This paper examines factors that influence prices of most common five cryptocurrencies such Bitcoin, Ethereum, Dash, Litecoin, and Monero over 2010-2018 using weekly data. The study employs ARDL technique and documents several findings. First, cryptomarket-related factors such as market beta, trading volume, and volatility appear to be significant determinant for all five cryptocurrencies both in short- and long-run. Second, attractiveness of cryptocurrencies also matters in terms of their price determination, but only in long-run. This indicates that formation (recognition) of the attractiveness of cryptocurrencies are subjected to time factor. In other words, it travels slowly within the market. Third, SP500 index seems to have weak positive long-run impact on Bitcoin, Ethereum, and Litcoin, while its sign turns to negative losing significance in short-run, except Bitcoin that generates an estimate of -0.20 at 10% significance level. Lastly, error-correction models for Bitcoin, Etherem, Dash, Litcoin, and Monero show that cointegrated series cannot drift too far apart, and converge to a long-run equilibrium at a speed of 23.68%, 12.76%, 10.20%, 22.91%, and 14.27% respectively.
In 2013, Farid and Vasiliev [arXiv:quant-ph/1310.4922] for the first time proposed a way to construct a protocol for the realisation of "{\em Classical to Quantum}" one-way hash function, a derivative of the Quantum one-way function as defined by Gottesman and Chuang [Technical Report arXiv:quant-ph/0105032] and used it for constructing quantum digital signatures. We, on the other hand, for the first time, propose the idea of a different kind of one-way function, which is "{\em quantum-classical}" in nature, that is, it takes an $n$-qubit quantum state of a definite kind as its input and produces a classical output. We formally define such a one-way function and propose a way to construct and realise it. The proposed one-way function turns out to be very useful in authenticating a quantum state in any quantum money scheme and so we can construct many different quantum money schemes based on such a one-way function. Later in the paper, we also give explicit constructions of some interesting quantum money schemes like quantum bitcoins and quantum currency schemes, solely based on the proposed one-way function. The security of such schemes can be explained on the basis of the security of the underlying one-way functions.
Many applications require the immutable and consistent sharing of data across organizational boundaries. Because conventional datastores cannot provide this functionality, blockchains have been proposed as one possible solution. Yet public blockchains are energy inefficient, hard to scale and suffer from limited throughput and high latencies, while permissioned blockchains depend on specially designated nodes, potentially leak meta-information, and also suffer from scale and performance bottlenecks. This paper presents CreDB, a datastore that provides blockchain-like guarantees of integrity using trusted execution environments. CreDB employs four novel mechanisms to support a new class of applications. First, it creates a permanent record of every transaction, known as a witness, that clients can then use not only to audit the database but to prove to third parties that desired actions took place. Second, it associates with every object an inseparable and inviolable policy, which not only performs access control but enables the datastore to implement state machines whose behavior is amenable to analysis. Third, timeline inspection allows authorized parties to inspect and reason about the history of changes made to the data. Finally, CreDB provides a protected function evaluation mechanism that allows integrity-protected computation over private data. The paper describes these mechanisms, and the applications they collectively enable, in detail. We have fully implemented a prototype of CreDB on Intel SGX. Evaluation shows that CreDB can serve as a drop-in replacement for other NoSQL stores, such as MongoDB while providing stronger integrity guarantees.
Blockchain technology, popularized by Bitcoin cryptocurrency, is characterized as an open-source, decentralized, distributed database for storing transaction information. Rather than relying on centralized intermediaries (e.g., banks) this technology allows two parties to transact directly using duplicate, linked ledgers called blockchains. This makes transactions considerably more transparent than those provided by centralized systems. As a result, transactions are executed without relying on explicit trust [of a third party], but on the distributed trust based on the consensus of the network (i.e., other blockchain users). Applying this technology to improve supply chain transparency has many possibilities. Every product has a long and storied history. However, much of this history is presently obscured. Often, when negative practices are exposed, they quickly escalate to scandalous, and financially crippling proportions. There are many recent examples, such as the exposure of child labor upstream in the manufacturing process and the unethical use of rainforest resources. Blockchain may bring supply chain transparency to a new level, but presently academic and managerial adoption of blockchain technologies is limited by our understanding. To address this issue, this research uses the Unified Theory of Acceptance and Use of Technology (UTAUT) and the concept of technology innovation adoption as a foundational framework for supply chain traceability. A conceptual model is developed and the research culminates with supply chain implications of blockchain that are inspired by theory and literature review.
We discuss the issue of what we call {\em incentive mismatch}, a fundamental problem with public blockchains supported by economic incentives. This is an open problem, but one potential solution is to make application portable. Portability is desirable for applications on private blockchains. Then, we present examples of middleware designs that enable application portability and, in particular, support migration between blockchains.
Lei Xu, Lin Chen, Zhimin Gao, Shouhuai Xu · 5 authors
Public blockchains provide a decentralized method for storing transaction data and have many applications in different sectors. In order for users to track transactions, a simple method is to let them keep a local copy of the entire public ledger. Since the size of the ledger keeps growing, this method becomes increasingly less practical, especially for lightweight users such as IoT devices and smartphones. In order to cope with the problem, several solutions have been proposed to reduce the storage burden. However, existing solutions either achieve a limited storage reduction (e.g., simple payment verification), or rely on some strong security assumption (e.g., the use of trusted server). In this paper, we propose a new approach to solving the problem. Specifically, we propose an \underline{e}fficient verification protocol for \underline{p}ublic \underline{b}lock\underline{c}hains, or EPBC for short. EPBC is particularly suitable for lightweight users, who only need to store a small amount of data that is {\it independent of} the size of the blockchain. We analyze EPBC's performance and security, and discuss its integration with existing public ledger systems. Experimental results confirm that EPBC is practical for lightweight users.
Blockchain is the core technology used to create the cryptocurrencies, like bitcoin. As part of the fourth industrial revolution since the invention of steam engine, electricity, and information technology, blockchain technology has been applied in many areas such as finance, judiciary, and commerce. The current paper focused on its potential educational applications and explored how blockchain technology can be used to solve some education problems. This article first introduced the features and advantages of blockchain technology following by exploring some of the current blockchain applications for education. Some innovative applications of using blockchain technology were proposed, and the benefits and challenges of using blockchain technology for education were also discussed.
This paper outlines key design principles of Scilla---an intermediate-level language for verified smart contracts. Scilla provides a clean separation between the communication aspect of smart contracts on a blockchain, allowing for the rich interaction patterns, and a programming component, which enjoys principled semantics and is amenable to formal verification. Scilla is not meant to be a high-level programming language, and we are going to use it as a translation target for high-level languages, such as Solidity, for performing program analysis and verification, before further compilation to an executable bytecode. We describe the automata-based model of Scilla, present its programming component and show how contract definitions in terms of automata streamline the process of mechanised verification of their safety and temporal properties.
The public sector presents several promising applications for blockchain technology. Global organizations and innovative ministries in countries such as Dubai, Sweden, Finland, the Netherlands, and Germany have recognized these potentials and have initiated projects to evaluate the adoption of blockchain technology. As these projects can have a far-reaching impact on crucial government services and processes, they should involve a particularly thorough evaluation. In this paper, we provide insights into the development of a framework to support such an evaluation for the German asylum process. We built this framework evolutionarily together with the Federal Office for Migration and Refugees. Its final version consists of three levels and eighteen categories of evaluation criteria across the technical, functional and legal domains and allows specifying use-case specific key performance indicators or knockout criteria.
Jia Bainga Kangbai, P. Rohini Bai, Sulaiman Mandoh, Abu Bakarr Fofanah · 8 authors
Objective: In the absence of any approved therapeutics and vaccines to treat or prevent Ebola infection, managing Ebola outbreak largely depends on early case detection and surveillance, real-time communication of surveillance data, and Ebola case management. Here we assessed the possibility of uploading data obtained by Internet of Internet device that monitors cellphone company’s Call Data Records (CDR), national demographic census, national transportation system and Ebola vaccine production databases on a Blockchain platform to conduct real-time Ebola contact tracing, transmission pattern surveillance and vaccine delivery. Results: Mobility data obtained by Internet of Things (IoT) from CDR from cellphone companies, national transportation system, and census demographic data can be integrated into a Blockchain platform to provide real-time Ebola surveillance and contact-tracing. While cellphone data provides a unique opportunity to quantify human mobility, Blockchain system magnifies such opportunity by making the data accessible to many actors in real-time. By mounting data from CDR, national population census, national transport system and Ebola vaccine production database on a Blockchain platform will provide additional lens in our understanding of the role played by human population dynamics in the spread as well and containment of Ebola during outbreaks
The development of Energy-Internet is currently suffering from a series of issues, such as the conflicts among high capital requirement, low-cost, high efficiency, the spreading gap between capital demand and supply, as well as the lagged trading & valuation mechanism, any of which would hinder Energy-Internet's evolution. However, with the development of Blockchain and big-data technology, it is possible to work out solutions for these issues. Based on current situation of Energy-Internet and its requirements for future progress, this paper demonstrates the validity of employing blockchain technology to solve the problems encountered by Energy-Internet during its development. It proposes applying the blockchain and big-data technologies to pricing and trading energy products through Energy-Internet and to accomplish cyber-based energy or power's transformation from physic products to financial assets.
Abid Sultan, Muhammad Sheraz Arshad Malik, Azhar Mushtaq
Since the beginning of crypto currency in 2008, blockchain technology rise as progressive technology. Despite the fact that blockchain began off as a core technology of Bitcoin, its utilization cases are growing to numerous fields such as, security of Internet of Things (IoT), banking sector, industries and medical etc. In recent years IoT has gained popularity due to its usage in smart homes and smart city projects around the world. Unfortunately, IoT devices possess limited computing power, low storage capability and network capacity therefore they are more prone to attacks than other endpoint devices such as cell phones, tablets, or PCs. This paper focus on significant security issues for IoT, security prerequisites for IoT alongside the current attacks and maps IoT security issues against existing solutions found in the literature. Blockchain technology can be a key empowering influence to take care of numerous IoT security issues. Finally describe the future work directions.
The convergence of the physical and virtual worlds radically challenges our legal, economic and other institutional regimes. In contrast, property rights and transaction cost regimes are still largely based on the pre-digital era. The blockchain architecture seems to offer a way for one Internet user to safely and securely transfer a unique piece of digital property to another in such a way that anyone knows that the transfer has taken place and no one can challenge the legitimacy of the transfer. Subsequently, transaction costs could diminish and property rights be unbundled and partially enforced on an unprecedented granular level. This paper explores the implications of blockchain technology for our established property rights and transaction cost regimes. It aims to discuss whether the established regimes and theories will prevail or will need to adapt to the advent of blockchain technology.
Blockchain is a new, foundational technology with a vast amount of application possibilities. However, practitioners might not be aware of which use cases in their own business model might benefit from blockchain technology. To aid them in analyzing their business regarding blockchain suitability, this paper introduces a use case identification framework for blockchain and a use case canvas. In the development process they have been evaluated with internal and external reviews in order to offer the best possible guidance. In combination they offer an analysis framework to help practitioners decide which use cases they should take into account for blockchain technology, which characteristics these blockchain implementations would have, and which specific advantages they would offer.
I consider a developer working on an open-source blockchain-based software that can be used only in conjunction with a specific crypto-token. This token can be sold in an Initial Coin Offering (ICO) to raise funds, but can also be sold later on a frictionless financial market to earn a profit. I show that, if the developer raises funds in an ICO, in each post-ICO period there is a positive probability that the developer sells all of his tokens on the market and, as a consequence, no development occurs. If the developer does not need to raise funds via an ICO, the equilibrium will nonetheless be inefficient because the developer's payoff depends on the surplus generated by the protocol in a given period (when he expects to sell his tokens). He therefore fails to internalize that the protocol will be used (and generate surplus) over multiple periods.