The aim of the article is to research the prospects and opportunities for using blockchain technology in entrepreneurship, as well as international payments and banking operations. On the basis of current and up-to-date data and opinions of authoritative English-language publications on business, the problems concerning the relevance of technology of a distributed ledger have been comprehensively examined, and the results of many startups â young companies working on blockchain-solutions in various spheres, have been evaluated. As a result of the research, the main directions of work of startups in the field of application of blockchain technology were identified: smart contracts; cloud data storage; production processes; sphere of remuneration of employees; electronic voting with protection against breaking; "sharing economy". Prospects for further research in this direction are specific justification of the applicability of distributed ledger technology and the concept of decentralization in developing sectors (the "sharing economy", "Internet of Things"), as well as a deeper analysis of the impact of new solutions in relation to the traditional sectors of the economy, including Ukraine.
Hao Xu, Long Yu, Liu Zhiqiang, Zhen Liu ¡ 5 authors
This paper describes a novel Byzantine fault tolerant protocol that allows replicas to join and exit dynamically. With the astonishing success of cryptocurrencies, people attach great importance in âblockchainâ and robust Byzantine fault tolerant (BFT) protocols for consensus. Among the conventional wisdom, the Practical Byzantine Fault Tolerance (PBFT), proposed by Miguel and Liskov in 1999, occupies an important position. Although PBFT has many advantages, it has fatal disadvantages. Firstly, it works in a completely enclosed environment, where users who want to add or take out any node must stop the whole system. Secondly, although PBFT guarantees liveness and safety if at most [n-1/ 3] c out of a total n replicas are faulty, it takes no measure to deal with these ineffective or malicious replicas, which is harmful to the system and will cause system crash finally. These drawbacks are unbearable in practice. In order to solve them, we present an alternative, Dynamic PBFT.
Blockchain technology has the potential to decentralise many traditionally centralised systems. However, scalability remains a key challenge. A horizontally scalable solution, where performance increases by adding more nodes, would move blockchain systems one step closer to ubiquitous use. We design a novel blockchain system called CHECO. Each node in our system maintains a personal hash chain, which only stores transactions that the node is involved in. A consensus is reached on special blocks called checkpoint blocks rather than on all transactions. Checkpoint blocks are effectively a hash pointer to the personal hash chains; thus a single checkpoint block may represent an arbitrarily large set of transactions. We introduce a validation protocol so that any node can check the validity of any transaction. Since transaction and validation protocols are point-to-point, we achieve horizontal scalability. We analytically evaluate our system and show a number of highly desirable correctness properties such as consensus on the validity of transactions. Further, we give a free and open-source implementation of CHECO and evaluate it experimentally. Our results show a strong indication of horizontal scalability.
Jack Doerner, Yashvanth Kondi, Eysa Lee, Abhi Shelat
The Elliptic Curve Digital Signature Algorithm (ECDSA) is one of the most widely used schemes in deployed cryptography. Through its applications in code and binary authentication, web security, and cryptocurrency, it is likely one of the few cryptographic algorithms encountered on a daily basis by the average person. However, its design is such that executing multi-party or threshold signatures in a secure manner is challenging: unlike other, less widespread signature schemes, secure multi-party ECDSA requires custom protocols, which has heretofore implied reliance upon additional cryptographic assumptions such as the Paillier encryption scheme. We propose new protocols for multi-party ECDSA key-generation and signing with a threshold of two, which we prove secure against malicious adversaries in the random oracle model using only the Computational Diffie-Hellman Assumption and the assumptions already implied by ECDSA itself. Our scheme requires only two messages, and via implementation we find that it outperforms the best prior results in practice by a factor of 55 for key generation and 16 for signing, coming to within a factor of 12 of local signatures. Concretely, two parties can jointly sign a message in just over two milliseconds.
The attempts to create an adequate model of socio-economic critical events, which, as it has been historically proven, are almost permanent, were, are and will always be made. Actually, it is a supertask, impossible to solve. However, the potentially useful solutions, local in time or other socio-economic logistic coordinates, are possible. In fact, they have to be the object of interest for a real and effective economic science. Econophysics is a young interdisciplinary scientific field, which developed and acquired its name at the end of the last century. Quantum econophysics, a direction distinguished by the use of mathematical apparatus of quantum mechanics as well as its fundamental conceptual ideas and relativistic aspects, developed within its boundaries just a couple of years later, in the first decade of the 21-st century.
Robert Alexandru Dobre, Radu Preda, Claudia Cristina Oprea, IonuĹŁ Pirnog
Image authentication importance increases as image acquisition becomes easier with the help of new technologies. Today, almost any phone has a camera with decent performances and sharing images is encouraged by social media. Image tampering is also decreasing in difficulty because of the advances in image editing software. Today's signature-based image authentication techniques rely on storing the image signature until the authentication is needed. This is a disadvantage because the storage support is usually unique, controlled by one entity and could fail. Also, this centralized approach is not fundamentally trustworthy. To solve these problems, the paper proposes a signature-based image authentication method resistant to JPEG compression which makes use of new blockchain technology to store the image signature. With this method, the signature is stored in a decentralized network, significantly increasing the security.
Advanced Steganography and Watermarking Techniques
Wireless Sensor Networks (WSN) interconnects thousands of sensor nodes to support the services of Internet of Things (loT). However, data collected from sensor nodes may be tempered, forged and divulged. Traditional WSN data process platform handle the data centralized in terminal devices which is vulnerable to attacks and reduce the security of the system. Blockchain is a kind of distributed databases. It has been successfully applied in finance, securities, digital currency and other fields. We first propose a blockchain-based distributed collocation storage architecture for data security process platform of WSN with consensus protocol and asymmetric signature scheme. The security and efficiency are verified on the simulation to enable blockchain as a good solution.
The technology of blockchain (âBlockchainâ) realises a more efficient, equitable, and transparent distributed ledger system. An important characteristic of Blockchain is its automated, de-centralized, and neutral ledger system which could be useful to carry out Corporate Social Responsibility (âCSRâ) initiatives. Part I of this paper suggests that the Blockchain will evolve to become a permanent âdisruptorâ with the potential to transform corporationsâ CSR practices. Part II introduces the Blockchain and identifies its significance to CSR, both in the United States (âU.S.â) and internationally. Part III explains how the Blockchain can help demonstrate that a corporation is a âresponsible businessâ through good corporate governance, effective supply chain management, and exercise of the triple bottom line â people, profit, and planet. Part IV examines how the Blockchainâs disruptive role influences corporate decision-making, especially its implications for corporate investors, financial institutions, and the practice of law as well as its impact on intellectual property and data privacy functions. Part V discusses the U.S. current regulatory landscape and growing trends relating to the Blockchain. Finally, Part VI recommends lawmakers and corporations consider adopting a legislative framework that aligns with the United Nations Sustainable Development Goals (âUN SDGsâ) to demonstrate responsible investment and good corporate governance. Accordingly, the Blockchain can help corporations transform CSR practices and assist lawmakers to regain public trust through effective rulemaking that demands corporate accountability on domestic and international issues.
Under the background of rapid development of distributed renewable energy (DRE) and demand response (DR), the traditional DR will develop into integrated demand response (IDR). The current centralized trading of electricity market model is unable to meet the trading needs of scattered IDR resources. As the decentralized and distributed accounting mode, the blockchain technology fits the requirement of IDR resources to participate in energy market. The blockchain-based DRE transaction platform can support the credible transaction and settlement between the IDR resources, and promote the development of DER. Corresponding to the transaction principle, the frame of blockchain-based IDR resources transaction scheme was proposed. The transactions between DER and DR are taken for example to explain the detail trading process. Finally, the smart contracts of the transactions are designed and deployed on Ethereum private blockchain to prove the validity of the proposed transaction scheme.
As digital innovations such as artificial intelligence, cloud computing, automation, and the Internet of Things (IoT) become more readily usable, energy companies are developing strategies that incorporate these burgeoning systems into their operational infrastructure. Distributed ledger technologyâotherwise known as blockchainâmay be the backbone of this new infrastructure. Already well-known in the financial sector, blockchain is a peer-to-peer (P2P) network technology that uses advanced computer science techniques to enable trustworthy interactions between parties, even if those parties do not trust each other. It is a shared electronic ledger in which access can be managed by multiple sources, including anonymous ones. Proponents say blockchain is reliable and likely to change the way in which energy companies perform transactions. Operators are already working with various blockchain platforms, but the developers of these platforms are still forging a path that they hope will lead to widespread adoption within the industry. The Mechanics of Blockchain Fig. 1 illustrates the basics of a blockchain platform. An entity requests a transaction, the transaction is broadcast to a P2P network, validated, combined with other transactions to create a block of data within a ledger, and added to a chain of previous transactions in a way that is permanent and unalterable. These transactions can represent anything, from the exchange of numbers of digital assets to the acceptance of a trade of a digital commodity that can be audited by a third party for authenticity without revealing sensitive information. The blockchain ledger can be shared with all members at all times. It is not stored in one place, and there is full transparencyâcompanies can control exactly which information gets shared and with whom. A blockchain entry can include executable computer code that reflects the terms of the contract, creating a smart contract that automatically validates transactions without the need for human intervention. A smart contract selfexecutes code that enables straight-through processing and eliminates the need for manual intervention in the execution of a transaction. Smart contracts can mimic regular contracts and execute the contract automatically if the conditions required to consummate the contract are met. Jerry Bailey, director and president of Petroteq and a former senior executive engineer at Exxon, compared blockchain to traditional means of storing information. âWe all have had big file cabinets, big file rooms all through the years,â Bailey said. âYou go into a file room and find dozens of file cabinets. Everybody had a key to the file room but not everybody had a key to each of the file cabinets, depending on what their part in the company was. Blockchain is like this to me. It sets up a system where not only the company, but our vendors, our suppliers, and our buyers can look into the appropriate file cabinet, as it were.â
It is a very tiring process for people to watch the multiple parallel instant price changes in stock exchanges that are rapidly changing like the crypto money market. As a solution to this, a computer software that can make quick and objective decisions by constant observation can take the place of a person. In this study, an original decision algorithm that evaluates the instantaneous values of price change indicators and obtains relatively high earnings in a short period of time is examined. The Python programming language and Mathlib library have been used to construct this algorithm and to visualize the data, Moving Average Convergence Divergence (MACD) and Bollinger Bands have been used as a basic indicator. The result is an algorithm that requires less processing power and can operate continuously even on ARM-based mini-computers.
Electronic health records may have digitized patient data, but getting that data from one clinician to another remains a huge challenge, especially since patients often have multiple doctors ordering tests, prescribing drugs, and providing treatment. Many experts now believe that blockchain technology might be just the thing to get a patient's pertinent medical information from where it is stored to where it is needed, as well as to allow patients to easily view their own medical histories. In addition, blockchain technology might also be able to help with other aspects of health care, such as improving the insurance claim or other administrative processes within healthcare networks and making health-related population data available to biomedical researchers.
Objectives: Incorporating new technologies into the development of smart cities means rethinking the way different services are provided. From this perspective, Blockchain might represent the future of both smart cities and smart communities as it offers new alteratives for individuals and institutions.
The East Asian cryptocurrency market has burgeoned in the past few years, especially in Japan, China, and South Korea. This means that more and more people are involved in dealings over this novel form of âeconomic valueâ. But, what exactly are people selling and buying? Traditionally, things can be divided into moveables (i.e., tangible things such as books, physical money such as coins or notes, or intangible things such as debts etc.) and immoveables (i.e., land). While the rules pertaining to transactions in such traditional things are well recognised, the same cannot be said of cryptocurrencies. The uncertainty of their characterisation renders it difficult to be confident in transaction finality as a matter of law and also potentially exacerbates dispute resolution. Two issues merit exploration: Is a cryptocurrency a thing as such? If so, can it be the object of a property right? Many other relevant legal issues concerning cryptocurrencies (i.e., how they are protected by law, the legal rules relating to their transfer, or systematic deployment etc.) would hinge upon the above two fundamental issues. Their characterisation may also be significant for conflict of laws characterisation purposes as many of the essential infrastructure for the trading of cryptocurrencies (e.g., mining and exchanges) are located in East Asia. This Chapter aims to survey the major East Asian civil law jurisdictions (i.e. Japan, China, and South Korea) to ascertain how they may address these questions in the light of their respective laws.
Sushmita Ruj, Mohammad Shahriar Rahman, Anirban Basu, Shinsaku Kiyomoto
In order to ensure faster audits, higher transparency and security, many applications are being designed using blockchains. We propose BlockStore, a secure decentralized storage framework using blockchain technology. The primary motivation is efficient utilization of storage resources of users. Users often have un-utilized or underutilized storage in their devices. They can choose to host their storage resources when they are not in use. Users rent storage from the host for a fee for a fixed period of time and release back after the time expires. BlockStore keeps track of un-utilized storage of hosts in Space Wallet, a structure that helps in assigning storage to renters on request. The ownership of storage can be proved by logging all storage transactions in a public ledger (the blockchain), which can be verified by any user. A host cannot host the same storage to two users at the same time, nor can it tamper with the data of the renter. Renters cannot frame a host of cheating. BlockStore uses proofs of storage and data possession to verify that the hosts do not tamper with data and penalizes parties for misbehavior. Users can encrypt data for privacy. Payment and penalty are handled using smart contracts. BlockStore differs from existing solutions, by providing stronger audit that detects and penalizes misbehaving parties earlier than existing schemes.
Ransomware is a type of malware that encrypts the files of infected hosts and demands payment, often in a crypto-currency like Bitcoin. In this paper, we create a measurement framework that we use to perform a large-scale, two-year, end-to-end measurement of ransomware payments, victims, and operators. By combining an array of data sources, including ransomware binaries, seed ransom payments, victim telemetry from infections, and a large database of bitcoin addresses annotated with their owners, we sketch the outlines of this burgeoning ecosystem and associated third-party infrastructure. In particular, we are able to trace the financial transactions, from the acquisition of bitcoins by victims, through the payment of ransoms, to the cash out of bitcoins by the ransomware operators. We find that many ransomware operators cashed out using BTC-e, a now-defunct Bitcoin exchange. In total we are able to track over $16 million USD in likely ransom payments made by 19,750 potential victims during a two-year period. While our study focuses on ransomware, our methods are potentially applicable to other cybercriminal operations that have similarly adopted Bitcoin as their payment channel.
In order for malicious software to receive configuration information or commands, malware needs to be able to locate and connect to its owner. As hard-coded addresses are easy to block and thus render the malware installation inoperable, malware writers have turned to dynamically generated addresses. Domain generation algorithms (DGA) generate a list of candidate domain names, each valid for only a short time, at which the malware installation searches for its command & control (C&C) server. As DGAs generate a large list of potential domains - out of which one or a few is actually in use -, they leave a characteristic trace of many failed DNS lookups (NXDomain) in the network, and in result most DGAs can be efficiently detected. In this paper we describe an entirely new principle of domain generation, actively deployed in the Cerber ransomware, which finds and coordinates with its owner based on transaction information in the bitcoin blockchain. This allows the malware author to dynamically update the location of the server in realtime, and as the malware directly goes to the right location no longer generates a sequence of NXDomain responses. We describe the concept of coordination via the blockchain, and report results on a year-long observation of the assets used in the Cerber campaign.
The second meeting of ISO/TC 307 (International Organization for Standardization Technical Committee 307: blockchain and electronic distributed ledger technologies) was held in Tokyo in November 2017.This TC is working to develop international standards for blockchain technology.This article introduces the concept of blockchain technology-the fundamental technology used for bitcoin-as well as trends in the international standardization of electronic distributed ledger technologies and some applications of blockchain technology beyond cryptocurrency.
There are a lot of blockchain platform implementations available today. To be integrated into the smart space for Industrial IoT the blockchain platform should support not only token exchange but also smart contract distribution and launching, fault tolerance consensus mechanism and equivalence between participants to create and implement new blocks and contracts. The paper provides analysis of the most used consensus mechanisms, specific features of public (permissionless) and private (permissioned) blockchains. Also a description of blockchain platforms that satisfy the requirements for the IIoT platform development is provided. By the result of the analysis the platform and specific modules have been selected for implementation of blockchain for industrial IIoT platform.
Nicholas Stifter, Aljosha Judmayer, Philipp Schindler, Alexei Zamyatin ¡ 5 authors
The term Nakamoto consensus is generally used to refer to Bitcoinâs novel consensus mechanism, by which agreement on its underlying transaction ledger is reached. It is argued that this agreement protocol represents the core innovation behind Bitcoin, because it promises to facilitate the decentralization of trusted third parties. Specifically, Nakamoto consensus seeks to enable mutually distrusting entities with weak pseudonymous identities to reach eventual agreement while the set of participants may change over time. When the Bitcoin white paper was published in late 2008, it lacked a formal analysis of the protocol and the guarantees it claimed to provide. It would take the scientific community several years before first steps towards such a formalization of the Bitcoin protocol and Nakamoto consensus were presented. However, since then the number of works addressing this topic has grown substantially, providing many new and valuable insights. Herein, we present a coherent picture of advancements towards the formalization of Nakamoto consensus, as well as a contextualization in respect to previous research on the agreement problem and fault tolerant distributed computing. Thereby, we outline how Bitcoinâs consensus mechanism sets itself apart from previous approaches and where it can provide new impulses and directions to the scientific community. Understanding the core properties and characteristics of Nakamoto consensus is of key importance, not only for assessing the security and reliability of various blockchain systems that are based on the fundamentals of this scheme, but also for designing future systems that aim to fulfill comparable goals.
Gultekin Berahan Mermer, Engin Zeydan, Ĺuayb S. Arslan
Blockchain is a recently emerging technology that has the potential to revolutionize the way society interacts and trades between each other. The main advantage this technology provides is its ability to exchange transactions without relying on a trusted third party entities of any means. It can also provide data integrity, in-built authenticity and user transparency. Blockchain is envisioned to be the new internet on which many revolutionary applications will be based. In this work, we provide an overview of blockchain technologies including their principles, opportunities and challenges ahead.
Abstract Cryptocurrencies have experienced an exponential growth trend in the past 24 months, followed by a big crash. In the early years of the Internet, inspired entrepreneurs such as Jeffrey Bezos realized that, when something grows exponentially, it becomes ubiquitous within a short time span. Similarly to the Internet in 1994, cryptocurrencies have recently been growing at a dazzling rate, thus one can expect them to be used on a global scale very soon, in spite of the last bubble which has already burst. Alternative currencies are greeted with great enthusiasm, due to their potential to return financial power back to the people, especially in the context of general dissatisfaction and disappointment with the banking sector. They bring about several advantages, such as financial innovations, lower fees as well as increased availability to developing populations. At the same time, their high volatility and lack of supervision might imply that they only serve as complementary financing and not as a substitute of traditional banking. This article discusses the development of cryptocurrencies, including aspects related to Bitcoin, financial technology and the blockchain. Using historical data from Coinmarketcap.com between April 2013 and February 2018, I run a quantitative analysis of the distributions and evolution over time for all listed cryptocurrencies with known market capitalization. I look at the interplay between number of cryptocurrencies and market value, at growth rates, cumulative shares and volatility. I find a phenomenon of exponential growth and violent volatility, which I explain in light of cryptocurrenciesâ strengths and weaknesses, as identified in the literature. I emphasize the importance of cryptocurrencies in the context of the global digital economy and I discuss future implications.