Neoliberalism propels a retreat from state supports for the population and the unfettering of privatization and profit seeking. The collapse of the Soviet Union was believed by many to be proof that Western democracy and capitalist markets had not only conquered the world, but were amongst the greatest achievements of humanity. While neoliberalism has shifted the state’s stake in the welfare of the population, the state remains important in determining and legitimating the rights of individuals and corporations to pursue a vulturine profit maximizing agenda. The disassembling effects of the gap between political inclusion and social exclusion are particularly evident in urban spaces where health and mortality rates, grocery and school options, and foreclosure signs often differ dramatically across city neighborhoods. A further effect of private profits becoming the primary benchmark for public urban projects is that there are neighborhoods in the city where profits are secured not through investment, but from disinvestment.
Blockchain technology enables the execution of collaborative business processes involving mutually untrusted parties. Existing platforms allow such processes to be modeled using high-level notations and compiled into smart contracts that can be deployed on blockchain platforms. However, these platforms brush aside the question of who is allowed to execute which tasks in the process, either by deferring the question altogether or by adopting a static approach where all actors are bound to roles upon process instantiation. Yet, a key advantage of blockchains is their ability to support dynamic sets of actors. This paper presents a model for dynamic binding of actors to roles in collaborative processes and an associated binding policy specification language. The proposed language is endowed with a Petri net semantics, thus enabling policy consistency verification. The paper also outlines an approach to compile policy specifications into smart contracts for enforcement. An experimental evaluation shows that the cost of policy enforcement increases linearly with the number of roles and constraints.
Thomas Buocz, Tina Ehrke-Rabel, Elisabeth Hödl, Iris Eisenberger
This article uses the example of the cryptocurrency Bitcoin and the General Data Protection Regulation (GDPR) to show how distributed networks challenge existing legal mechanisms of allocating responsibility. The Bitcoin network stores personal data by automated means. Furthermore, full nodes qualify as establishments and the network offers a service to citizens in the EU. The data processing within the Bitcoin network therefore falls into the material and territorial scope of the GDPR. To protect data subjects, the GDPR allocates responsibility to the controller, who determines the ‘how’ and the ‘why’ of the data processing. However, the distributed structure of the Bitcoin network blurs the lines between actors who are responsible and actors who are worth protecting. Neither the Bitcoin users running lightweight nodes or full nodes nor the miners determine the ‘how’ and the ‘why’ of the data processing. They carry out their network activities according to the Bitcoin protocol, which can only be adopted and enforced by a collective of full nodes and miners. Members of this collective are joint controllers under Article 26 GDPR, which obliges them to clearly and transparently determine their respective responsibilities for compliance with the GDPR. However, this mechanism fails because of the very structure it aims to eliminate. Therefore, a solution to allocating responsibility for data protection in distributed networks lies outside the GDPR.
Puwei Wang, Ji M, Jinchuan Chen, Tao Liu · 7 authors
Smart contracts (SCs) run on the distributed ledger technology (DLT) platform and can implement agreements between participants without a trusted third party. This paper uses the DLT and SC techniques to build distributed applications composed of existing services. In practice, there are many functionally-equivalent services on the Internet. To beat their competitors, the service providers usually offer flexible QoS and use dynamic pricing strategies. Moreover, the service providers can change at runtime, e.g., they may encounter problems so that their QoS drops suddenly. This makes achieving the optimization goal at runtime (e.g., the maximization of the utility) more difficult. To address this problem, first, this paper proposes an SC-based negotiation framework. The SCs can ensure that the transactions are automatically and reliably performed as agreed upon between the service requesters and providers. The DLTs can provide the reliable data of the requests and responses of the service requesters and providers to the SCs. In addition, the SCs can identify the troubled service providers, and find other service providers to replace them at runtime. Second, this paper proposes a Bayesian Nash equilibrium (BNE) of the service providers. In the BNE, the cost-efficient service providers offer the high QoS the service requester asks for and report their costs truthfully. This BNE enables the selection of the cost-efficient service providers and the achievement of the (near) maximization of the service requesters' utility. This paper implements the proposed negotiation framework on a DLT platform called Hyperledger Fabric. The experiment results demonstrate that the proposed approach outperforms the existing approaches and can adapt to the changes of the service providers.
Cryptocurrency such as Bitcoin is a rapidly developing phenomenon in financial technology with considerable research interest but is understudied. In this research article, we use a Design Science Research paradigm to create a high-frequency trading strategy at the minute level for Bitcoin using six exchanges as our Information Technology artifact. We created financial indicators and utilized a machine learning (ML) algorithm to create our strategy. We provided two sets of evaluation. First, we evaluated this strategy against another popular ML algorithm and found our algorithm performed better on the average. Second, we analyzed the economic benefits using the strategy against out-of-sample trading in foreign exchange currency. We presented both descriptive and prescriptive contributions to Design Science Research via the development and testing of our artifacts.
Monero is a privacy-centric cryptocurrency that makes payments untraceable by adding decoys to every real input spent in a transaction. Two studies from 2017 found methods to distinguish decoys from real inputs, which enabled traceability for a majority of transactions. Since then, a number protocol changes have been introduced, but their effectiveness has not yet been reassessed. Furthermore, little is known about traceability of Monero transactions across hard fork chains. We formalize a new method for tracing Monero transactions, which is based on analyzing currency hard forks. We use that method to perform a (passive) traceability analysis on data from the Monero, MoneroV and Monero Original blockchains and find that only a small amount of inputs are traceable. We then use the results to estimate the effectiveness of known heuristics for recent transactions and find that they do not significantly outperform random guessing. Our findings suggest that Monero is currently mostly immune to known passive attack vectors and resistant to tracking and tracing methods applied to other cryptocurrencies.
Sebastián Martínez, Laura Valderrama, Luis Sánchez
En el articulo se expone la influencia que va a tener la moneda virtual llamada Bitcoin en la economia colombiana, analizando los factores que afectan el creciente uso de esta y como las empresas tienen que prepararse a este nuevo medio de pago que dia a dia se vuelve mas popular, se analizaron diferentes temas que le permiten al lector comprender un poco mas esta nueva moneda virtual. Ambitos como el politico, ambiental, legal, tecnologico y social son los mas afectados con la implementacion de esta tecnologia, a su vez las empresas colombianas deben implementar medidas para responder adecuadamente ante esta, obtener la informacion necesaria y acertada va a ser imprescindible para que se aproveche esto como la oportunidad que representa. Ventajas como las plataformas de internet que promocionan las empresas que admiten el Bitcoin como medio de pago, pueden ser aprovechadas para hacer crecer los pequenos negocios por medio de esta tecnologia. El Bitcoin representa una clara amenaza para el poder del estado en el sistema financiero, por lo que su regulacion debe ser rapida y eficiente. Existe mucha especulacion entre las personas, puesto que hay pronunciaciones que dicen que en Colombia esta prohibido su uso, pero la posibilidad de usar Bitcoin en distintas plataformas, y hasta el lanzamiento de cajeros, crean mucha confusion en las personas. Las empresas deben prevenir el riesgo de ataques ciberneticos, ya que las monedas son almacenadas de forma virtual y no existe entidad que deposite o que custodie las reservas de esta moneda.
Gajendra J. Katuwal, Sandip Pandey, Mark Hennessey, Bishal Lamichhane
Several problems in healthcare stem from the complex network of intermediaries and the lack of traceability of transactions. To mention a few: healthcare data is fragmented across several silos negatively affecting research and services, about half of the clinical trials are never reported, the cost of drug discovery is ever increasing, and substandard and fake medicines are still a huge problem. Blockchain has the potential to solve these problems as it provides trust without any intermediaries, has traceability as a default feature, and promises new business models by enabling novel incentive structures. Due to its potential, blockchain has gathered significant interest in the healthcare industry. In this paper, we review major use cases of blockchain in healthcare: patient data management, pharmaceutical research, supply chain management of medical goods, prescription management, billing claims management, analytics, and telemedicine alongside the related projects. We found that most of the blockchain projects are limited as white-papers, proof of concepts, and products with a limited user base. However, we observed that the quantity, quality, and maturity of the projects are increasing. We also discuss technical, regulatory, and business challenges to the adoption of blockchain in the healthcare industry
Blockchains have recently been under the spotlight due to the boom of cryptocurrencies and decentralized applications. There is an increasing demand for querying the data stored in a blockchain database. To ensure query integrity, the user can maintain the entire blockchain database and query the data locally. However, this approach is not economic, if not infeasible, because of the blockchain's huge data size and considerable maintenance costs. In this paper, we take the first step toward investigating the problem of verifiable query processing over blockchain databases. We propose a novel framework, called vChain, that alleviates the storage and computing costs of the user and employs verifiable queries to guarantee the results' integrity. To support verifiable Boolean range queries, we propose an accumulator-based authenticated data structure that enables dynamic aggregation over arbitrary query attributes. Two new indexes are further developed to aggregate intra-block and inter-block data records for efficient query verification. We also propose an inverted prefix tree structure to accelerate the processing of a large number of subscription queries simultaneously. Security analysis and empirical study validate the robustness and practicality of the proposed techniques.
Shinichiro Tsuchiya, Issaku Yamada, Kiyoko F. Aoki‐Kinoshita
MOTIVATION: Glycans are biomolecules that take an important role in the biological processes of living organisms. They form diverse, complicated structures such as branched and cyclic forms. Web3 Unique Representation of Carbohydrate Structures (WURCS) was proposed as a new linear notation for uniquely representing glycans during the GlyTouCan project. WURCS defines rules for complex glycan structures that other text formats did not support, and so it is possible to represent a wide variety glycans. However, WURCS uses a complicated nomenclature, so it is not human-readable. Therefore, we aimed to support the interpretation of WURCS by converting WURCS to the most basic and widely used format IUPAC. RESULTS: In this study, we developed GlycanFormatConverter and succeeded in converting WURCS to the three kinds of IUPAC formats (IUPAC-Extended, IUPAC-Condensed and IUPAC-Short). Furthermore, we have implemented functionality to import IUPAC-Extended, KEGG Chemical Function (KCF) and LinearCode formats and to export WURCS. We have thoroughly tested our GlycanFormatConverter and were able to show that it was possible to convert all the glycans registered in the GlyTouCan repository, with exceptions owing only to the limitations of the original format. The source code for this conversion tool has been released as an open source tool. AVAILABILITY AND IMPLEMENTATION: https://github.com/glycoinfo/GlycanFormatConverter.git. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.
Olena Chygryn, Yuriy Petrushenko, Alina Vysochyna, Анна Воронцова
Testing the hypothesis of FD's positive influence on different parameters of social and economic development was realized on the base of panel data analysis for the set of European countries (Albania, Bosnia and Herzegovina, Bulgaria, Croatia, Macedonia, Moldova, Montenegro, Romania, Serbia, Slovenia, Turkey and Ukraine). Methodologically it was realized through the using of panel data regression model (independent variablesmeasures of fiscal decentralization, dependent variablesmeasures of social or economic development) in Stata 12/SE. This research allowed to confirm the hypothesis on positive impact of different measures of fiscal decentralization on GDP, GDP growth rate, foreign direct investments, and social contributions. Nevertheless, negative impact of fiscal decentralization on GNI per capita and export of goods and services was found. Besides, increase of public finance centralization stimulates inflation. There was identified controversial impact of different parameters of fiscal decentralization on dynamic of import of goods and services, accordingly.
We introduce Casanova, a leaderless optimistic consensus protocol designed for a permissioned blockchain. Casanova produces blocks in a DAG rather than a chain, and combines voting rounds with block production by singling out individual conflicting transactions.
There has been an unprecedented surge in the number of service providers offering a wide range of machine learning prediction APIs for tasks such as image classification, language translation, etc. thereby monetizing the underlying data and trained models. Typically, a data owner (API provider) develops a model, often over proprietary data, and leverages the infrastructure services of a cloud vendor for hosting and serving API requests. Clearly, this model assumes complete trust between the API Provider and cloud vendor. On the other hand, a malicious/buggy cloud vendor may copy the APIs and offer an identical service, under-report model usage metrics, or unfairly discriminate between different API providers by offering them a nominal share of the revenue. In this work, we present the design of a blockchain based decentralized trustless API marketplace that enables all the stakeholders in the API ecosystem to audit the behavior of the parties without having to trust a single centralized entity. In particular, our system divides an AI model into multiple pieces and deploys them among multiple cloud vendors who then collaboratively execute the APIs. Our design ensures that cloud vendors cannot collude with each other to steal the combined model, while individual cloud vendors and clients cannot repudiate their input or model executions.
With the more and more extensive application of blockchain, blockchain security has been widely concerned by the society and deeply studied by scholars. Moreover, the security of blockchain data directly affects the security of various applications of blockchain. In this survey, we perform a comprehensive classification and summary of the security of blockchain data. First, we present classification of blockchain data attacks. Subsequently, we present the attacks and defenses of blockchain data in terms of privacy, availability, integrity and controllability. Data privacy attacks present data leakage or data obtained by attackers through analysis. Data availability attacks present abnormal or incorrect access to blockchain data. Data integrity attacks present blockchain data being tampered. Data controllability attacks present blockchain data accidentally manipulated by smart contract vulnerability. Finally, we present several important open research directions to identify follow-up studies in this area.
Open access
2 source records
Blockchain Technology Applications and Security
Advanced Steganography and Watermarking Techniques
Zeeshan Jan, Allan Third, Michelle Bachler, John Domingue
Peer-reviewing holds a significant importance in the process of scientific publishing. The process of peer-reviewing has been criticized for its defects, but research communities have faith in it, and hence, it is perceived as the backbone of scientific publishing. The process needs improvements in a number of ways, i.e, establishing trust in the pro- cess, preventing abuse, bringing transparency in the process and keeping the integrity of data intact. Moreover, the activity of peer-reviewing is carried out without any formal incentives. We present considerations in refreshing peer-review, and our approach to experiment in this space.
With the more and more extensive application of blockchain, blockchain security has been widely concerned by the society and deeply studied by scholars. Moreover, the security of blockchain data directly affects the security of various applications of blockchain. In this survey, we perform a comprehensive classification and summary of the security of blockchain data. First, we present classification of blockchain data attacks. Subsequently, we present the attacks and defenses of blockchain data in terms of privacy, availability, integrity and controllability. Data privacy attacks present data leakage or data obtained by attackers through analysis. Data availability attacks present abnormal or incorrect access to blockchain data. Data integrity attacks present blockchain data being tampered. Data controllability attacks present blockchain data accidentally manipulated by smart contract vulnerability. Finally, we present several important open research directions to identify follow-up studies in this area.
Open access
Blockchain Technology Applications and Security
Privacy-Preserving Technologies in Data
Advanced Steganography and Watermarking Techniques
Learning analytics and data mining require gathering and exchanging learner data for further processing and designing of activities tailored to learner’s characteristics, context, and needs. Currently, systems that store learners’ attributes should, ideally, be operated and controlled by responsible and trustworthy authorities that guarantee the protection and sovereignty of data and use objective criteria to protect and represent all parties’ interests. This chapter introduces a peer-to-peer method for storing and exchanging learner data with minimal trust. The proposed approach, underpinned by the Experience API standard, eliminates the need of a mediator authority by using distributed ledger technology.
The traditional Medical Education ecosystems are largely centralised and confined to the boundaries of academic institutions. Rather than promoting efficiency and global forward thinking, a number of medical institutions have become inwardly focused, confining themselves to their own institutional rules and frameworks. In the past two years, the utility of blockchain in the higher education setting has been extensively studied. A blockchain is essentially a distributed, immutable, trustworthy, decentralised database that keeps an irreversible, time-stamped record of transfer of value between users for every operation that has ever been carried out on its network. This has traditionally been used in cryptocurrency transactions, however, with the rise of blockchain based Decentralised Applications (DApps), the potential benefits of this ground-breaking technology in higher education are now being explored. Although still in the early developmental stages, blockchain holds promising potential for use in medical education. Some of these are budding hypothesis while in other areas, we have witnessed real, tangible progress. This article analyses the potential use cases for blockchain deployment in medical education ecosystems, to improve the efficiency, security, functionality and effectiveness of existing infrastructures. We conclude the essay by proposing how blockchain can eliminate the growing problem of fraudulent academic accreditations