A blockchain can be referred to as a collection of house, phone phone and rarity or it should be non-physical, for instance, offers of Associate in Nursing affiliation. It have to records or open record that gets shared amongst participating parties. Every transaction that gets incorporated is first verified by all the participants of that transaction. Once the data gets recorded by the blockchain, can never be rewritten or changed. Thus the blockchain can be termed as a record book of all the transactions held. Cryptocurrencies, the decentralized bitcoin or say ethereum which can be termed as peertopeer computerized cash also uses the blockchain technology. This paper includes history of bitcoin, a few literary reviews, working of the blockchain and its application.
Abstract Using extreme value analysis, we investigate the tail risk behavior of the high‐frequency (hourly) log returns of four most popular cryptocurrencies. The analysis is conducted on high‐frequency returns data, estimating value at risk and expected shortfall with varying thresholds. We find that Ripple is the most risky cryptocurrency exhibiting the largest potential gain or loss for both positive and negative (hourly) log returns at every percentile and threshold. Bitcoin is the least risky cryptocurrency.
Md. Mehedi Hassan Onik, Chul‐Soo Kim, Jinhong Yang
Fourth industrial revolution (Industry 4.0) promises a connected and smart manufacturing system where internet, machine (physical system) and humans lumped together. Unlike other industrial revolutions, this industrial revolution deals more with information. Device to device (D2D) and Machine to Machine (M2M) communications often generate, preserve and share private information. Personal data has already turned out to be a new commodity and currently identified as a ‘new oil’ or ‘new domain of warfare’. The more information gets generated and accumulated, the more extensive and risky the personal information becomes. Although privacy and security are often bundled together, they are different. This study investigates the privacy attack surfaces of key Industry 4.0 components (i.e. Cyber-Physical System, Artificial Intelligence, additive manufacturing, autonomous vehicle, big data, cloud computing, internet of things, distributed ledger etc). Multi-dimensional privacy challenges, data breaching incidents, regulations and need of a contextual privacy awareness is discussed in this study. Finally, this work elaborates the risk of Personally Identifiable Information (PII) leaking in the era of industry 4.0.
Open access
Blockchain Technology Applications and Security
Digital Transformation in Industry
Physical Unclonable Functions (PUFs) and Hardware Security
Jinliang Xu, Shangguang Wang, Bharat Bhargava, Fangchun Yang
Crowd-intelligence tries to gather, process, infer and ascertain massive useful information by utilizing the intelligence of crowds or distributed computers, which has great potential in Industrial Internet of Things (IIoT). A crowd-intelligence ecosystem involves three stakeholders, namely the platform, workers (e.g., individuals, sensors or processors), and task publisher. The stakeholders have no mutual trust but interest conflict, which means bad cooperation of them. Due to lack of trust, transferring raw data (e.g., pictures or video clips) between publisher and workers requires the remote platform center to serve as a relay node, which implies network congestion. First we use a reward-penalty model to align the incentives of stakeholders. Then the predefined rules are implemented using blockchain smart contract on many edge servers of the mobile edge computing network, which together function as a trustless hybrid human-machine crowd-intelligence platform. As edge servers are near to workers and publisher, network congestion can be effectively improved. Further, we proved the existence of the only one strong Nash equilibrium, which can maximize the interests of involved edge servers and make the ecosystem bigger. Theoretical analysis and experiments validate the proposed method respectively.
Pedro D. Manrique, Mason Klein, Yao Sheng Li, C. Xu · 6 authors
larvae seeking food), engineering (e.g., driverless navigation), medicine (e.g., reliable movement for brain-damaged individuals), and socioeconomics (e.g., bottom-up goal-driven human organizations). Centralized systems perform better with better components. Here, we show, by contrast, that a decentralized entity is more efficient at reaching a target when its components are less capable. Our findings reproduce experimental results for a living organism, predict that autonomous vehicles may perform better with simpler components, offer a fresh explanation for why biological evolution jumped from decentralized to centralized design, suggest how efficient movement might be achieved despite damaged centralized function, and provide a formula predicting the optimum capability of a system's components so that it comes as close as possible to its target or goal.
The article discusses the features of distributed ledger technology based on the use of decentralized peer-topeer networks. The history of the emergence and development of distributed ledger technology considered in detail, the prerequisites for the growth of its popularity in various fields are analyzed. The main advantages and disadvantages of distributed ledger technology in general, as well as decentralized (permissionless) and exclusive (permitted) blockchain platforms in particular, are revealed. The principles of functioning of cryptocurrencies on the basis of blockchain technology, including their issue (coinage) are described. The state of blockchain technologies from the point of view of technology maturity is considered. The main trends in the development of blockchain technology at the present stage are revealed. An analysis of the possibilities of using distributed ledger technology of public administration, including in the education system, in order to improve the safety and automation of functions is presented.
<sec> <title>BACKGROUND</title> Huge amounts of health-related data are generated every moment with the rapid development of Internet of Things (IoT) and wearable technologies. These big health data contain great value and can bring benefit to all stakeholders in the health care ecosystem. Currently, most of these data are siloed and fragmented in different health care systems or public and private databases. It prevents the fulfillment of intelligent health care inspired by these big data. Security and privacy concerns and the lack of ensured authenticity trails of data bring even more obstacles to health data sharing. With a decentralized and consensus-driven nature, distributed ledger technologies (DLTs) provide reliable solutions such as blockchain, Ethereum, and IOTA Tangle to facilitate the health care data sharing. </sec> <sec> <title>OBJECTIVE</title> This study aimed to develop a health-related data sharing system by integrating IoT and DLT to enable secure, fee-less, tamper-resistant, highly-scalable, and granularly-controllable health data exchange, as well as build a prototype and conduct experiments to verify the feasibility of the proposed solution. </sec> <sec> <title>METHODS</title> The health-related data are generated by 2 types of IoT devices: wearable devices and stationary air quality sensors. The data sharing mechanism is enabled by IOTA’s distributed ledger, the Tangle, which is a directed acyclic graph. Masked Authenticated Messaging (MAM) is adopted to facilitate data communications among different parties. Merkle Hash Tree is used for data encryption and verification. </sec> <sec> <title>RESULTS</title> A prototype system was built according to the proposed solution. It uses a smartwatch and multiple air sensors as the sensing layer; a smartphone and a single-board computer (Raspberry Pi) as the gateway; and a local server for data publishing. The prototype was applied to the remote diagnosis of tremor disease. The results proved that the solution could enable costless data integrity and flexible access management during data sharing. </sec> <sec> <title>CONCLUSIONS</title> DLT integrated with IoT technologies could greatly improve the health-related data sharing. The proposed solution based on IOTA Tangle and MAM could overcome many challenges faced by other traditional blockchain-based solutions in terms of cost, efficiency, scalability, and flexibility in data access management. This study also showed the possibility of fully decentralized health data sharing by replacing the local server with edge computing devices. </sec>
This paper is one of four in a series that reviews the potential application of blockchain technology in market-based instruments to improve transparency and, consequently, sustainability in the energy value chain in several jurisdictions.
The research in these four papers underpins “Blockchain for Governance of Sustainability Transparency in the Global Energy Value Chain” which can be found at:
https://ssrn.com/abstract=3236753.
In this paper, the author considers the legal and regulatory frameworks for India. From a regulation and policy perspective, the author explores challenges and possibilities for the use of blockchain technology for market based instruments for sustainability, specifically, green certificates and white certificates. The paper also considers the application of blockchain to improve transparency at various stages of the energy value chain.
Yuting Pan, Xiaosong Zhang, Yi Wang, Junhui Yan · 7 authors
This paper introduces the similarity between the mechanism of carbon trading and blockchain, then it elaborates on the application of blockchain in carbon trading. In corporate carbon trading, blockchain technology can record and transfer information flow reliably, realize point-to-point transactions between suppliers and demanders to achieve “decentralization”, help to reduce the entry threshold for the carbon trading market. At the same time, an analysis of social environment for blockchain-based carbon trading on person is made. Finally, the paper confirms the value of "blockchain + carbon trading" and looks forward to the future.
Blockchain is an innovative application model that integrates distributed data storage, peer-to-peer transmission, consensus mechanisms, digital encryption technology and other computer technologies. It is decentralized, secure, and Information disclosure. In the blockchain, digital encryption technology has a core position. The security of user information and transaction data is a necessary condition for the promotion of blockchain. The development of cryptography technology promotes and restricts the further development of blockchain. This paper outlines the infrastructure of blockchain, including the data layer, network layer, consensus layer, contract layer and application layer. The principles of encryption technology is introduced briefly, such as hash function, asymmetric cryptosystem, digital signature. The application of cryptography in all levels of blockchain is analyzed, including data layer, network layer, consensus layer, etc. It shows that cryptography runs through the whole blockchain system. The existing security problems of blockchain is analyzed, and the future research direction is expected.
Open access
Advanced Steganography and Watermarking Techniques
Roberto Tonelli, Maria Ilaria Lunesu, Andrea Pinna, Davide Taibi · 5 authors
Blockchain technologies and smart contracts are becoming mainstream research fields in computer science and researchers are continuously investigating new frontiers for new applications. Likewise, microservices are getting more and more popular in the latest years thanks to their properties, that allow teams to slice existing information systems into small and independent services that can be developed independently by different teams. A symmetric paradigm applies to smart contracts as well, which represent well defined, usually isolated, executable programs, typically implementing simple and autonomous tasks with a well defined purpose, which can be assumed as services provided by the Contract. In this work we analyze a concrete case study where the microservices architecture environment is replicated and implemented through an equivalent set of smart contracts, showing for the first time the feasibility of implementing a microservices-based system with smart contracts and how the two innovative paradigms match together. Results show that it is possible to implement a simple microservices-based system with smart contracts maintaining the same set of functionalities and results. The result could be highly beneficial in contexts such as smart voting, where not only the data integrity is fundamental but also the source code executed must be trustable.
This paper studies the design and management of distributed energy systems incorporating residential, commercial and industrial users. A hierarchical framework is first proposed for the energy demand side management through peer-to-peer exchange of information and energy in the real-time market. Smart contracts guaranteed by blockchain technologies are implemented to create a seamless and efficient trading system. The benefits of distributed energy management are presented such as economic savings, reduction of peak load and increased market efficiency facilitated by blockchain.
Blockchains were designed to solve the problem of double-spending in cryptocurrencies, and the success of the Bitcoin design has generated vastly more interest than previous proposals for digital currencies. Blockchains are being used in other areas as well, but the design choices that made blockchains effective for cryptocurrencies often do not fit well with other applications. In this paper we review the properties of distributed ledger technology (DLT) for use in typical data management applications and show how two recently developed distributed ledger ideas can be used to retain valuable aspects of blockchain while simplifying design and adding new but often necessary capabilities to permissioned distributed ledger applications. In particular, we are interested in the ability to delete or modify blocks, and the ability to provide a timestamping mechanism to provide a highly accurate time for applications that are time order dependent.
Yanni Georghiades, Steven Flolid, Sriram Vishwanath
Over the past five years, the rewards associated with mining Proof-of-Work blockchains have increased substantially. As a result, miners are heavily incentivized to design and utilize Application Specific Integrated Circuits (ASICs) that can compute hashes far more efficiently than existing general purpose hardware. Currently, it is difficult for most users to purchase and operate ASICs due to pricing and availability constraints, resulting in a relatively small number of miners with respect to total user base for most popular cryptocurrencies. In this work, we aim to invert the problem of ASIC development by constructing a Proof-of-Work function for which an existing general purpose processor (GPP, such as an x86 IC) is already an optimized ASIC. In doing so, we will ensure that any would-be miner either already owns an ASIC for the Proof-of-Work system they wish to participate in or can attain one at a competitive price with relative ease. In order to achieve this, we present HashCore, a Proof-of-Work function composed of "widgets" generated pseudo-randomly at runtime that each execute a sequence of general purpose processor instructions designed to stress the computational resources of such a GPP. The widgets will be modeled after workloads that GPPs have been optimized for, for example, the SPEC CPU 2017 benchmark suite for x86 ICs, in a technique we refer to as inverted benchmarking. We provide a proof that HashCore is collision-resistant regardless of how the widgets are implemented. We observe that GPP designers/developers essentially create an ASIC for benchmarks such as SPEC CPU 2017. By modeling HashCore after such benchmarks, we create a Proof-of-Work function that can be run most efficiently on a GPP, resulting in a more accessible, competitive, and balanced mining market.
Recently, enterprises have paid attention to permissioned blockchain (BC), where business transactions among inter-authorized organizations (forming a consortium) can automatically be executed on the basis of a distributed consensus protocol, and applications of BC have expanded as permissioned BC has adopted the features of the smart contract (SC), which is programmable user-defined business logic deployed in BC and executed with the consensus protocol. A single BC-based system will be built across multiple management domains (e.g., the data centers of each organization) having different operational policies (e.g., operational procedures, timing, etc.); although establishing system management and operations over BC-based systems (e.g., SC installation for updates) will be important for production uses, such multi-domain formation will trigger a problem in that executing system operations over BC-based systems will become time-consuming and costly due to the difficulty in unifying and/or adjusting operational policies. Toward solving the problem, we propose an operations execution method for BC-based systems; the primary idea is to define operations as a smart contract so that unified and synchronized cross-organizational operations can be executed effectively by using BC-native features. For the recent BC architecture in which participating nodes have different types of roles, we designed the proposed method as a hybrid architecture characterized with in-BC consensus establishment and execution status management and out-BC operations execution for all types of nodes operated by agents that listen to triggered events including operational instructions defined in SCs. We implemented a prototype with Hyperledger Fabric v1.2.0. A cost estimation with the prototype shows that the total yearly cost of SC installation operations could be reduced by 74 percent compared with a manual method.
Ingo Weber, Qinghua Lu, An Binh Tran, Amit Deshmukh · 6 authors
Blockchain has attracted a broad range of interests from start-ups, enterprises and governments to build next generation applications in a decentralized manner. Similar to cloud platforms, a single blockchain-based system may need to serve multiple tenants simultaneously. However, design of multi-tenant blockchain-based systems is challenging to architects in terms of data and performance isolation, as well as scalability. First, tenants must not be able to read other tenants' data and tenants with potentially higher workload should not affect read/write performance of other tenants. Second, multi-tenant blockchain-based systems usually require both scalability for each individual tenant and scalability with number of tenants. Therefore, in this paper, we propose a scalable platform architecture for multi-tenant blockchain-based systems to ensure data integrity while maintaining data privacy and performance isolation. In the proposed architecture, each tenant has an individual permissioned blockchain to maintain their own data and smart contracts. All tenant chains are anchored into a main chain, in a way that minimizes cost and load overheads. The proposed architecture has been implemented in a proof-of-concept prototype with our industry partner, Laava ID Pty Ltd (Laava). We evaluate our proposal in a three-fold way: fulfilment of the identified requirements, qualitative comparison with design alternatives, and quantitative analysis. The evaluation results show that the proposed architecture can achieve data integrity, performance isolation, data privacy, configuration flexibility, availability, cost efficiency and scalability.
Alberto Sonnino, Shehar Bano, Mustafa Al-Bassam, George Danezis
We present a family of replay attacks against sharded distributed ledgers, that target cross-shard consensus protocols, such as the recently proposed Chainspace and Omniledger. They allow an attacker, with network access only, to double-spend or lock resources with minimal efforts. The attacker can act independently without colluding with any nodes, and succeed even if all nodes are honest; most of the attacks can also exhibit themselves as faults under periods of asynchrony. These attacks are effective against both shard-led and client-led cross-shard consensus approaches. Finally, we present Byzcuit - a new cross-shard consensus protocol that is immune to those attacks. We implement a prototype of Byzcuit and evaluate it on a real cloud-based testbed, showing that our defenses impact performance minimally, and overall performance surpasses previous works.
At present times, there has been a surge in cryptopians community. Since wealth maximization is the aim of many, the virtual currency has become one of the important investment avenues. Virtual currency like bitcoins have become grill for the gossip mill. Consumer enjoys sovereignty. The present paper provides insight of the behind the scene technology in order to attain better understanding of the securitization prospects pertaining to the same. Mining allures cryptopians to solve proof of work because then only an increment in rewarded in blockchain. Without a doubt as per statistics, the currency has seen an upsurge but vital determinants which may pose a threat needs to be taken care of
Data Analytics in today's Demand Driven Supply chain Management (SCM) involving trusted as well as untrusted fulfilment partners will see exponential improvements with large volumes of reliable, trusted data generated automatically through IoT and stored in immutable format in the Blockchain. This paper examines the challenges which Supply Chain Partners in a Highly Digitized ecosystem have in getting access to good quality reliable data. It examines Use Cases and benefits of current IoT and Blockchain integrated frameworks for SCM. It also explores limitations of the traditional IoT and Blockchain integration patterns and presents an architectural framework for a permissioned Blockchain that can be used to overcome these limitations.
<sec> <title>BACKGROUND</title> Health care professionals are required to maintain accurate health records of patients. Furthermore, these records should be shared across different health care organizations for professionals to have a complete review of medical history and avoid missing important information. Nowadays, health care providers use electronic health records (EHRs) as a key to the implementation of these goals and delivery of quality care. However, there are technical and legal hurdles that prevent the adoption of these systems, such as concerns about performance and privacy issues. </sec> <sec> <title>OBJECTIVE</title> This study aimed to build and evaluate an experimental blockchain for EHRs, named HealthChain, which overcomes the disadvantages of traditional EHR systems. </sec> <sec> <title>METHODS</title> HealthChain is built based on consortium blockchain technology. Specifically, three organizations, namely hospitals, insurance providers, and governmental agencies, form a consortium that operates under a governance model, which enforces the business logic agreed by all participants. Every peer node hosts an instance of the distributed ledger consisting of EHRs and an instance of chaincode regulating the permissions of participants. Designated orderers establish consensus on the order of EHRs and then disseminate blocks to peers. </sec> <sec> <title>RESULTS</title> HealthChain achieves functional and nonfunctional requirements. It can store EHRs in a distributed ledger and share them among different participants. Moreover, it demonstrates superior features, such as privacy preservation, security, and high throughput. These are the main reasons why HealthChain is proposed. </sec> <sec> <title>CONCLUSIONS</title> Consortium blockchain technology can help to build new EHR systems and solve the problems that prevent the adoption of traditional systems. </sec>
<p class="ql-align-justify">A crypto-currency can be defined as a virtual monetary unit that is used via internet and not subject to the controls of any central authority or intermediary. These crypto-currencies can only be transferred from the virtual ledgers by using specific ciphers and can be used in a transaction via specific ciphers. In other words, individuals and institutions can make payments using these crypto-currencies just like other currencies. There are more than one thousand types of crypto-currencies. The purpose of this study is to find an answer for the question of whether these crypto-currencies could be the money of the future or a financial bubble like those examples in history. There is still no consensus on the value of crypto-currencies. Reliability and the superiority of blockchain technology are the strength of crypto-currencies, while its usage in money laundering, high transaction costs and problems with data mining are their weaknesses.
Diana Victoria Marcillo Parrales, Osvaldo Domínguez Junco
The autonomous decentralized governments of the cantons of Ecuador, as established by the Organic Code of Territorial Organization, Autonomy and Decentralization, are able to generate their own territorial policies. Public administrators, depending on compliance with the goals of economic reactivation and the internal market, must manage development programs in terms of growth in production and microenterprises. Public policies are an instrument that is used in the administrations of public bodies to achieve economic and social growth. The present research, carried out in the canton Jipijapa of Manabi Province in the Republic of Ecuador, allowed to determine the importance and impact that the public policies have in the development of the small and medium enterprises through the analytical descriptive method with a bibliographical revision from the theoretical approach. It identifies some of the existing public policies of a productive nature and their relationship with small and medium-sized enterprises. Their applicability and evaluation were analyzed with the efficiency, effectiveness and effectiveness indicators, a diagnosis was made applying surveys in microenterprises identified as object of study, and interviews with the political authorities of each decentralized autonomous government that make up or are part of the Jipijapa canton. To validate the results, statistical software Statistical Package for the Social Sciences (SPSS) version 22.0 was used. The existence of gaps that prevent the correct application of public policies and development programs was determined.
Referring to thefamous analogy which explains blockchain concept as “A wants to transfer moneyto B” the study reverses it as “B wants to have trade credit from A” then theparadigm will rather be crediting not debiting. To what extent will a supplierallow trade credit upon request is a decision of accounts payable, but theextent to which a third party will offer more trade credit for the firstborrower, will need a reconsideration of that customer’s liquidity which isrestricted by the already held accumulation of trade credit and/or bank creditas a potential. Trade credit and bank credit are main liquidity developers in atypical supply chain. The study reveals the need for a distributed ledger ofliquidity based on trade credit and proposes the use blockchain technology tocreate zones of private distributed ledgers for the liquidity based on tradecredit. In the future, the suggested zones are expected to cooperate withgovernment agencies and central bank in the challenge for eliminating informaltransactions within the economy. Hence, trade credit in the short-term andrelative liquidity indicators are presented in order to reveal the potentialfor an economy by giving evidence with the long-term data available in Turkey.The study depicts a conceptual proposal with the potential implicationstherein. Along with their blockchain challenge, the proposal in this study willstrategically favor the commercial banks which consider investing on such ashared ledger of liquidity especially in trade credits on firm-level.
Зоряна Двуліт, Khrystyna Peredalo, R. Tylipska, R. Terno · 5 authors
У статті розглянуто поняття "криптовалюта", обгрунтовано популярність цього нового виду фінансового інструменту на економічному просторі, виокремлено основні особливості криптовалюти як одного з виду віртуальних грошей та її вплив на економічну систему. Виокремлено такі ключові особливості криптовалюти: обмін на товари або послуги; обмін на класичну валюту; оплата товарів та послуг; мінімальний рівень неможливості викрадення; платежі, швидкі і прямі транзакції; інвестиційний актив; розвиток бізнесу на криптовалюті. Наведено переваги та недоліки криптовалюти та особливості її використання. Звернено увагу на Bitcoin, основний вид криптовалюти, який використовується в світі, та проаналізовано динаміку його курсу по відношенню до долара США. Розглянуто питання легалізації криптовалюти в окремих країнах, зокрема, в Україні. Визначено основні вимоги використання криптовалюти при її легалізації. Зосереджено увагу на українському законопроекті щодо порядку узаконення криптовалюти, що планується реалізувати в два етапи. Зроблено висновок про відсутність єдиної думки щодо подальшої стратегії розвитку криптовалюти в світі, її легалізації та законності використання. Наведено бачення щодо подальших тенденцій застосування криптовалюти у повсякденному житті та бізнес-середовищі. Проведено дослідження за проблемою розвитку ринку криптовалюти дозволило виокремити такі тенденції розвитку: нешвидке впровадження електронних грошей в усі сфери життя суспільства; можливість придбання усе більше товарів і послуг за крипто валюту; доповнення ринку фінансових послуг як новий платіжний інструмент та вид інвестиційних активів, не замінюючи при цього в найближчі роки, класичні банківські операції; зниження рівня анонімності при використанні криптовалюти, що буде зумовлено більшою її популяризацією; поширення легітимності криптовалюти у більшості державах світу; стабілізація курсу криптовалюти через 5—10 років; закріплення позицій Bitcoin як основної криптовалюти та поява нових, які досягатимуть масштабів Bitcoin.