test to Apple asset returns and Bitcoin returns.
With the more and more extensive application of blockchain, blockchain security has been widely concerned by the society and deeply studied by scholars. Moreover, the security of blockchain data directly affects the security of various applications of blockchain. In this survey, we perform a comprehensive classification and summary of the security of blockchain data. First, we present classification of blockchain data attacks. Subsequently, we present the attacks and defenses of blockchain data in terms of privacy, availability, integrity and controllability. Data privacy attacks present data leakage or data obtained by attackers through analysis. Data availability attacks present abnormal or incorrect access to blockchain data. Data integrity attacks present blockchain data being tampered. Data controllability attacks present blockchain data accidentally manipulated by smart contract vulnerability. Finally, we present several important open research directions to identify follow-up studies in this area.
Open access
2 source records
Blockchain Technology Applications and Security
Advanced Steganography and Watermarking Techniques
Bitcoin relies on a peer-to-peer overlay network to broadcast transactions and blocks. From the viewpoint of network measurement, we would like to observe this topology so we can characterize its performance, fairness and robustness. However, this is difficult because Bitcoin is deliberately designed to hide its topology from onlookers. Knowledge of the topology is not in itself a vulnerability, although it could conceivably help an attacker performing targeted eclipse attacks or to deanonymize transaction senders. In this paper we present TxProbe, a novel technique for reconstructing the Bitcoin network topology. TxProbe makes use of peculiarities in how Bitcoin processes out of order, or "orphaned" transactions. We conducted experiments on Bitcoin testnet that suggest our technique reconstructs topology with precision and recall surpassing 90%. We also used TxProbe to take a snapshot of the Bitcoin testnet in just a few hours. TxProbe may be useful for future measurement campaigns of Bitcoin or other cryptocurrency networks.
Abstract A blockchain replaces central counterparties with time-consuming consensus protocols to record the transfer of ownership. This settlement latency slows cross-exchange trading, exposing arbitrageurs to price risk. Off-chain settlement, instead, exposes arbitrageurs to costly default risk. We show with Bitcoin network and order book data that cross-exchange price differences coincide with periods of high settlement latency, asset flows chase arbitrage opportunities, and price differences across exchanges with low default risk are smaller. Blockchain-based trading thus faces a dilemma: Reliable consensus protocols require time-consuming settlement latency, leading to arbitrage limits. Circumventing such arbitrage costs is possible only by reinstalling trusted intermediation, which mitigates default risk.
Rômulo Rhemo Palitot Braga, Arthur Augusto Barbosa Luna
This article analyzes some of the existing digital anonymity technologies, as well as their impact on the process and facilitation of the money laundering process. It presents the concept of superficial Internet and clarifies the difference between the Deep Web and the Dark Web, exposing how it works one of its most important operating structures, the TOR protocol. It also details the operation of BitCoin, one of the most important crypto-coins today, and draws a parallel on how these technologies can impact the practice of money laundering, as well as discusses the capacity of the mechanisms currently in place to curb and punish it. The anonymity guaranteed by the use of BitCoin is so much that in the first half of May 2017, hackers infected thousands of computers in dozens of countries, including Brazil, the United Kingdom, the United States, China, Russia, Spain and Italy, encrypting computer files and requiring redemption payment for the coded data.
Azim Muhammad Fahmi, Noor Azah Samsudin, Aida Mustapha, Nazim Razali · 5 authors
In 2017, a significant number of individuals profited from the staggering growth of the price of Bitcoin from $800 USD in January to almost $20,000 USD in December. Because the cryptocurrency market being relatively new when compared to traditional markets such as stocks, foreign exchange, and gold, there is a significant lack of studies in regard to predicting its price behavior. This research is interested in evaluating a number of regression-based algorithms in predicting the price of the Bitcoin (BTC) against United States Dollar (USD). Among the algorithms that will be investigated include the Linear Regression (LR), Neural Network Regression (NNR), Bayesian Linear Regression (BLR), and Boosted Decision Tree Regression (BDTR). By applying such regression-based analysis algorithms, the findings f should further help document the behavior of such a brand new, challenging yet extremely lucrative market. Â
This The virtual currency is a paramount in a strong economical situation of any country in the future, especially the countries that try to lead the world with its economy, this currency has been created to replace the traditional currency of the countries that can be issued by any central bank and put a value for it, but the virtual currency is a currency that no one can control and manipulate its value and no one can use it to control any country economical situation (c.f. Selgin, 1988).The virtual currency helps poor countries to develop its economy because it will have the same currency that any developed country has with the same value. But the virtual currency will face a lot of problems before entering to market(Gandal, N., &Halaburda, H. (2014) and will face a lot of barriers that will stop the development of the state economy, some of those problems are: the culture of the country and the government laws and policies, plus there is an important problem that it will face and it represent by the economic agreements and the Unified Banks Network (e.g. Jerin, 2014).To solve those problems the research will use the qualitative method with an interpretive research philosophy, that helps the research to use specific case study that have similar situation to collect the second data and use the interview to collect the primary data.The interview that is made with experts will show some solution that answer the research question and it can be applied and the step to apply it to receive to needed solution to let the virtual currency be accepted in the market (Gandal, N., &Halaburda, H. (2014). Therefore, the government started to encourage the citizen and the companies to use this new currency, and they created an environment that helps those users to trust and accept it.This currency will face a lot of obstacles and problems at the beginning, the government will try to put plans and long term strategies to solve these problems before they occur, starting from creating and issuing new laws and policies arriving to create a large and strong educational advertising to let the citizen know this new currency and its benefits.Also, the private sectorsare responsible too, especially the bank sectors because they have the principle relation with this field and they have to motivate their customers to use it (Gans, J., &Halaburda, 2013).From this research, we will try to find some solutions that the concerned sector need to apply to let the virtual currency enter the market and let the citizen trust it and start trading with it (Gandal, N., &Halaburda, H. (2014).
Bitcoin is a cryptocurrency that is gaining popularity over the years. It can generate a significant amount of return while having a high volatility. Given the high risk, high return nature of Bitcoin, the study aimed at determining whether Bitcoin offers diversification benefit in a portfolio. Two characteristics of Bitcoin (correlation and volatility) were examined, and optimal portfolio analysis was conducted using different weights of Bitcoin. The study showed that Bitcoin's low correlations with most securities and assets in the market help diversify portfolios, but the currency's high volatility indicates that only a small amount of Bitcoin should be included in portfolio diversification.
À la fin de l’année 2017, le cours du Bitcoin a frôlé la barre symbolique des 20 000 dollars américains,créant ainsi un intérêt grandissant de la part des milieux d’affaires, des médias, des preneurs de décision, et du grandpublic. La communauté scientifique n’est pas en reste puisque des courants de recherche entiers sur le sujet sontapparus dans des disciplines aussi variées que la finance, l’économie, le marketing, l’éthique, l’informatique ou encorele droit. L’intérêt du duo cryptomonnaies – chaîne de blocs, en général, et du Bitcoin, en particulier –, s’est toutefoislimité à l’examen des aspects techniques, des capacités transactionnelles et des implications pour le commerce et lafinance. Très peu d’études se sont penchées sur l’examen des conséquences de ces systèmes d’échange décentraliséset pair-à-pair, tels que le Bitcoin et la chaîne de blocs, sur les configurations actuelles de la gouvernance mondiale.Cet article a pour objectif de faire un compte rendu commenté de l’ouvrage collectif Bitcoin and Beyond : Cryptocurrencies,Blockchains, and Global Governance. Dans cet ouvrage, Malcolm Campbell-Verduyn met à contribution plusieursauteurs afin de mettre en lumière la manière dont la chaîne de blocs déborde du strict cadre économique et financierpour s’intégrer dans la gestion des sphères politique, légale et juridique. Ce faisant, l’ouvrage lève le voile sur denombreuses implications des cryptomonnaies et de la chaîne de blocs pour la gouvernance mondiale, souventméconnues et très peu étudiées dans la littérature, mais d’importance capitale dans un monde de plus en plusmondialisé.
Abstract As world economy evolved over years, barter which is a primitive transaction system left its place to money system. Commodity and bimetallic systems of money resolved the problems, especially the requirement of double coincidence of wants and eased the trade within parties. Chronologically, paper system of money followed the commodity system and implemented via two methods. In the first method, convertible paper money is converted into gold and silver by the authority that issued paper money. In the second method that is still valid today, fiat money is accepted by parties because of its being a legal tender. Money supply definitions keep changing as new liquid assets emerge day by day. Especially after the post global financial crisis, central banks have a more critical function for the world economies. Keeping all these developments aside, surrounded by fintech trends, financial system has confronted with a new instrument bitcoin that is first introduced in 2009. Though there are still too many consideration about this new financial instrument, number of bitcoins has growing since 2009 and has reached almost 17 million as of September 2018. Some economists consider bitcoin and other cryptocurrencies as a threat especially for central banks’ emission power. In this study we try to shed light to bitcoin, other cryptocurrencies and blockchain technology with regard to their evolvement and whether they pose a threat or provide an opportunity to the financial system.
Smart Grids is an emerging technology promising significant changes in the economy and the social sphere. One among many challenges in their development and distribution is security. Considering recent hackers attacks on energy grids and taking into account the distributed structure of these systems the use of traditional means of computer protection and the search for a crime figure becomes more difficult or impossible. In this article, we introduce some application areas of smart grid forensic science, discuss the opportunities, and outline the open issues in the topic. We summarized challenges for forensic in Smart Grids in connection with a Blockchain and proposed a decentralized transaction platform based on Blockchain tailored to the energy sector with all the latest technology such as advanced metering infrastructure, distributed generation, etc.
This study investigates the asymmetric causal relations between Bitcoin and gold, Brent oil, US dollar, S&P 500 and BIST 100 Indexes for the weekly data of the period between November 2013 and July 2018 via by Hatemi-J (2012) test. The results indicate only a causal link going from the Bitcoin price to S&P 500 Index. Consequently, a change in Bitcoin prices appears to influence the investors’ decisions on the S&P 500 Index. Therefore, it can be said that the investors in S&P 500 Index have closely followed the new macro-financial developments in the market and have been active on the S&P 500 market. However, the presence of a causality relation between Bitcoin price and other variables cannot be determined. Thus, it is supposed that Bitcoin may exist in association with the commodity market and other global indicators in the future, along with the recognition of the Bitcoin currency by countries, its being accepted as a means of exchange and its increased reliability.