Indonesia's recent development in legal policy toward cryptocurrency is pertinent to ask whether this new investment market has any more risk to throw over Indonesia than how to protect the existing variable parties by overall structural formation. This tendency has prevented the government to implement the machinery of more fundamental keynote of policy. Against this backdrops, this research first analyzes the existing laws and regulations to examine the current legal status of virtual currency in Indonesia with the method of conceptual analysis. Despite the Government's skeptical stance about economic soundness that cryptocurrency market leads, however, how to protect the various parties in the existing market is a different issue which still needs an urgent attention from policy makers, legal practitioners, judiciary and academic researchers. Therefore, this paper further studies the relevant laws and regulations governing the actual operation of cryptocurrency exchange in Indonesia to discuss the more practical aspects by interviewing an Indonesian cryptocurrency exchange and professional lawyers at Dentons HPRP. Subsequently, the most worrisome legal risks in the industry are diagnosed by interviewing a global cryptocurrency exchanges. This study concludes that BAPPEBTI Regulation No. 5 of 2019 cannot be the good answer to minimize the risk and will only harm bona fide market participants without a good-standing authority.
The Lightning Network is the most widely used payment channel network (PCN) to date, making it an attractive attack surface for adversaries. In this paper, we analyze the Lightning Network's PCN topology and investigate its resilience towards random failures and targeted attacks. In particular, we introduce the notions of channel exhaustion and node isolation attacks and show that the Lightning Network is susceptible to these attacks. In a preliminary analysis, we confirm that the Lightning Network can be classified as a small-world and scale-free network. Based on these findings, we develop a series of strategies for targeted attacks and introduce metrics that allow us to quantify the adversary's advantage. Our results indicate that an attacker who is able to remove a certain number of nodes should follow a centrality-based strategy, while a resource-limited attacker who aims for high efficiency should employ a highest ranked minimum cut strategy.
Isra Mohamed Ali, Maurantonio Caprolu, Roberto Di Pietro
Cryptographic algorithms have been used not only to create robust ciphertexts but also to generate cryptograms that, contrary to the classic goal of cryptography, are meant to be broken. These cryptograms, generally called puzzles, require the use of a certain amount of resources to be solved, hence introducing a cost that is often regarded as a time delay---though it could involve other metrics as well, such as bandwidth. These powerful features have made puzzles the core of many security protocols, acquiring increasing importance in the IT security landscape. The concept of a puzzle has subsequently been extended to other types of schemes that do not use cryptographic functions, such as CAPTCHAs, which are used to discriminate humans from machines. Overall, puzzles have experienced a renewed interest with the advent of Bitcoin, which uses a CPU-intensive puzzle as proof of work. In this paper, we provide a comprehensive study of the most important puzzle construction schemes available in the literature, categorizing them according to several attributes, such as resource type, verification type, and applications. We have redefined the term puzzle by collecting and integrating the scattered notions used in different works, to cover all the existing applications. Moreover, we provide an overview of the possible applications, identifying key requirements and different design approaches. Finally, we highlight the features and limitations of each approach, providing a useful guide for the future development of new puzzle schemes.
Миколаївський національний аграрний університет, Н. В. Лагодієнко, Ю. В. Волосюк, Миколаївський національний аграрний університет · 8 authors
Introduction. The paper examines and generalizes approaches to taxing cryptocurrencies in different countries of the world with the aim of identifying the most successful experience for its subsequent adaptation and application in the Ukrainian Legislation. The tendencies of the possible change of the cryptocurrencies control vector are revealed. The definitions of cryptocurrency are analyzed, possible variants of their legal status are determined. The analysis of prospects for establishing the legal status of cryptocurrencies in Ukraine is carried out. The draft laws on amendments to the Tax Code of Ukraine were studied. It was established that in Ukraine there was not yet formed the legal framework for determining the legal status and regulation of cryptocurrencies and proposed ways to improve Ukrainian legislation in the sphere of cryptocurrency transactions. \n \nPurpose. The purpose of the study is to analyze the global experience of cryptocurrency taxation in order to identify the best approaches to this problem in Ukraine. \n \nResults. Today, it is impossible to develop a universal mechanism for taxation of cryptocurrencies, since there are no single standards for the taxation of digital coins in the world. This is due to the fact that some countries do not want to recognize the use of digital money as legitimate, and countries that have given official status for cryptocurrencies use of their own approaches to taxation. The procedure for taxation of transactions using cryptocurrencies is governed by the national legislation of the member states. In this case, as a rule, the digital currency is treated as a commodity or an intangible asset, and not as a currency or money. \n \nConclusions. It has been proved that in the world practice several approaches to determining the legal status and taxation of cryptocurrencies with common trends have been formed. To date, Ukraine has not yet set up a legislative framework for the regulation of cryptocurrency, but there is a development of provisions and bills that need to be further elaborated.
Produzierende Unternehmen stehen unter großem Veränderungsdruck, der durch wachsende Produktkomplexität, steigende Kundenanforderungen und digitale Geschäftsmodelle induziert wird. Vorherrschende Trends wie Industrie 4.0 und Digitalisierung müssen genutzt werden, um nicht nur die Produktion effizienter zu gestalten, sondern auch innovative Geschäftsmodelle zu entwickeln. Diese gewährleisten, dass Unternehmen neue Märkte erschließen und neue Kunden gewinnen. Die von Unternehmen in der Vergangenheit fokussierten produktzentrierten Geschäftsmodelle werden durch die Digitalisierung in nutzerzentrierte Geschäftsmodelle transformiert. Zudem ist gerade eine Veränderung im Verhalten der Kunden zu beobachten, die sich zunehmend gezielt für Produkte mit höherem Leistungsumfang in Bezug auf digitale Fähigkeiten entscheiden, sodass sich die Digitalisierung ebenfalls in den Produkten wiederfindet. Dauerhafte Wettbewerbsfähigkeit bedarf folglich erweiterter digitaler Leistungen in Produkten.
Національний університет біоресурсів і природокористування України, О. О. Лемішко
Introduction. The urgency of budget support for reproductive processes in the agrarian sector of the Ukrainian economy is determined by its important role in ensuring the country’s food security, the formation of the agrarian market, the application of measures of customs and tariff regulation. \n \nPurpose. The purpose of the study is to determine the patterns of dynamics and structural development of indicators of budget support of reproductive processes in the agrarian sector of the Ukrainian economy. \n \nResults. According to the results of the analysis of the dynamics of expenditures of the State Budget of Ukraine for the agrarian sector of the economy for the years 2012-2019 it has been established that it is reliably described by a parabola with branches upwards and minimum values in 2015. And the actual data for 2012-2016 are formalized by a linear killing function with a minimum value at the end of the period. Comparison of the above results allows us to put forward the hypothesis that the point of bifurcation is connected with the signing by Ukraine of the Association Agreement with the EU, which strengthened the competitive position of the agrarian sector in comparison with other sectors of the national economy. As a result, the mentioned agriculture became more attractive for budget financing and investment in categories of absolute sizes, but its share in expenditures of the State Budget of Ukraine remains negligible. The patterns of the structural development of sources of budget financing of the agrarian sector of the economy, which are connected with the processes of budget decentralization, which are reflected in the growth of the share of local budgets in the Consolidated Budget of Ukraine, are revealed. Characteristic features of the expenditures of the State Budget of Ukraine to finance the agrarian sector of Ukraine are priority financial support for livestock, plant growing, hop growing, land reform, scientific activities, and Agrarian Fund activity. \n \nConclusions. Recommendations for improving the state financial policy of reproduction of capital in the agrarian sector of the economy are an increase in the absolute volume and specific weight in the total expenditures of the State Budget of Ukraine; structural changes in favor of the development budget; the transition to the formation of the budget for development on a medium-term basis; specification of expenditures according to the departmental and program classification at the level of state target programs, which will create preconditions for conducting a state audit of the effectiveness of their use.
Capable of aggregating multiple energy resources, the energy service company (ESCO) has been regarded as a promising alternative for improving power system flexibility and facilitate the consumption of renewable resources in the energy market. However, the issues have become significantly more serious related to the privacy and security of the data in consumption and trading. In this paper, we address the problem by proposing a privacy-preserving energy scheduling (PPES) model based on energy blockchain network. A Lagrangian relaxation method is applied to decompose the model into several individual optimal scheduling problems, and the individual scheduling problems are solved by consensus algorithm and smart contracts in energy blockchain network. The performance of the proposed model and method is evaluated with several case studies based on multiple energy nodes. Simulation results show the rationality and validity of the proposed method, and the model is conducive to the protection of environment and transparent scheduling of energy service companies (ESCOs). In addition, it can reflect the information of energy demand and supply to improve the privacy and security of data.
This paper introduces a scalable and secure contract-enforcement mechanism, called Cop, which can be applied to a broad range of multi-agent systems including small and large systems, time-critical systems, and systems-of-systems. Cop enforces contracts (or protocols) via the existing Law- Governed Interaction (LGI) mechanism, coupled with a new protective layer that significantly enhances the dependability and security of such enforcement. Cop is arguably superior to the currently popular blockchain-based smart-contract mechanisms, due to its scalability, interoperability, and the breadth of the spectrum of its domain of applications.
The recent rapid development of artificial intelligence (AI, mainly driven by machine learning research, especially deep learning) has achieved phenomenal success in various applications. However, to further apply AI technologies in real-world context, several significant issues regarding the AI ecosystem should be addressed. We identify the main issues as data privacy, ownership, and exchange, which are difficult to be solved with the current centralized paradigm of machine learning training methodology. As a result, we propose a novel model training paradigm based on blockchain, named Galaxy Learning, which aims to train a model with distributed data and to reserve the data ownership for their owners. In this new paradigm, encrypted models are moved around instead, and are federated once trained. Model training, as well as the communication, is achieved with blockchain and its smart contracts. Pricing of training data is determined by its contribution, and therefore it is not about the exchange of data ownership. In this position paper, we describe the motivation, paradigm, design, and challenges as well as opportunities of Galaxy Learning.
Searching for available parking spaces is a major problem for drivers especially in big crowded cities, causing traffic congestion and air pollution, and wasting drivers' time. Smart parking systems are a novel solution to enable drivers to have real-time parking information for pre-booking. However, current smart parking requires drivers to disclose their private information, such as desired destinations. Moreover, the existing schemes are centralized and vulnerable to the bottleneck of the single point of failure and data breaches. In this paper, we propose a distributed privacy-preserving smart parking system using blockchain. A consortium blockchain created by different parking lot owners to ensure security, transparency, and availability is proposed to store their parking offers on the blockchain. To preserve drivers' location privacy, we adopt a private information retrieval (PIR) technique to enable drivers to retrieve parking offers from blockchain nodes privately, without revealing which parking offers are retrieved. Furthermore, a short randomizable signature is used to enable drivers to reserve available parking slots in an anonymous manner. Besides, we introduce an anonymous payment system that cannot link drivers' to specific parking locations. Finally, our performance evaluations demonstrate that the proposed scheme can preserve drivers' privacy with low communication and computation overhead.
Nathalie Brender, Marion Gauthier, Jean‐Henry Morin, Arbër Salihi
In today’s debate on the potential disruptive effects of blockchain, audit and control professions are rarely in the spotlight although applications such as smart contracts and distributed ledgers could significantly impact them. We conducted a study based on the grounded theory to understand how auditors in Switzerland anticipate the impacts of blockchain on their activities. Based on our findings, three hypotheses have emerged. First, the potential effect of blockchain on the profession is not fully anticipated. Second, the profession will go through a paradigm shift in two ways: become more IT oriented and forward looking. Finally, the profile of the auditors will change.
Edge computing is a distributed computing paradigm that relies on computational resources of end devices in a network to bring benefits such as low bandwidth utilization, responsiveness, scalability and privacy preservation. Applications range from large scale sensor networks to IoT, and concern multiple domains (agriculture, supply chain, medicine. . . ). However, resource usage optimization, a challenge due to the limited capacity of edge devices, is typically handled in a centralized way, which remains an important limitation. In this paper, we propose a decentralized approach that relies on a combination of blockchain and consensus algorithm to monitor network resources and if necessary, migrate applications at run-time. We integrate our solution into an application container platform, thus providing an edge architecture capable of general purpose computation. We validate and evaluate our solution with a proof-of-concept implementation in a national cultural heritage building.
About 1Bn people around the globe are born and live without identity documents. In addition, displaced people, projected at 1Bn within a generation, often find themselves without worthy identity documentation even if they had any in their country of origin.
Given that centralized, top-down identity-granting solutions are failing a large portion of the world population, a bottom-up, grassroots, decentralized solution that allows every human being to create and own a trustworthy \emph{genuine global identity} is an urgent necessity. Such a bottom-up solution is worthy only if it is resilient to malicious antagonists that create fake and duplicate identities (so called \emph{sybils}). Furthermore, for a solution to be truly grassroots, the people that rely on it for their global identity should also be its sovereign. Hence its governance has to be sybil-resilient as well.
Here, we present a foundation for a decentralized, grassroots, bottom-up, self-sovereign process in which every human being may easily create and own a genuine global identity, realized as a public key. The solution relies on the formation of a Web of Trust among global identities, but does not rely on biometrics, nor does it require to store any personal information on public or even third-party storage, except for the public key itself. The approach is designed for natural realization using distributed ledger/blockchain technology. For the solution to be complete, additional components are needed, including a mechanism that encourages honest behavior and an egalitarian cryptocurrency to fuel the mechanism. These are a subject for future research.
While most of humanity is suddenly on the net, the value of this singularity is hampered by the lack of credible digital identities: Social networking, person-to-person transactions, democratic conduct, cooperation and philanthropy are all hampered by the profound presence of fake identities, as illustrated by Facebook's removal of 5.4Bn fake accounts since the beginning of 2019. Here, we introduce the fundamental notion of a \emph{genuine personal identifier}---a globally unique and singular identifier of a person---and present a foundation for a decentralized, grassroots, bottom-up process in which every human being may create, own, and protect the privacy of a genuine personal identifier. The solution employs mutual sureties among owners of personal identifiers, resulting in a mutual-surety graph reminiscent of a web-of-trust. Importantly, this approach is designed for a distributed realization, possibly using distributed ledger technology, and does not depend on the use or storage of biometric properties. For the solution to be complete, additional components are needed, notably a mechanism that encourages honest behavior and a sybil-resilient governance system.
Apr 20, 2019·MaxEnt 2019 - Proceedings of the 39th International Workshop on Bayesian Inference and Maximum Entropy Methods in Science and Engineering, Garching, Germany, 30 June - 5 July 2019
Randomization is an integral part of well-designed statistical trials, and is also a required procedure in legal systems. Implementation of honest, unbiased, understandable, secure, traceable, auditable and collusion resistant randomization procedures is a mater of great legal, social and political importance. Given the juridical and social importance of randomization, it is important to develop procedures in full compliance with the following desiderata: (a) Statistical soundness and computational efficiency; (b) Procedural, cryptographical and computational security; (c) Complete auditability and traceability; (d) Any attempt by participating parties or coalitions to spuriously influence the procedure should be either unsuccessful or be detected; (e) Open-source programming; (f) Multiple hardware platform and operating system implementation; (g) User friendliness and transparency; (h) Flexibility and adaptability for the needs and requirements of multiple application areas (like, for example, clinical trials, selection of jury or judges in legal proceedings, and draft lotteries). This paper presents a simple and easy to implement randomization protocol that assures, in a formal mathematical setting, full compliance to the aforementioned desiderata for randomization procedures.
This study examines whether the market efficiencies of major cryptocurrencies (e.g., Bitcoin, Ethereum, and Ripple) change over time based on the adaptive market hypothesis (AMH) of Lo (2004). In particular, we measure the degree of market efficiency using Ito et al.'s (2014, 2016, 2017) generalized least squares-based time-varying model. The empirical results show that (1) the degree of market efficiency varies with time in cryptocurrency markets, (2) the market efficiency level of Bitcoin is higher than that of the other markets over most periods, and (3) the market efficiency of cryptocurrencies has evolved. We conclude that the results support the AMH for the established cryptocurrency market.
Md. Nazmus Saadat, Syed Abdul Halim, Husna Osman, Rasheed Mohammad Nassr · 5 authors
<p class="Abstract"><span>Initially, blockchain is only used as a foundation of cryptocurrency, but today, we can see the rise of this new emerging technology are being implemented in many industries. In the future, most technologies around the world are expected to use blockchain as an efficient way to make online transactions. One of the areas that blockchain technologies can be applied is crowdfunding platforms. The most common problem with current crowdfunding scene in around the world including is that the campaigns are not regulated and some of the crowd-funding campaign turned out to be fraud. Besides, the completion of some projects also was significantly delayed. This project aims to solve these problems by applying Ethereum smart contracts to the crowdfunding site to that the contracts will be fully automatically executed, thus preventing frauds and ensuring that the projects can be delivered within duration given.</span></p>
This study examines whether the efficiency of cryptocurrency markets (Bitcoin and Ethereum) evolve over time based on Lo's (2004) adaptive market hypothesis (AMH). In particular, we measure the degree of market efficiency using a generalized least squares-based time-varying model that does not depend on sample size, unlike previous studies that used conventional methods. The empirical results show that (1) the degree of market efficiency varies with time in the markets, (2) Bitcoin's market efficiency level is higher than that of Ethereum over most periods, and (3) a market with high market liquidity has been evolving. We conclude that the results support the AMH for the most established cryptocurrency market.
Martin Florian, Sophie Beaucamp, Sebastian Henningsen, Björn Scheuermann
It is a common narrative that blockchains are immutable and so it is technically impossible to erase data stored on them. For legal and ethical reasons, however, individuals and organizations might be compelled to erase locally stored data, be it encoded on a blockchain or not. The common assumption for blockchain networks like Bitcoin is that forcing nodes to erase data contained on the blockchain is equal to permanently restricting them from participating in the system in a full-node role. Challenging this belief, in this paper, we propose and demonstrate a pragmatic approach towards functionality-preserving local erasure (FPLE). FPLE enables full nodes to erase infringing or undesirable data while continuing to store and validate most of the blockchain. We describe a general FPLE approach for UTXO-based (i.e., Bitcoin-like) cryptocurrencies and present a lightweight proof-of-concept tool for safely erasing transaction data from the local storage of Bitcoin Core nodes. Erasing nodes continue to operate in tune with the network even when erased transaction outputs become relevant for validating subsequent blocks. Using only our basic proof-of-concept implementation, we are already able to safely comply with a significantly larger range of erasure requests than, to the best of our knowledge, any other full node operator so far.
on behalf of the Neonatal Transport Study Group of the Italian Society of Neonatology (SIN), Maurizio Gente, Roberto Aufieri, Massimo Agosti · 8 authors
BACKGROUND: Despite regionalization of perinatal care provides for the "in utero" transfer of high-risk pregnancies, there will always be a number of neonates who undergo acute inter-facility transport. The presence of a well-organized Neonatal Emergency Transport Service (NETS) can prevent and reduce risks of transportation, especially for very preterm infants, and is therefore mandatory for any program of regionalization of perinatal care. Italian National Health System is highly decentralized and Regions are autonomous to structure, plan and delivery their regional health services. Consequently, organization models and resources available vary widely and significant regional differences in access and quality of health services have been reported in the past years. A national survey was conducted in 2015 by the neonatal transport study group of the Italian Society of Neonatology with the aim to describe neonatal transfer practices and to assess the Neonatal Emergency Transport Services (NETS) status in the 20 Italian regions. METHODS: A questionnaire regarding neonatal transfer practices and NETS activity for the previous year (2014) was sent to the 44 NETS operating in the 20 Italian regions. Demographic data were obtained from the Italian National Statistical Institute (ISTAT). RESULTS: The overall survey response rate was 100%. In 2014, only 12 (60%) of the 20 Italian regions were fully covered by NETS, 3 (15%) regions were partially covered, while neonatal transport was not available in 5 (25%) regions. Overall, in 2014, the 44 NETS operating in Italy transported a total of 6387 infants, including 522 (8.17%) having a gestational age < 28 weeks. CONCLUSIONS: The organization of NETS in Italy is devolved on a regional basis, resulting in a large heterogeneity of access and quality to services across the country. Where available, NETS are generally well-equipped and organized but limited volume of activities often cannot guarantee adequate levels of skills of personnel or an appropriate cost-efficiency ratio. The regions reported with lack of NETS have managed, or are trying, to fill the gap, but continuing efforts to reduce regional differences in the availability and quality of services are still needed.
This study conducts a systematic survey on whether the pricing behavior of cryptocurrencies is predictable. Thus, the Efficient Market Hypothesis is rejected and speculation is feasible via trading. We center interest on the Rescaled Range (R/S) and Detrended Fluctuation Analysis (DFA) as well as other relevant methodologies of testing long memory in returns and volatility. It is found that the majority of academic papers provides evidence for inefficiency of Bitcoin and other digital currencies of primary importance. Nevertheless, large steps towards efficiency in cryptocurrencies have been traced during the last years. This can lead to less profitable trading strategies for speculators.
The Internet of Things (IoT) is very attractive because of its promises. However, it brings many challenges, mainly issues about privacy preservation and lightweight cryptography. Many schemes have been designed so far but none of them simultaneously takes into account these aspects. In this paper, we propose an efficient attribute-based credential scheme for IoT devices. We use elliptic curve cryptography without pairing, blind signing, and zero-knowledge proof. Our scheme supports block signing, selective disclosure, and randomization. It provides data minimization and transaction unlinkability. Our construction is efficient since smaller key size can be used, and computing time can be reduced. As a result, it is a suitable solution for IoT devices characterized by three major constraints, namely low-energy power, small storage capacity, and low computing power.
Truxen is a Trusted Computing enhanced blockchain that uses Proof of Integrity protocol as the consensus. Proof of Integrity protocol is derived from Trusted Computing and associated Remote Attestations, that can be used to vouch a node's identity and integrity to all of the other nodes in the blockchain network. In this paper we describe how Trusted Computing and Proof of Integrity can be used to enhance blockchain in the areas of mining block, executing transaction and smart contract, protecting sensitive data. Truxen presents a Single Execution Model, that can verify and execute transaction and smart contract in a solo node, consequently enables remote calls to off-chain applications and performs in-deterministic tasks.