Edimara Mezzomo Luciano, Odirlei Antônio Magnagnagno, Rodrigo Couto de Souza, Guilherme Costa Wiedenhöft
The recent popularization of distributed ledger technologies, which is better known in the financial sector due to digital currencies, has led to the appearance of numerous applications developed for the blockchain environment. The goal of this research is to investigate how a blockchain can contribute to the reduction of the vulnerabilities to corruption in the Brazilian context. Two stages of a literature review have been performed. The first identified the vulnerabilities to corruption in the Brazilian context and the second one identified the effective uses of blockchain characteristics. Subsequently, a deductive analysis was performed, aiming to verify which of the Blockchain initiatives presented could be potentially applied in the fight against corruption. This study points out ways to mitigate fraud and other causes of corruption to help regain society's trust in state institutions in Brazil, which has been suffering over the years from corruption scandals. Additionally, a research agenda leading to anti-corruption studies has been discussed.
Duc V. Le, Lizzy Tengana Hurtado, Adil M. Ahmad, Mohsen Minaei · 6 authors
Abstract The Bitcoin network has offered a new way of securely performing financial transactions over the insecure network. Nevertheless, this ability comes with the cost of storing a large (distributed) ledger, which has become unsuitable for personal devices of any kind. Although the simplified payment verification (SPV) clients can address this storage issue, a Bitcoin SPV client has to rely on other Bitcoin nodes to obtain its transaction history and the current approaches offer no privacy guarantees to the SPV clients. This work presents T 3 , a trusted hardware-secured Bitcoin full client that supports efficient oblivious search/update for Bitcoin SPV clients without sacrificing the privacy of the clients. In this design, we leverage the trusted execution and attestation capabilities of a trusted execution environment (TEE) and the ability to hide access patterns of oblivious random access machine (ORAM) to protect SPV clients’ requests from potentially malicious nodes. The key novelty of T 3 lies in the optimizations introduced to conventional ORAM, tailored for expected SPV client usages. In particular, by making a natural assumption about the access patterns of SPV clients, we are able to propose a two-tree ORAM construction that overcomes the concurrency limitation associated with traditional ORAMs. We have implemented and tested our system using the current Bitcoin Unspent Transaction Output (UTXO) Set. Our experiment shows that T 3 is feasible to be deployed in practice while providing strong privacy and security guarantees to Bitcoin SPV clients.
The object of this research is the international standards AML/CFT (Anti-Money Laundering/Combating the Financing of Terrorism) for the sphere of virtual assets (cryptocurrencies) developed by FATF (Financial Action Task Force), and possibilities of their effective implementation into the national legislation. The author examines new revision of the Recommendation 15 and Glossary (of October 2018), explanatory note to new revision of the Recommendation 15, and implementation guidance of the risk-oriented approach towards virtual assets and service providers in the sphere of virtual assets (of June 2019); considers provisions of the Federal Law of July 31, 2020 No.259-FZ “On Digital Financial Assets, Digital Currency, and Amendments to Certain Legislative Acts of the Russian Federation” becoming effective in January 2021. Based on the analysis of most recent international and Russian acts on the questions of legal regulation of cryptocurrencies turnover, the need is underlined for introducing amendments to the Russian legislation with regards to exercising financial monitoring of transactions with cryptocurrencies in Russia. The author indicates certain fundamental aspects related to collection and validation of personally identifying information on the holders of cryptocurrency and tracing of their transactions.
We live in a time of space, also in the study of organization. This review essay reflects on the state and the potential of organization theory’s spatial turn by embedding it in a wider movement of thought in the humanities and social sciences. Reading exemplary studies of organizational spatialities alongside the broader history and renaissance of spatial thinking allows us to identify and discuss four twists to the spatial turn in organization theory. First, organization is understood as something placed or sited. Second, it is a site of spatial contestation, which is constitutive for (and not merely reflective of) organizational life. Third, such contestation is itself an outcome of a spatial multiplicity that encompasses affects, technologies, voids and absences. Fourth, such an excess of space is beyond (or rather before) representation and thus summons a spatial poetics. In following these twists, increasingly complex and speculative topographies of organization take shape.
Blockchain, as a promising solution to develop secure distributed ledgers, has drawn a huge attention over the last decade. By introducing a pseudonymous payment model with no central authority, blockchain marked the new generation of online payment systems, known as Cryptocurrencies. For most of the existing cryptocurrencies, scalability has become a challenging problem. When dealing with an ever increasing number of users, miners, and transactions, the technology is unable to scale and provide the same performance as centralised systems (e.g. centralised payment systems).Without addressing this fundamental scalability problem, such a promising technology may not be able to be adopted in mainstream. This paper provides an attempt to analyse the scalability of existing blockchain protocols and look at the major factors affecting scalability, namely throughput and latency. We also describe the HTNZ protocol, a new approach to improve the scalability of Satoshi Nakamoto's model [1], validated by experimental results. HTNZ introduces two new components, namely, sideBlock and helper. SideBlock has a slightly different structure of block and increases the number of transactions that can be processed per each interval.
A key communication technology in smart cities and smart buildings for automation is RFID. Proving the simultaneous presence of a group of RFID-tagged objects is a practical need in many application areas within this domain. Some examples of this include vehicle fleets, smart parking, safety in public places (smart cities), security and access control (smart buildings), and asset location (supply chain system, health care industry). Security, privacy, and efficiency are central issues when designing such a grouping-proof protocol. This work is motivated by Sundaresan et al.'s grouping-proof protocol, which applies zero-knowledge techniques. In this paper, we propose a lightweight, offline, serial-dependency grouping-proof protocol. Compared to existing grouping-proof protocols, our scheme improves on efficiency, scalability, security, and communication cost. It resists well-known attacks on grouping-proofs including tag/reader impersonation, tracking, replay, desynchronization, and message integrity.
Purpose: A burgeoning body of research has described how the blockchain technology may affect the way firms operate within the recording industry which has undergone profound changes due to the dematerialisation of music and the emergence of now consumption habits. The purpose of the paper is to explore both the challenges and the opportunities related to the application of smart contracts and blockchain mechanisms to the recording industry. Approach/Methodology/Design: Based on a review of contributions made to the literature in various fields, we discuss recent developments, relying on several examples and use cases which bring an updated perspective to a topical question. While the blockchain brings interesting solutions in favour of an improved management of copyright data and fees collection, several barriers impede their uptake and large-scale adoption. Findings: We argue that the absence of both technological and regulatory standards, the resistance to change, and the necessary use of cryptocurrency, are all obstacles to a profound transformation of the sector. Practical Implications: To overcome these limitations, we suggest three recommendations that deal with technological standards, cooperative agreements, and international regulation around blockchain. Originality/Value: So far, the literature tends to focus either on blockchain technology or on smart contracts when discussing technological evolution within the recording industry. In this paper, we bring together these two elements which are definitely complementory to each other. Further research efforts are required to investigate in more details the feasibility and relevance of the recommendations we make.
With the development of precise positioning technology, a growing number of location-based services (LBS) emerge. For example, visit a specific place to get the corresponding reward. This also leads to location fraud by illegal users in order to gain benefits. Thus, it is necessary to verify location certificates provided by users. However, present proof of location systems are deficient in verifying users’ location certificates while protecting users’ privacy. Users do not flexibly control their location certificates either. Based on blockchain, a kind of distributed proof of location system architecture was proposed and based on the proposed system architecture, a kind of proof of location protocol with zero-knowledge proof was proposed further. With the proposed architecture and the protocol, the proposed proof of location system allows users to freely select disclosed certificate parameters and positional accuracy according to their needs so that hierarchical location privacy protection was achieved.
Purpose: The paper explores the differences between countries concerning perception and use of traditional and virtual money. We try to answer the question who uses virtual money for investment and building assets and who uses it just for Internet payments. The background of the analysis are significant changes that have taken place in the virtual money market in recent years in relation to changes in the global financial market. Design/methodology/approach: A pilot study was conducted in Poland, the Russian Federation, and China, which is supposed to be an introduction to the bigger and wider survey. It was conducted within December 2019 and January 2020 with 81 surveyed persons. These were students of financial studies in the chosen countries. The paper questionnaire used in the survey consisted of 26 questions connected to virtual money plus 5 demographic questions. It was provided personally by teachers in class. Findings: The findings indicated that there are differences between countries in perception and the use of traditional and virtual money. These discrepancies can have cultural or historical background. Practical Implications: The practical usefulness of the whole study is that gathered information will permit to examine the economic and financial literacy of the respondents and their preferences for the use of innovative financial instruments. Originality/value: The study is related to the very current issue – virtual money as alternative to the currently functioning fiduciary money. The result of the research as one of the first indicated that a different perception of traditional and virtual money among different countries exist. This statement might be a huge contribution to the analysis of the current and further financial system.
This paper aims at identifying a validated risk model for the cryptocurrency market. We propose a stochastic volatility model with co-jumps in return and volatility (SVCJ) to highlight the role of jumps in returns and volatility in affecting Value-at-Risk (VaR) and Expected Shortfall (ES) in cryptocurrency market. Validation results based on backtesting show that SVCJ model is superior in terms of statistical accuracy of VaR and ES estimates, compared to alternative models such as TGARCH (Threshold GARCH) volatility and RiskMetrics models. The results imply that for the cryptocurrency market, the best performing model is a stochastic process that accounts for both jumps in returns and volatility.
Blockchain has become one of the core technologies in Industry 4.0. To help decision-makers establish action plans based on blockchain, it is an urgent task to analyze trends in blockchain technology. However, most of existing studies on blockchain trend analysis are based on effort demanding full-text investigation or traditional bibliometric methods whose study scope is limited to a frequency-based statistical analysis. Therefore, in this paper, we propose a new topic modeling method called Word2vec-based Latent Semantic Analysis (W2V-LSA), which is based on Word2vec and Spherical k-means clustering to better capture and represent the context of a corpus. We then used W2V-LSA to perform an annual trend analysis of blockchain research by country and time for 231 abstracts of blockchain-related papers published over the past five years. The performance of the proposed algorithm was compared to Probabilistic LSA, one of the common topic modeling techniques. The experimental results confirmed the usefulness of W2V-LSA in terms of the accuracy and diversity of topics by quantitative and qualitative evaluation. The proposed method can be a competitive alternative for better topic modeling to provide direction for future research in technology trend analysis and it is applicable to various expert systems related to text mining.
The novel coronavirus disease 19 (COVID-19) is rapidly spreading with a rising death toll and transmission rate reported in high income countries rather than in low income countries. The overburdened healthcare systems and poor disease surveillance systems in resource-limited settings may struggle to cope with this COVID-19 outbreak and this calls for a tailored strategic response for these settings. Here, we recommend a low cost blockchain and artificial intelligence-coupled self-testing and tracking systems for COVID-19 and other emerging infectious diseases. Prompt deployment and appropriate implementation of the proposed system have the potential to curb the transmissions of COVID-19 and the related mortalities, particularly in settings with poor access to laboratory infrastructure.
Andreas Penzkofer, Bartosz Kuśmierz, Angelo Capossele, William H. Sanders · 5 authors
In recent years several distributed ledger technologies based on directed acyclic graphs (DAGs) have appeared on the market. Similar to blockchain technologies, DAG-based systems aim to build an immutable ledger and are faced with security concerns regarding the irreversibility of the ledger state. However, due to their more complex nature and recent popularity, the study of adversarial actions has received little attention so far. In this paper we are concerned with a particular type of attack on the IOTA cryptocurrency, more specifically a Parasite Chain attack that attempts to revert the history stored in the DAG structure, also called the Tangle. \nIn order to improve the security of the Tangle, we present a detection mechanism for this type of attack. In this mechanism, we embrace the complexity of the DAG structure by sampling certain aspects of it, more particularly the distribution of the number of approvers. We initially describe models that predict the distribution that should be expected for a Tangle without any malicious actors. We then introduce metrics that compare this reference distribution with the measured distribution. Upon detection, measures can then be taken to render the attack unsuccessful. We show that due to a form of the Parasite Chain that is different from the main Tangle it is possible to detect certain types of malicious chains. We also show that although the attacker may change the structure of the Parasite Chain to avoid detection, this is done so at a significant cost since the attack is rendered less efficient.
Holger Kinkelin, Richard von Seck, Christoph Rudolf, Georg Carle
The security of cryptographic communication protocols that use X.509 certificates depends on the correctness of those certificates. This paper proposes a system that helps to ensure the correct operation of an X.509 certification authority and its registration authorities. We achieve this goal by enforcing a policy-defined, multi-party validation and authorization workflow of certificate signing requests. Besides, our system offers full accountability for this workflow for forensic purposes. As a foundation for our implementation, we leverage the distributed ledger and smart contract framework Hyperledger Fabric. Our implementation inherits the strong tamper-resistance of Fabric which strengthens the integrity of the computer processes that enforce the validation and authorization of the certificate signing request, and of the metadata collected during certificate issuance.
I P S P Wardhana, Gede Rasben Dantes, Kadek Yota Ernanda Aryanto
Abstract The falsification and embezzlement of personal data are still found in several cases in the past year. The reason is personal data in physical form are easily manipulated and difficult to be distinguished from the original. The most detrimental impact is if a person’s personal data is used for credit application fraud in the banking industry. Implementation of blockchain technologies, one of which is Ethereum, allows the use of contracts as a rule that must be fulfilled by the parties involved. All stored transactions are perpetual (cannot be deleted or changed), easy to be audited, transparent, and distributed at each participating node. This study aimed to develop a smart contract for personal data transactions with a case study of credit submission at the Bank. The authors developed a trial application using the prototype method in the process of assessment. Assessment was done by black box testing method in the scope of the lab with 10 credit submission data to be transacted. It is resulting in all credit submission data can be transacted and stored in the smart contract. The interview resulted in an opinion that blockchain technology can be used to store personal data and submit credit submissions at the Bank. The results of the analysis on assessments and interviews conclude that blockchain technology can be used as a medium to store personal data and secure credit applications. For future research, testing transactions can be done on Testnet networks with changing several blocks of data.
Muhammad Abubakr Naeem, Mudassar Hasan, Muhammad Arif, Syed Jawad Hussain Shahzad
We compare the hedging, safe-haven, and diversification potential of gold and Bitcoin for different investment styles and industry portfolios in the United States. We find that gold is at least a weak hedge for the style and industry portfolios except for utilities, energy, and telecom. The hedging potential of gold is comparatively higher for large-cap portfolios, whereas Bitcoin offers minimal hedging effectiveness. However, Bitcoin shows hedging potential for the noncyclical industries. Although investors need a higher amount of investment to hedge the downside risk using gold, it still is a superior hedging instrument compared with Bitcoin. Finally, the analysis using the conditional diversification approach shows that gold is a superior and stable diversifier for style and industry portfolios. Overall, our findings provide evidence of superior safe-haven and hedging potential of gold over Bitcoin.
Ahmed Taha, Ahmed Zakaria, Dong‐Seong Kim, Neeraj Suri
Cloud computing offers a model where resources (storage, applications, etc.) are abstracted and provided “as-a- service” in a remotely accessible manner. Although there are numerous claimed benefits of the Cloud to ensure confidentiality, integrity, and availability of the stored data, the number of security breaches is still on the rise. The lack of security assurance and transparency prevented customers/enterprises from trusting the Cloud Service Providers (CSPs). Unless the customer’s security requirements are identified and documented by the CSPs, customers can not be assured that the CSPs will satisfy their requirements. Furthermore, the customer’s compensation upon a violation is a manual time intensive process. In this paper we address the aforementioned challenges by proposing a decentralized customer-based monitoring approach running over Ethereum blockchain. The proposed approach allows the customer(s) to validate the compliance of CSP(s) to the contracted services in the Service Level Agreements (SLAs) and “autonomsly” compensate customers in case of security breaches. At the same time, the proposed approach prevents customers from misreporting for financial gain. The approach builds upon the Ethereum blockchain infrastructure in order to securely store monitoring logs and incorporate SLAs as smart contracts. The compliance validation framework is implemented and its functionality is evaluated on Amazon EC2 and Ethereum Blockchain.
The paper bill of lading remains pervasive despite numerous problems associated with its form. Blockchain heralds change as it allows unique tokens to be possessed and traded peer-to-peer instantaneously over the internet without the need for a trusted central administrator. Blockchain furthermore promises to ease processes thanks to its applicability in smart contracting procedures. The Model Law on Electronic Transferable Records (MLETR), passed by UNCITRAL in 2017, provides the relevant legal framework for legal protection of the blockchain bill of lading. This paper proposes Ethereum as a viable smart contract-enabled blockchain platform for a bill of lading system and examines said system’s compatibility with the MLETR. The analysis also shows that blockchain technology may have significant consequences for the ‘control’ approach for establishing possession of an electronic transferable record.
In this paper we propose a deep recurrent architecture for the probabilistic modelling of high-frequency market prices, important for the risk management of automated trading systems. Our proposed architecture incorporates probabilistic mixture models into deep recurrent neural networks. The resulting deep mixture models simultaneously address several practical challenges important in the development of automated high-frequency trading strategies that were previously neglected in the literature: 1) probabilistic forecasting of the price movements; 2) single objective prediction of both the direction and size of the price movements. We train our models on high-frequency Bitcoin market data and evaluate them against benchmark models obtained from the literature. We show that our model outperforms the benchmark models in both a metric-based test and in a simulated trading scenario
Bitcoin being a safe-haven asset is one of the traditional stories in the cryptocurrency community. However, during its existence and relevant presence, i.e., approximately since 2013, there has been no severe situation on the financial markets globally to prove or disprove this story until the COVID-19 pandemic. We study the quantile correlations of Bitcoin and two benchmarks—the S&P 500 and VIX—and make comparison with gold as the traditional safe-haven asset. The Bitcoin safe haven story is shown and discussed to be unsubstantiated and far-fetched, while gold comes out as a clear winner in this contest even when a broader cryptocurrency index (CRIX) is considered.
In this paper we propose a deep recurrent model based on the order flow for the stationary modelling of the high-frequency directional prices movements. The order flow is the microsecond stream of orders arriving at the exchange, driving the formation of prices seen on the price chart of a stock or currency. To test the stationarity of our proposed model we train our model on data before the 2017 Bitcoin bubble period and test our model during and after the bubble. We show that without any retraining, the proposed model is temporally stable even as Bitcoin trading shifts into an extremely volatile "bubble trouble" period. The significance of the result is shown by benchmarking against existing state-of-the-art models in the literature for modelling price formation using deep learning.
Blockchain and other forms of Distributed Ledger Technology (DLT) provide an opportunity to integrate digital information, management, and contracts to increase trust and collaboration within the construction industry. DLT enables direct peer-to-peer transactions of value across a distributed network by providing an immutable and transparent record of these transactions. Furthermore, there is potential for business process optimization and automation on the transaction level through the use of smart contracts, which are code protocols deployed on supported DLT systems. However, DLT research in the construction industry remains at a theoretical level; there have been few implementation case studies to date. One potential reason for this is a knowledge gap between use-case ideas and the DLT technical system implementation. This paper aims to reduce this gap by (1) reviewing and categorizing proposed DLT use cases in construction literature, (2) providing an overview of DLT and its design options, (3) proposing an integrated framework to match DLT design options with desired characteristics of a use case, and (4) analysing the use cases using the new framework. Together, the use case categories and proposed decision framework can guide future implementers toward more connected and structured thinking between the technological properties of DLT and use cases in construction.
Blockchain is a developing innovation that can possibly reform the worldwide business and make a confided in relationship in a multi-party business organize. Square chain is one of the steadiest open records that jelly exchange data, and is hard to produce. Since, the data put away in square chain is not identified with by and by recognizable data, it has the attributes of namelessness. There are various reasonable use situations where blockchain has been applied. All through the instructive course, students get different sort of execution certificates, score transcripts, marksheets and so on which can turn into a critical ascribe for having admissions to new schools or new works. Because of hostile to manufacture mechanism, its simple to make fraud documents. So, as to take care of the issue of falsifying testaments, the advanced authentication framework dependent on blockchain innovation would be proposed. By the unmodifiable property of blockchain, the computerized authentication with hostile to fake and unquestionable status could be made. Through the unmodifiable properties of the blockchain, the framework not just improves the believability of different paper-based endorsements, yet additionally electronically decreases the misfortune dangers of different sorts of authentications.