In his talk, Bela Gipp, Professor for Data & Knowledge Engineering at the University of Wuppertal, presented the blockchain-based trusted timestamping service Origin-Stamp. Bela developed OriginStamp as a Ph.D. student in 2012, as no convenient and tamper-proof method existed to create timestamps. Since then, OriginStamp has been used over 6 million times by researchers, journalists in war regions, pharmaceutical companies, and individuals. Use cases are the timestamping of ideas for patent applications, timestamping of digital archives or timestamping of pre-existing damage, e.g., when hiring a rental car. The service can be used via a website, mobile phone apps, or an API, which allows developers to easily make use of trusted timestamping in their own applications. Trusted timestamping is the process of securely tracing the creation and modification time of any digital file. In contrast to conventional commercial timestamping authorities, OriginStamp uses the blockchain of the cryptocurrency Bitcoin as a decentralized, tamper-proof, and cost-efficient timestamping authority. To try it yourself, visit www.originstamp.org.
Purpose The purpose of this paper is to explore the possible contributions of blockchain technology to creating new governance structures that facilitate social cooperation. Design/methodology/approach Conceptual analysis with key ideas in new institutional economics and political theory is used in this paper. Findings Blockchain technology provides a new tool through which political entrepreneurs can credibly alienate some of their power within a system of rules that they have established. Originality/value This paper links discussion of blockchain entrepreneurship in commercial markets to research into private governance.
High voter turnout in elections and referendums is very desirable in order to\nensure a robust democracy. Secure electronic voting is a vision for the future\nof elections and referendums. Such a system can counteract factors that hinder\nstrong voter turnout such as the requirement of physical presence during\nlimited hours at polling stations. However, this vision brings transparency and\nconfidentiality requirements that render the design of such solutions\nchallenging. Specifically, the counting must be implemented in a reproducible\nway and the ballots of individual voters must remain concealed. In this paper,\nwe propose and evaluate a referendum protocol that ensures transparency,\nconfidentiality, and integrity, in trustless networks. The protocol is built by\ncombining Secure Multi-Party Computation (SMPC) and Distributed Ledger or\nBlockchain technology. The persistence and immutability of the protocol\ncommunication allows verifiability of the referendum outcome on the client\nside. Voters therefore do not need to trust in third parties. We provide a\nformal description and conduct a thorough security evaluation of our proposal.\n
The Industrial Revolution 4.0 has changed the human perspective in interacting and doing business fundamentally. Business systems that are transformed into online systems have an impact on the way humans conduct financial transactions. Principles contained in Industry 4.0. provide an illustration that interconnection with the internet and good data security will result in the provision of fast information to produce decisions. The study uses a literature study approach that examines data and information from journals, textbooks, and he internet to conduct a deeper study of the application of industry principles 4.0 to financial transactions and accounting. based on the results of the study concluded that the financing transaction media had developed into the Fintech industry and the transaction system in the form of a payment gateway. The large number of financial transactions with the payment gateway system requires companies to do IT Spending intangible asset in the form of Big Data and Cloud Computing security systems. The technology provides benefits for the company in terms of data analysis and provision of information to speed up the decision making process and secure storage systems and affordable costs. Through the information technology media, it will facilitate management to make decentralized decision making.
Blockchain technology is the process of development of bitcoin, the blockchain technology as a distributed ledger of cryptocurrency transactions for digitized, decentralized, trusted and secured manner. The mainstream of blockchain technology is bitcoin, bitcoin concept made with ledger of every single transaction, transactions allows for hashing mechanism to verify the large amounts of data. Big data task requires that large amount of computational space, to generate the terabytes of data for ensuring the successful data processing techniques. The major impact on big data analytics requires more number of data and generated data can be depending upon different sectors from different organizations. This paper presents a state of definition, characteristics, transaction process, and applications, along with discussion of big data analytics are introduced. In blockchain technology covers the flaws of big data in fruitful relationship, with the factors of security, transparency, decentralization and flexibility, so that data to be analyze in different and efficient way for organizations all sizes in data analytics form.
Alexander Hentschel, Dieter Shirley, Layne Lafrance, Maor Zamski
Throughput limitations of existing blockchain architectures are well documented and are one of the most significant hurdles for their wide-spread adoption. In our previous proof-of-concept work, we have shown that separating computation from consensus can provide a significant throughput increase without compromising security. In our architecture, Consensus Nodes only define the transaction order but do not execute transactions. Instead, computing the block result is delegated to compute-optimized Execution Nodes, and dedicated Verification Nodes check the computation result. During normal operation, Consensus Nodes do not inspect the computation but oversee that participating nodes execute their tasks with due diligence and adjudicate potential result challenges. While the architecture can significantly increase throughput, Verification Nodes still have to duplicate the computation fully. In this paper, we refine the architecture such that result verification is distributed and parallelized across many Verification Nodes. The full architecture significantly increases throughput and delegates the computation work to the specialized Execution Nodes and the onus of checking it to a variety of less powerful Verification Nodes. We provide a full protocol specification of the verification process, including challenges to faulty computation results and the resulting adjudication process. Furthermore, we formally prove liveness and safety of the system.
Alexander Hentschel, Dieter Shirley, Layne Lafrance
Throughput limitations of existing blockchain architectures are one of the most significant hurdles for their wide-spread adoption. Attempts to address this challenge include layer-2 solutions, such as Bitcoin's Lightning or Ethereum's Plasma network, that move work off the main chain. Another prominent technique is sharding, i.e., breaking the network into many interconnected networks. However, these scaling approaches significantly increase the complexity of the programming model by breaking ACID guarantees increasing the cost and time for application development. In this paper, we describe a novel approach where we split the work traditionally assigned to cryptocurrency miners into two different node roles. Specifically, the selection and ordering of transactions are performed independently from their execution. The focus of this paper is to formalize the split of consensus and computation, and prove that this approach increases throughput without compromising security. In contrast to most existing proposals, our approach achieves scaling via separation of concerns, i.e., better utilization of network resources, rather than sharding. This approach allows established programming paradigms for smart contracts (which generally assume transactional atomicity) to persist without introducing additional complexity. We present simulations on a proof-of-concept network of 32 globally distributed nodes. While the consensus algorithm was identical in all simulations (a 2-step-commit protocol with rotating block proposer), block computation was either included in a consensus nodes' regular operations (conventional architecture) or delegated to specialized execution nodes (separation of concerns). Separation of concerns enables our system to achieve a throughput increase by a factor of 56 compared to conventional architectures without loss of safety or decentralization.
One of the more notable developments in financial infrastructure framework during recent years has been the emergence of networking alternative financing platforms, aimed at bringing together firms and individuals looking for capital and others that have money to lend, invest or donate. That was upticked by establishment of innovative financing platforms and different business models, starting with peer-to-peer lending and equity crowdfunding and evolving to cryptocurrencies and virtual services providers. The emergence of crypto-assets is an important area of interest for regulatory authorities, including those dealing with issuance and secondary trading of crypto-assets. This article focuses on the innovative financial technologies impact phenomena, acknowledging FinTech imputed substantial benefits to the financial sector infrastructure, as well as considerable risks. Along with the analysis of theoretical developments of domestic and foreign scholars, an attention is paid to global discourse involving G20 and G7 countries, Financial Stability Board, Financial Action Task Force on Money Laundering (FATF), The International Organization of Securities Commissions (IOSCO) that raise serious regulatory and systemic concerns, as well as wider policy issues, which both need to be addressed before such projects can be implemented in full scope and integration prospects. Thus, emphasized the necessity to introduce the highest standards of financial regulation, especially with regards to anti-money laundering and counteraction to financing terrorism (AML/CFT), anti-corruption, financial transparency, accountability and inclusion in order to guarantee the stability of the financial system and consumer protection with awareness towards possible regulatory gaps. Addressing a consideration of modern developments of virtual assets regulation framework abovementio ned issues are investigated inter alia with regard to aspects of sustainable development and coordination in measures of institutional economy and Financial Law. REFERENCES Hasanov S.S. Strukturni transformatsii ekonomiky i derzhavni finansy: problemy metodolohii, teorii, ekonomichnoi polityky. Kyiv: DNNU "Akad. fin. upravlinnia", 2012. 352 p. [in Ukrainian]. Bilorus O.H. Strukturna transformatsiia hlobalnoho kapitalu ta hiperfinansializatsiia vidtvoriuvalnykh protsesiv. Finansy Ukrainy. 2016. No. 1. P. 7-19 [in Ukrainian]. Kotliarevskyy Ya.V., Kolosova V.P., Maksymenko L.P. Rozvytok zbalansovanoho rehuliuvannia u sferi innovatsiinykh finansovykh tekhnolohii dyhitalizatsii zahalnoi miry vartosti. Biznes Inform. 2017. No. 11. P. 402-417 [in Ukrainian]. Douglass C. North. Institutions, Institutional Change and Economic Performance. Washington University, St Louis, 1991. 164 p. 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A digital currency in which encryption techniques are used to regulate the generation of units of currency and verify the transfer of funds, operating independently of a central bank. Therefore, Bitcoin is a form of digital currency that was designed by Satoshi Nakamoto (an unknown author of Bitcoin white paper 2008) and since then it has able to generate a considerable attention from investors due to its decentralized characteristics and the technology (block-chain) behind it. Bitcoin is a form of digital peer-to-peer currency system where transactions take place without a central bank. The transactions are verified by the nodes of the network and recorded in the Blockchain. Since the popularization of Bitcoin, this technology has caught attention of several technology companies who started to do research on the applications and opportunities of this technology. In this paper, an attempt has been made to capture the time varying variance of most prominent Cryptocurrency Bitcoin with world’s top traded currencies such as USD, GBP, Euro, Yen and CHF. In order to realise the stated objectives the researchers have collected the data from Prowess and Yahoo finance database from September 2013 till March 2018. In the first phase the collected data has been for normality and stationarity. Bitcoin was modelled for GARCH and EGARCH tests to capture the time varying volatility and leverage effect. Later the Johansen cointegration test has been conducted to find out the existence of cointegration between the top global currencies with Bitcoin. In the last phase the VECM has been run to capture the both long run and short relationship between Bitcoin and top five traded currencies. In the last phase Variance Decomposition has been run to capture the variance explained by the prominent global currencies on Bitcoin. Both USD and GBP share long run relationship with Bitcoin. Finally, the results have been compared with the possible evidence.
Machine learning and blockchain are two of the most notable technologies of recent years. The first is the foundation of artificial intelligence and big data analysis, and the second has significantly disrupted the financial industry. Both technologies are data‐driven, and thus there are rapidly growing interests in integrating both for more secure and efficient data sharing and analysis. In this article, we review existing research on combining machine learning and blockchain technologies and demonstrate that they can collaborate efficiently and effectively. In the end, we point out some future directions and expect more research on deeper integration of these two promising technologies.
Kriptovalute su novi oblik digitalnog novca koji funkcionira i nastaje na temelju složenih kriptografskih algoritama na računalnim mrežama. Ethereum je open-source program, zasnovan na blockchain tehnologiji, koja dozvoljava drugim programerima da grade i razvijaju decentralizirane aplikacije. Diplomski rad podijeljen je u tri glavna dijela. U prvom dijelu objašnjeni su osnovni pojmovi kako bi se razumjelo što su kriptovalute. U drugom dijelu rada objašnjeno je što je Ethereum, a u trećem dijelu opisani su osnovni principi rada i dijelovi koda Ethereum algoritma i programiranje u solidity programskom jeziku.
Xin Sun, Mirek Sopek, Quanlong Wang, Piotr Kulicki
While Blockchain technology is universally considered as a significant technology for the near future, some of its pillars are under a threat of another thriving technology, Quantum Computing. In this paper, we propose important safeguard measures against this threat by developing a framework of a quantum-secured, permissioned blockchain called Logicontract (LC). LC adopts a digital signature scheme based on Quantum Key Distribution (QKD) mechanisms and a vote-based consensus algorithm to achieve consensus on the blockchain. The main contribution of this paper is in the development of: (1) unconditionally secure signature scheme for LC which makes it immune to the attack of quantum computers; (2) scalable consensus protocol used by LC; (3) logic-based scripting language for the creation of smart contracts on LC; (4) quantum-resistant lottery protocol which illustrates the power and usage of LC.
In this paper, an application of three GARCH-type models (sGARCH, iGARCH, and tGARCH) with Student t-distribution, Generalized Error distribution (GED), and Normal Inverse Gaussian (NIG) distribution are examined. The new development allows for the modeling of volatility clustering effects, the leptokurtic and the skewed distributions in the return series of Bitcoin. Comparative to the two distributions, the normal inverse Gaussian distribution captured adequately the fat tails and skewness in all the GARCH type models. The tGARCH model was the best model as it described the asymmetric occurrence of shocks in the Bitcoin market. That is, the response of investors to the same amount of good and bad news are distinct. From the empirical results, it can be concluded that tGARCH-NIG was the best model to estimate the volatility in the return series of Bitcoin. Generally, it would be optimal to use the NIG distribution in GARCH type models since time series of most cryptocurrency are leptokurtic.
Cryptocurrencies have become a hot topic in finance: its price swings have gathered attention from investors therefore they have become an appealing asset to hold alongside other financial instruments. Despite this, do cryptocurrencies reflect the same investment behavior as seen in other assets? This paper aims to study irrational behavior with a focus on the disposition effect in stocks and Bitcoin. Is there a disposition effect in cryptocurrencies and, if so, how different are the effects between the two assets? The findings suggest there is disposition effect in Bitcoin, but it is stronger for stocks.
Ayman Alkhalifah, Alex Ng, A. S. M. Kayes, Jabed Chowdhury · 6 authors
Blockchain technology has become one of the most popular technologies for maintaining digital transactions. From the foundation of Bitcoin to the now-predominant smart contract, blockchain technology promises to induce a shift in thought-about digital transactions in many fields, such as energy, healthcare, Internet of Things, cybersecurity, financial services, and the supply chain. Despite blockchain technology offering many cryptography advantages such as immutability, digital signature, and hashing, it has suffered from several critical cybersecurity threats and vulnerabilities. In this chapter, we build upon the previous studies on vulnerabilities and investigate over 60 real cybersecurity incidents that have been happening on the blockchain networks between 2009 and 2019. We categorize those incidents against the key cybersecurity vulnerabilities in blockchain technologies and have developed a taxonomy that captures five types of cybersecurity threats and vulnerabilities based on five main players in blockchain. The outcome of this research prompted concerns and research direction in developing countermeasures to alleviate these risks. Blockchain; Cybersecurity; Attack; Threat; Vulnerability; Taxonomy.
Yoon-Chow Yeong, Khairul Shafee Kalid, Savita K. Sugathan
Dated back in 2008, the first blockchain-powered cryptocurrency-Bitcoin was introduced by Satoshi Nakamoto. Over the years, the types of cryptocurrencies available in the market amounted to more than 2,000. With the disruptive potential to revolutionize the traditional financial services, cryptocurrencies become a topic of interest among scholars, global regulators, investors, business operators, information technology enthusiasts and consumers. Nevertheless, the negative activities associated with cryptocurrencies such as money laundering and illicit trading, have resulted in the legality of cryptocurrencies remain controversial in the global context.As the worldwide regulators expressed different stance towards cryptocurrency acceptance and adoption, this study sought to gauge the individual’s behavioral intention to use cryptocurrency. Recognizing the dearth of study in Asian countries, especially the developing country, this study addresses the literature gap by focusing the case of Malaysian individuals. Specifically, this study investigated the effects of age, education level and income level differences in an individual’s behavioral intention to use cryptocurrency.The sample is made up of 176 Malaysian individuals who are equipped with cryptocurrency knowledge. The empirical data were gathered using online survey questionnaire via Google form. Subsequently, the data were analyzed using one-way analysis of variance (ANOVA) to understand the demographics effect on the intention to adopt cryptocurrency.Finally, the results revealed that the role of age, education and income level are not significant in influencing an individual’s behavior towards cryptocurrency adoption.
Hasil studi yang dilakukan oleh IlmuOne Data menyatakan bahwa e-commerce platform di Indonesia mengalami rata-rata pertumbuhan sekitar 100 persen dan kenaikan tertinggi yaitu 135 persen pada periode Januari sampai dengan Juni 2017. Salah satu contoh potensi penerapan smart contract adalah dalam bisnis jual beli dalam e-commerce, mengingat teknologi blockchain kini berkembang pesat tidak hanya pada cryptocurrency, tetapi juga dalam layanan keuangan dan pembayaran dengan smart contract. Namun, belum ditemukan pengaturan mengenai smart contract dalam hukum kontrak dan hukum jual-beli di Indonesia. Kemudian, perlindungan hukum para pihak dalam smart contract perlu untuk ditelusuri guna mewujudkan keadilan dan kepastian hukum dalam berkontrak. Dalam rangka menjawab permasalahan tersebut, peneliti menggunakan tipe penelitian normatif dengan pendekatan perundang-undangan dan pendekatan konseptual. Dalam penelitian ini, peneliti menghubungkan karakteristik smart contract dengan peraturan perundang-undangan mengenai kontrak, informasi dan transaksi elektronik di Indonesia. Peneliti juga menelusuri peraturan perundang-undangan mengenai perlindungan konsumen, serta asas-asas hukum kontrak yang dapat diterapkan untuk mewujudkan keadilan dan kepastian hukum para pihak smart contract. Dari penelitian ini, dapat disimpulkan bahwa smart contract merupakan bentuk kontrak yang sah dan dapat diterapkan di Indonesia dengan adanya peraturan mengenai kontrak, khususnya kontrak elektronik. Kemudian, penerapan Asas Proporsionalitas dan Asas Itikad Baik dapat mewujudkan smart contract yang berkeadilan dan menguntungkan para pihak.
Spanish abstract: En la presente investigacion, se aborda la Organizaciones Autonomas Descentralizadas, desde un aspecto de representacion, funcion ejecutiva y actos de administracion en los gobiernos contemporaneos. Se realiza un estudio sobre la tecnologia Blockchain en armonia con las circunstancias de participacion social actual, concluyendo en un contrato social tecnologico como espina dorsal de la era de la informacion y comunicacion.
English abstract: In this research, Decentralized Autonomous Organizations are approached, from an aspect of representation, executive function and acts of administration in contemporary governments. A study is carried out on Blockchain technology in harmony with the current social participation circumstances, concluding in a technological social contract as the backbone of the information and communication age.
Bitcoin adalah salah satu macam alat bayar yang diciptakan dan dikembangkan tidak di bawah otoritas apapun. Penggunaan Bitcoin berkembang dari tahun ke tahun dengan nilai pertukaran yang tinggi. Bahkan pada tahun 2018, nilai Bitcoin mencapai USD 19,783.06 per 1 (satu) Bitcoin yang mana nilai tersebut bersifat fluktuatif karena jumlah Bitcoin tersebut terbatas yakni hanya mencapai maksimal 21 juta (dua puluh satu juta). Terhadap popularitas Bitcoin tersebut, Bank Indonesia mengeluarkan pernyataan bahwa Bitcoin bukanlah alat pembayaran yang sah dan risiko penggunaan akan ditanggung sendiri oleh pengguna. Penelitian ini membahas mengenai keabsahan transaksi yang menggunakan Bitcoin jika alat bayarnya tersebut tidak sah. Penulis akan meninjau karakteristik Bitcoin sebagai uang virtual, Bitcoin sebagai mata uang dalam berbagai sisi, serta keabsahan transaksi Bitcoin jika dikaitkan dengan syarat perjanjian berdasarkan Kitab Undangundang Hukum Perdata. Terhadap transaksi menggunakan Bitcoin tersebut bertentangan dengan peraturan perundang-undangan yang berlaku. Dalam menjawab isu hukum yang ada, Penulis menggunakan pendekatan yuridis normatif dengan melakukan penelitian yang dikaji dari sumber hukum yang berlaku dengan menggunakan metode pendekatan konseptual dan pendekatan Undangundang.
James Kempf, Sambit Nayak, Remi Robert, Jim Feng · 9 authors
In this paper, we describe a virtual services marketplace, called Nubo, designed to connect buyers of virtual services (or tenants) with providers of those services on a cloud computing platform. The marketplace is implemented as a collection of distributed microservices along with a marketplace portal that runs as a Web application. The heart of Nubo is the Saranyu tenant and service management microservice. Saranyu is a decentralized application (dApp) built on top of the J.P. Morgan Quorum blockchain. Tenant and service accounts are represented as static (nonnegotiable) smart contracts written in the Solidity language. Quorum provides a tamper evident and tamper resistant distributed ledger, whereby multiple cloud and service providers can co-operate to provide service resources to tenants in a trustworthy fashion. Services offer resources consisting of a collection of attributes describing what the tenant can consume, and tenants subscribe to service resources through the Nubo Marketplace portal. The Service Manager microservice provides multitenant support for containerized services built for deployment and orchestration using Docker that were originally not designed to be managed through Saranyu. We discuss our design goals for Nubo, describe the overall architecture, discuss some details on how Saranyu uses the blockchain and smart contracts, and provide comprehensive performance and scalability data measured on the Saranyu REST API. The results indicate Saranyu is competitive with published results for comparable operations on the Havana release of OpenStack Keystone, but Saranyu provides a much richer collection of tenant and service management functionality than Keystone.
Marcos Vinicius M. R. Souza, Hélio Crestana Guardia
Advances in ubiquitous computing and in the Internet of things (IoT) bring new challenges to access control systems, such as not having to rely on a centralized trusted party, and the ability to use contextual data. Such characteristics may be required to enable IoT services in smart homes and cities, and in electronic health systems. In these environments, service-based device to device interactions reinforce the need for flexible and scalable authenticity and confidentiality mechanisms. This work presents an access control model to address such challenges using a blockchain infrastructure. In the proposed model, services and contextual data are defined using smart contracts, and blockchain logs are used for reliable information management. Assets are associated with permissions, and their transfers prove access control rights in service invocation requests. A reference implementation on Hyperledger shows the viability of the model.
When Satoshi Nakamoto released Bitcoin in 2009, the world became aware of blockchain technology, but cryptocurrency is just one of the applications that can be powered by blockchain technology. Blockchain technology2 is a distributed database where many copies of the data are replicated and synchronized. Don Tapscott (2016) describes the blockchain as “an incorruptible digital ledger of economic transactions that can be programmed to record not just financial transactions but virtually everything of value. [...] Blockchain differs from traditional ledgers of transactions in that it is decentralized, public and encrypted.”3Technology is becoming an integral part of creating, displaying, signing, and selling art. How is blockchain involved in the cycle of a work of art?In the following interview with Ruth Catlow (London, 1968), artist-theorist, curator, and co-founder and Artistic Director of Furtherfield4 and DECAL5(Decentralised Arts Lab), reflects on blockchain’s6 place in the art world and the importance of decentralized structures in art and economics. Focussing on critical investigations of digital and networked technologies and their emancipatory potential, she offers interesting insights into new economies, and suggests concepts for alternative ways to create new art practices.
Ajay Kumar Shrestha, Ralph Deters, Julita Vassileva
The tremendous technological advancement in the last few decades has brought many enterprises to collaborate in a better way while making intelligent decisions. The use of Information Technology tools in obtaining data of people's everyday life from various autonomous data sources allowing unrestricted access to user data has emerged as an important practical issue and has given rise to legal implications. Various innovative models for data sharing and management have privacy and centrality issues. To alleviate these limitations, we have incorporated blockchain in user modeling. In this paper, we constructed a decentralized data sharing architecture with MultiChain blockchain in the travel domain, which is also applicable to other similar domains including education, health, and sports. Businesses that operate in the tourism industries including travel and tour agencies, hotels and resorts, shopping malls are connected to the MultiChain and they share their user profile data via stream in the MultiChain. The paper presents the hotel booking service for an imaginary hotel as one of the enterprise nodes, which collects user profile data with proper validation and will allow users to decide which of their data to be shared thus ensuring user control over their data and the preservation of privacy. The data from the repository is converted into an open data format while sharing via stream in the blockchain so that other enterprise nodes, after receiving the data, can easily convert them and store into their own repositories. The paper presents an evaluation of the performance of the model by measuring the latency and memory consumption with three test scenarios that mostly affect the user experience. The node responded quickly in all of these cases.