Block chain technology has occupied a very important position in today's society. This emerging technology has been successfully explored and developed in many fields and scenarios. However, due to the fact that block chain technology is still in the exploratory stage, there is no rigid specification and index for block chain products, Integrating the research results of block chain technology architecture and security risk assessment, this paper designs a set of evaluation indicators for block chain products. The indicators are divided into six aspects, including P2P network technology evaluation index, distributed ledger technology evaluation index, asymmetric encryption technology evaluation index, smart contract evaluation index, consensus mechanism evaluation index and other security technologies Evaluation indicators, each big evaluation index is subdivided into several more in-depth evaluation indicators, and each of the specific analysis and explanation. Finally, based on the previous analysis and design work, a block chain product evaluation software is developed, which provides users with the function of comprehensive evaluation of block chain products. The design and software implementation of the block chain product evaluation system can effectively improve the efficiency in the development of block chain products and the quality of the products themselves, which is conducive to the further development of the block chain field.
Blockchain or Distributed Ledger Technology (DLT) introduces a new computing paradigm that is viewed by experts as a disruptive and revolutionary technology. While bitcoin is the most well-known successful application of blockchain technology, many other applications and sectors could successfully utilize the power of blockchain. The potential applications of blockchain beyond finance and banking encouraged many organizations to integrate and adopt blockchain into existing or new software systems. Integrating and using any new computing paradigm is expected to affect the best practice and design principles of building software systems. Emerging blockchain-based applications require careful attention to many functional and nonfunctional requirements. One common practice in software engineering to handle potential pitfalls in software systems is using design patterns. Design patterns have been long used in software development to optimize the quality of software being developed. This research aims to determine the level of adoption of design patterns blockchain applications and their usefulness by analyzing the quality of the source code. This is achieved in a two-step process. Firstly, the quality of publicly available blockchain-based applications developed with design patterns is compared with applications without design patterns. In the next step, two versions of a blockchain-based application for cheque clearance are developed, with and without design patterns, and their quality and vulnerability to attacks are compared.
Managing medical device monitoring processes is challenging and lacks a realtime, life cycle tracking strategy to reduce adverse medical events and revision costs for hospital administrators, physicians, and patients. Understanding the malfunctions of medical devices for cardiac and orthopedic patients could save lives and reduce hospital liability. Grounded in the business process reengineering conceptual framework, the purpose of this single qualitative case study was to explore strategies hospital managers used to redesign the implant recall surveillance process at one hospital in Pennsylvania. The 5 participants selected successfully implemented a medical device surveillance process that reduced adverse medical events and revision costs. Data were collected using semistructured interviews and a review of relevant medical device surveillance workflow documents. The 4 themes that emerged from a thematic analysis were effective data communication process, central data repository integration, continuous process improvement, and end-to-end surveillance process. A key recommendation for hospital administrators, physicians, and managers is to use blockchain distributed ledger technology to assess device identification challenges as part of the surveillance process to reduce health risks. The implication for positive social change includes the potential to improve the quality of life for medical device recipients who may spend less on healthcare services.
Blockchain is an innovative technology which is used by cryptocurrencies as a public, immutable ledger for recording transactions, while more recent versions of Blockchain can also record smart contracts and other assets. Blockchain can be viewed as a distributed platform that holds transactional records without the involvement of a central authority, and where ensuring decentralization, transparency and security is of paramount importance. But the transparency requirement, absolutely necessary for improving trust among the blockchainâs users, came with a price: lack of privacy. In most of the blockchains which are based on Bitcoinâs Blockchain, anyone can query the blockchain and see all the transactions. This introduces a privacy issue which needs to be addressed. Although there are a few solutions for mitigating the privacy concern, we consider that true anonymity must be built-in, not added on trough extensions to the base protocol. We propose a novel solution, called RandAdminSuite, that addresses the blockchain privacy problem through a comprehensive approach that covers the blockchain architecture itself, transaction mechanism and cryptocurrency as well. RandAdminSuite offers some improvements over the concept of currency rewards for transaction processing nodes.
This thesis aims to add knowledge that contributes to answering the question of how digital transformation technologies can contribute to increasing customer value in logistics and supply chain management (L&SCM), and how manufacturing companies can mindfully use them. The output of the thesis is an architectural framework that proposes performance components, approaches and methodologies that can help in capturing this customer value. To build the basis for such a framework, this research first deduces and presents the underlying definition of digital transformation and describes its potential for, as well as current barriers for its application in, L&SCM. The study uses a systematic literature review to identify nine underlying digital transformation technology bundles. These are: auto-identification technologies; information and communication technologies; the cloud; cyber physical systems; analytics; distributed ledger; automation technologies; augmented and virtual reality; and additive manufacturing. These technologies served as inputs for a nominal group technique workshop aiming to conceptualize the dimensions of customer value based on the technologies. The derived dimensions are information disclosure, time, product/production, service/assistance, quality, choice options, and planning. Based on these findings, this thesis presents an impact assessment for customer-based L&SCM performance. The three-plus-one customer value propositions are availability, servitization, co-creation, and cognition as enhancement. Expert interviews provide the data for the architectural framework for capturing customer value based on digital transformation technologies in L&SCM. The six dimensions covered are the customer value proposition; the value portfolio; scope of collaboration; human resource management and organization; performance management; as well as the (re-)adjusting value assessment. The main scientific contribution lies in conceptualizing the customer value for L&SCM based on digital transformation technologies whereas the architectural framework constitutes the main practical contributions.
Sen Liu, Yanan Hu, Xiao Zhang, Yanfeng Li · 5 authors
The emergence of blockchain technology has significantly changed the underlying infrastructure of existing information technology and will fundamentally affect the production modes of enterprises. However, because the application of blockchain is still in its infancy, it is difficult for an enterprise to develop a comprehensive assessment of various types of blockchain service providers in the market. Hence, enterprises need scientific decision tools to estimate which blockchain service provider is appropriate. However, few studies have focused on this phenomenon. Therefore, to address this challenge, this investigation proposes a novel integrated multi-attribute group decision-making (MAGDM) method to help enterprises estimate which blockchain vendor is more appropriate by considering more comprehensive influence factors. The proposed method is defined in an intuitionistic fuzzy environment and integrates entropy and the best-worst method (BWM) for comprehensive weighting of decision makers (DMs), subjective criteria and objective criteria in the decision-making process to make the decision results more reliable and reasonable. A numerical example and comparison are provided to illustrate the practicability and usefulness of the method. This study enriches the theory and methodology of blockchain technology and MAGDM analysis.
Ahmed Alzahrani, Ahmed Alenezi, Hany F. Atlam, Gary Wills
The healthcare data are considered as a highly valuable source of information that can improve healthcare systems to be more intelligent and improve the quality of the provided services. However, due to security and privacy issues, sharing data between healthcare organisations is challenging. This has led to data shortage in the healthcare sector which is considered as a significant issue not only in the Kingdom of Saudi Arabia (KSA) but also worldwide. The primary objective of conducting this paper is to investigate the various factors that enable secure sharing and exchange of healthcare information between different healthcare providers in the KSA. It starts by discussing the current literature and frameworks for managing healthcare data information and the challenges that health providers encounter, particularly when it comes to issues such as data security, patient privacy, and healthcare information exchange. These challenges in managing healthcare data have necessitated the nee d for implementing a solution that can allow medical providers to have access to updated healthcare information. Attention in the healthcare sector has been drawn to blockchain technology as a part of the solution, especially after the technology was successfully applied in the financial sector to improve the security of financial transactions, particularly involving digital currencies such as Bitcoin. Therefore, a framework based on the blockchain technology has been proposed to achieve the goals of the present research.
Ordinos is a novel verifiable tally-hiding e-voting system. At its heart, a homomorphic encryption scheme and secure multi-party computation (MPC) are used to tally votes and securely determine the voting result, without necessarily revealing the full tally (e.g., the number of votes per candidate)The proof of concept implementation of Ordinos is based on a threshold variant of the Paillier encryption scheme and two MPC protocols for the comparison of encrypted numbers (greater-than and equality). Due to the threshold construction, the decryption key is shared among a set of trustees. The MPC protocols for comparison require precomputed encrypted randomness of certain shape. Formerly, a trusted party was employed to generate the key shares and randomness and distribute them to the trustees. In this thesis, the trusted party was replaced by MPC protocols that allow to generate the key shares and randomness among the trustees. The protocols provide security against malicious parties in the honest-majority setting. The key generation follows a proposal by Nishide and Sakurai (2010) that is based on verifiable secret sharings and zero-knowledge proofs for committed values. We introduce a few adaptations to reduce its runtime using mostly standard techniques. The generation of randomness is based on the Paillier encryption scheme as an arithmetic black box and standard zero-knowledge proofs for Paillier encrypted values. The protocols were implemented and their performance was evaluated in a local network. Most notablythe implemented key generation protocol for threshold Paillier showed an expected average runtime around 95 minutes for generating 2048-bit keys among 3 trustees with a threshold of 2. Since existing implementations provide security only in the semi-honest setting, this is the first time that an approach with security against malicious parties was implemented and evaluated. Overall, the distributed generation of both key shares and randomness takes considerably more time compared to the use of a trusted party, but avoids security risks and trust problems that occur with trusted parties.
Open access
Internet Traffic Analysis and Secure E-voting
Advanced Steganography and Watermarking Techniques
The recent report on FinTech to the European Commission by the Expert Group on Regulatory Obstacles to Financial Innovation (ROFIEG), of which the author was a member, noted that just 19 of the 161 largest retail and commercial businesses globally are implementing digital transformation at scale. 3 However, over the next 10 years, Europe will grow its FinTech market with existing and new players deploying Al, DLT, smart contracts, and quantum computing at scale. Al will radically transform the front, middle, and back offices of banks. However, as I conclude elsewhere,' the industry will have to manage its information architectures better if it is to fully leverage the potential of an Al to take data analytics to the next level or reduce the burgeoning costs of regulatory compliance. Significantly, innovations in smart contracts and DLT will transform the payment marketplace as they will enable crypt° assets of all types to be traded at all levels across markets. I expect that disruptive digital innovations based on the trading of cryptoassets will transform monetary and fi nancial systems. However, quantum computing with its potential to make strong Al a reality, and at a practical level to perform complex tasks, such as optimizing investment portfolios, identifying arbitrage opportunities, performing accurate credit and risks scoring, and so on, will be the fi nal step in the digital transformation of the industry. It is clear from the forgoing that no one technology is a silver ballet in digital transformation of financial institutions.
Bitcoin market capitalization has recently surpassed $1 trillion. According to the popular belief one of the key characteristics of bitcoin is its excessive volatility. This paper provides evidence that high volatility of bitcoin is largely a misperception. We show that bitcoin return fluctuations are lower than those of roughly 900 different stocks in the S&P1500 and 190 stocks in the S&P500. Moreover, we find that bitcoin is less volatile than commodities such as oil and silver, US Treasuries, AAA-rated corporate bonds, EU carbon credits, and some of the most popular technology and media stocks: Apple, Twitter, and Netflix. Equally important, we find that during the March 2020 stock market crash triggered by COVID-19, bitcoin volatility was lower than most of the above-mentioned asset classes. Significant decline in bitcoin volatility over the last decade renders it more âinvestableâ by conservative investors.
Interplays between organizations and technologies are crucial to companiesâ sustainable success. Like two pivotal threads in a woven fabric, companies must tie and interlace both in their organizational design and decision-making (Zammuto et al. 2007). The research has looked into aspects of this interplay for several decades and has specifically acknowledged ITâs importance to foster competitive advantages (see e.g. Hickson et al. 1969; Mata et al. 1995). Companies now face the paradigm shift of digitalization, which offers extensive opportunities but also poses new challenges and threatens companiesâ existence (Sebastian et al. 2017). Thus, our assumptions, practices, and underlying concepts of IT in organizations are changing drastically (Baskerville et al. 2020). Emerging digital technologies such as cloud computing, mobile computing, extended reality, artificial intelligence, and distributed ledger technology require and enable business model innovations (Nambisan et al. 2017). Thus, the paradigm shift of digitalization is forcing companies to reconsider common practices for organizational design and decision-making to remain viable in times of such environmental turbulence (Pavlou and El Sawy 2010; Sambamurthy and Zmud 2000). As an effort to cope with digitalizationâs new requirements, companies often engage with digital transformation to reconfigure their deep structures, i.e. their prior choices on organizing and routines (Besson and Rowe 2012; Gersick 1991). However, digital transformation entails an entirely new organizational identity, requiring a profound understanding and appropriate responses to be successful (Wessel et al. 2020). In this thesis, I pursue the overarching research aim to elucidate the challenges and choices in organizational design and decision-making for companies engaging with digital transformation. Contributing to its overarching research aim, this thesis consists of six individual essays. These use digital transformation, organizational design, ambidexterity, and IT governance as their locus and primary theoretical lenses. Further, I structure the essays in three research fields, with corresponding research goals: First, I seek to conceptualize organizational change in the digital age. In this regard, Essay 1 identifies five perspectives on continuous change that foster a successful digital transformation and extend the literatureâs prior focus on episodic change models. Essay 2 unveils the changes to organizationsâ assumptions and practices in digital transformation as well as the distinct differences between organizing for IT and organizing for digital. Second, I seek to foster the understanding of ambidextrous IT organizationsâ design as a common organizational response to digital transformation. Thus, in Essay 3, I identify relevant design options for agile IT setups and seven salient archetypes of organizational design. In Essay 4, I address the challenges and IT governance mechanisms in ambidextrous IT organizations and posit five managerial paradoxes. Third, I seek to provide guidance for organizational decision-making for the management of digital technologies. In Essay 5, I provide a process framework to successfully manage client-provider relationships in cloud computing. In Essay 6, I transfer a risk quantification approach from the automotive industry to technology platforms in the Internet of Things so as to derive implications for security governance. Considering each essayâs distinct questions and approaches, this cumulative thesis follows a multi-methodological research approach to study different facets of organizational design and decision-making (Goldkuhl 2012; Kaplan and Duchon 1988; Mingers 2001). In sum, with this thesis, I provide a thorough and multifaceted investigation of digital transformation. Further, I contribute to the research, reflecting the associated challenges and guiding organizations toward appropriate responses (Yoo et al. 2012). Thus, I add to the discourse in IS research and organizational studies to extend our thinking and theorizing about companiesâ fabric of organization and technology. This stimulates further research to understand and successfully guide companiesâ digital transformation.
PaweĆ ĆniataĆa, M. Hadi Amini, Kianoosh G. Boroojeni
Information fusion has been a topic of immense interest owing to its applicability in various applications. This brings to the fore the need for a flexible and accurate fusion algorithm that can be versatile. The BrooksâIyengar algorithm is one such fusion algorithm. It has since its inception found numerous applications that deal with the fusion of data from multiple sources. The uniqueness of the BrooksâIyengar algorithm is the ease with which the data from multiple sensors in a local system can be fused and also reach consensus in a distributed system with the added capability of fault tolerance. Blockchain has found its use as a distributed ledger and has successfully supported and fueled many crypto-currencies over the years. Information fusion with regard to blockchains is a topic of great research interest in the past couple of years. Since blockchain has no official node, the introduction of a decentralized network and a consensus algorithm is required in making the interactions and exchanges between multiple suppliers easier and thus leads to business being carried out without any hassles. In this paper, we attempt to understand and describe the deployment of multiple sensors to measure various aspects of the physical world. We discuss a novel technique of employing the BrooksâIyengar algorithm in the design of the system that would decentralize the data source from the corresponding measurements and thus ensure the integrity of the transactions in the blockchain. Finally, a theoretical analysis of the performance of the algorithm when used in a blockchain based decentralized environment is also discussed.
Open access
Distributed systems and fault tolerance
Distributed Sensor Networks and Detection Algorithms
With the rapid development of the Internet of Things (IoT), more and more devices are connected to the Internet. As IoT devices are resource-constrained in terms of processing, storage and network capacity, it becomes a challenging task to ensure the access of IoT devices. Identity authentication is a key technology to prevent illegal users from access resources and permissions. Based on the principle of blockchain technology, combining blockchain technology with IoT, this paper proposes a blockchain system framework for IoT identity authentication, which implements the authentication between devices and cloud servers, IoT base stations as well as devices, and then analyzes its feasibility.
Blockchain's popularity has seen a historic rise over the last decade. However, existing blockchain systems have a major issue with scalability, which has become one of the main obstacles in technology's adoption in mainstream. There have been several attempts to address this limitation by identifying Blockchain's scalability/performance bottlenecks (e.g. those mainly related to consensus algorithms), and thus proposed different solutions (e.g., new consensus protocols) to address such limitations. Other works applied sharding to tackle the issue. All solutions however have mainly focused on Cryptocurrency applications, and thus addressing the scalability of blockchain systems for general applications remains a concern. This work proposes a scalable blockchain protocol for general applications (i.e., not restricted to Cryptocurrencies). To improve the two major factors affecting transaction scalability, namely throughput and latency, we needed to modify both the blockchain structure as well as the block generation process. ZyConChain, the proposed Blockchain system, introduces three types of blocks that form three separate chains: parentBlock, sideBlock and state block. These blocks are generated based on different consensus algorithms, as each algorithm has specific properties that make it suitable for each type of block. To improve the overall performance, ZyConChain generates sideBlocks (that carry transactions) at a high rate and keep them in a pool. To generate parentBlock, miners, instead of packing transactions into a block as they do in conventional blockchains, pack sideBlocks into a parentBlock. SideBlocks are generated based on an adapted Zyzzyva consensus protocol, with O(\log n) complexity. This has reduced the final consensus complexity per transaction, in comparison to previous work. To enable the protocol to scale out with the increase in the number of nodes, ZyConChain applied sharding technique. Parallel state chains have also been introduced to address cross-shard transactions.
In this note, we report several solutions to the STARK-Friendly Hash Challenge: a competition with the goal of finding collisions for several hash functions designed specifically for zero-knowledge proofs (ZKP) and multiparty computations (MPC). We managed to find collisions for 3 instances of 91-bit hash functions. The method used is the classic parallel collision search with distinguished points from van Oorshot and Wiener (1994). As this is a general attack on hash functions, it does not exhibit any particular weakness of the chosen hash functions. The crucial part is to optimize the implementations to make the attack cost realistic, and we describe several arithmetic tricks.
Đaryna Chyzhevska, Olga TYMOFEIEVA, Hanna Sydorenko-Melnyk
The aim of the article is to substantiate the integral approach to residential property building state policy implementation in the context of the power decentralization. The objectives in the article are achieved using the following research general and special methods: analysis and synthesis, systematization and generalization, dialectical approach, causation. The integrated approach to implement the state policy on residential property building at the expense of the population has been further developed. This approach is based on decentralization of the state regulation of residential property building industry. Structural and logical scheme of the existing system of residential property building industry state regulation at the expense of population was formed. This will allow the solution of the problems in the process of residential property building on spots in a fairly short time due to the efficient distribution of functions among the various branches of state power and their assigned responsibility. The stages of renewal of financing the process of residential property building under the principle of decentralization are presented in the work. The article substantiates that the application of an integral approach to implement the state policy of residential property building, based on the principle of power decentralization. It will allow the increase in the level of public confidence in the residential property building industry. Given the experience of solving the housing problem in different countries, we suggest to build the state housing policy in Ukraine, taking into account the specific opportunities available and financial instruments already existing.
Having recently celebrated its ten-year anniversary, Bitcoin should be considered a qualified success. In October 2020, each unit1 was worth about $10,700, and the entire market capitalization was approximately $200 billion.2 Bitcoin is a significant economic force with sizable market value. Despite this success, however, Bitcoin has not been widely adopted as a method of payment, which was its intended use.3 By providing a template for a durable cryptocurrency, Bitcoin also blazed a path for other cryptocurrency projects. In terms of market capitalization and current importance, Ethereum is comfortably in second place.4 In October 2020, it had a market capitalization of approximately $40 billion.5 Unlike Bitcoin, however, Ethereum was not designed primarily to serve as a method of payment. Ethereum supports a system of sophisticated âsmart contractsâ that would not work on the Bitcoin system. Smart contracts and cryptocurrencies have sparked considerable interest among legal scholars in recent years, and a growing body of scholarship focuses on whether smart contracts and cryptocurrencies can sidestep law and regulation altogether.6 Bitcoin is famously decentralized, without any central actor controlling the system. Its users remain largely anonymous, using alphanumeric addresses instead of legal names. Ethereum shares these traits and also supports smart contracts that can automate the transfer of the Ethereum cryptocurrency (known as ether). Ethereum also supports specialized âtokensâ that can be tied to the ownership of assets, goods, and services that exist completely outside of the Ethereum blockchain. The goal of this Article is to evaluate the degree to which cryptocurrencies and smart contracts can operate outside the reach of law and regulation. By some accounts, cryptocurrencies and smart contracts will revolutionize private law.7 Some argue they have the potential to displace contract and property law. For example, in a previous article, I argued that Bitcoin represents a system of private property that exists wholly outside of traditional legal structures.8 In this Article, I will argue that a complete revolution is not inexorable.9 Facing the technical and complicated nature of this subject, we should keep in mind a simple fact: cryptocurrencies and smart contracts are computer data and computer programs. To a large extent, they will have legal force only if given force by judges, regulators, and legislators. Part II describes Bitcoin and how it creates a system of property that exists outside of legal structures. Bitcoin is special because it controls no external assets (like securities, dollars, or gold). It is purely ânotionalâ property that exists only on a computer file. Part III describes Ethereum and how it builds upon the principles of Bitcoin. The primary innovation of Ethereum is smart contracts, which allow for variable and conditional transfers of cryptocurrency. To be of commercial value, however, smart contracts must incorporate economic or financial information (e.g., interest rates or exchange rates). Ethereum allows users to incorporate this information using third party âoracles.â While oracles allow for sophisticated transactions, their presence illustrates some of the limits of smart contracts. Part IV extends the discussion of Ethereum and explains how many developers use it as a way to effectuate property transactions. Tokens are specialized smart contracts used to represent ownership of assets or certain privileges. Conceivably, ownership in any assetâ homes, cars, etc.âcould be represented by Ethereum tokens. Rather than using a deed of transfer, owners could simply transfer the representative tokens. Part V develops what this Article calls a âremote-computer modelâ of Bitcoin and Ethereum. Because Bitcoin and Ethereum are computer programs and computer data, we can view each as constituting a single computer. This hypothetical computer is remote in the sense that judges, regulators, and legislators can exercise little control over it directly. The remote computer controls ownership of cryptocurrency units, leaving direct cryptocurrency transactions outside the scope of traditional legal institutions. That being said, smart contracts often purport to control external resources and rights. For example, a smart contract might purport to control the transfer of land or stock in a corporation. These transactions have effects outside the hypothetical remote computer and can potentially be subject to control by legal institutions.
The cryptocurrency market is represented by more than 6,099 different cryptocurrencies with a total market capitalization of USD 354,316 million with Bitcoin dominance over 60%. Despite the increasing amount of scientific research, a comprehensive analysis of factors influencing the price of cryptocurrency is still needed. Previous studies have focused on the Bitcoin capitalization changes, rather than relationships and dependencies between the price of different cryptocurrencies and other factors. The author proposed a multiple linear regression model, which can be used for the cryptocurrency price forecast. The author tested the hypothesis, that Bitcoin's closing price changes likely in response to changes in altcoin prices and Google search index as well. According to the conducted research, the price of Bitcoin depends significantly on Google's search index on the specific cryptocurrency name. The revealed multiple regression equation can be further used for creating operational analytical programs for forecasting the price movement of Bitcoin.