Next to artificial intelligence and big data, blockchains have emerged as one of the most oft-cited technologies associated with the digital economy. Leading technology companies have recently contributed to making the technology used more widely by developing integrated blockchain offerings. The emergence of such services yet strikingly clashes with the original stated goal of the technology to remove any form of central political authority, such as the one companies behind these new services can represent. How should we then understand the embrace of blockchains by companies that this technology was notably supposed to displace? Using the concept of infrastructure from Science and Technology Studies, we argue that these companies are not merely adopting the technology but actively promoting a new assemblage of socio-technical devices to reassert their authority over how information is exchanged online. Based on a comparative analysis of the technical documentation of Ethereum and Amazon Web Services (AWS) blockchain services, we highlight how actors contributing to building digital infrastructures regulate their users' behavior by affording them different capacities and constraints. We moreover show how by pursuing its commercial interest, AWS supported a corporate form of governance historically promoted by the United States to oversee the digital economy.
With the recent emergence of the smart healthcare era, and patients relying more on personalized health monitoring based on Internet of Medical Things (IoMT) devices; patients’ lives are becoming highly threatened in case they fall victim to counterfeit devices. Thus, verifying whether these body sensors utilized are authentic and reliable in an unimpeachable, credible, and auditable manner without any centralized management is of crucial importance. Furthermore, manipulating data and hijacking in an IoMT context are also of tremendous criticality. Motivated by the aforementioned challenges, in this article, a smart contract-based scalable authentication scheme dedicated for IoMT devices is proposed. The scheme mitigates the deficiencies of the traditional established systems that are extensively built on centralized approaches, vulnerable to distributed denial of service attacks, by leveraging blockchain’s decentralization and security properties. The scheme ensures confidentiality, anonymity, and privacy as it is built on a consortium blockchain and integrity by offering secure firmware updates and protects patients from counterfeit devices by leveraging the physical unclonable function. The authentication approach was implemented on Ethereum and evaluated with regard to its computation and communication costs to prove its feasibility and effectiveness as well as its security by presenting a formal analysis using ProVerif.
Blockchain Technology Applications and Security
Neuroethics, Human Enhancement, Biomedical Innovations
In this paper, we propose a Peer-to-Peer (P2P) energy trading scheme between EVs and the SPs to manage the demand response in V2G environment. Unlike the traditional schemes, which consists of complex energy-transportation meshes, the proposed scheme achieves a balance between demand and response by providing incentives to EVs out of their self-interests. However, the online transactions security and privacy protection of EVs poses challenges with respect to confidentiality and integrity preservation. To cope up with the issues, we design a consortium blockchain-based scheme to ensure secure energy transactions between EVs and the SPs without trusted third-party intervention. Moreover, the energy pricing and the amount of traded energy problems for demand response are solved by a double auction mechanism to maximize the social welfare. Numerical results based on a real-time implementation on a private Ethereum network having smart contract demonstrated that the auction-based mechanism achieves social welfare maximization with privacy protection of online transactions between EVs and the SPs. The results obtained show that the rate of convergence, scalability metric average latency, and standard deviation of the energy transactions have been improved by approximately 18.18%, 15%, and 28.1%, respectively in comparison to the existing schemes. Moreover, security and privacy analysis of the proposed scheme shows that it improves the transaction security substantially in comparison to the existing state-of-the-art proposals.
The existing agriculture system is having several components such as supply chain management, crop insurance, the shipment of goods, and it involves numerous untrusted stakeholders such as users (farmers, retailers, customers, wholesalers, etc.), agencies (bank, insurance company) and regulators (assessor, surveyors). Due to the active engrossment of the middle man (mostly human beings or agencies operated by human beings) some key issues are raised such as transparency, timeliness, traceability, security, and immutability resulting in financial loss, crop contamination, and spoilage. Secure distributed public ledger technology and decentralized computing paradigm make Blockchain an appropriate alternative to resolve these issues and to achieve profitability & trust for all its stakeholders. In this research, we intend to propose a Blockchain-based mechanism viz. AgriOnBlock which would address the issues mentioned in the agriculture sector by connecting various stakeholders through the usage of IoT devices and smart contracts in Ethereum. We further discuss implications, constraints (methodological, awareness related, regulatory, etc.), and potential for actual adoption of AgriOnBlock.
Purpose After the COVID-19 outbreak, the Federal Reserve has undertaken several monetary policies to alleviate the pandemic consequences on the stock markets leading to a misunderstanding on the cryptocurrency market response. This paper aims to evaluate the effects of the Federal Reserve monetary policy on the Islamic and conventional cryptocurrency dynamics during the COVID-19 pandemic. We, specifically, examine the associate bubbles and feedbacks effects. Design/methodology/approach This paper developed a novel methodology that detects market bubbles using the statistical indicators defined by Psychological (PSY) tests. It also investigated the effect of the Federal Open Market Committee (FOMC) announcements on conventional and Islamic cryptocurrencies compatible with Islamic laws “Shari’ah” by using the event-driven regression. Findings The empirical results show that the FOMC announcements have a positive significant effect after one day of the event and a negative effect before two days of the announcement on the conventional cryptocurrency markets. However, the reaction of Islamic cryptocurrencies to these events is not significant except for Hello Gold after one day of the announcement. Besides, the Hello Gold and X8X cryptocurrencies present no bubbles during this period. However, Bitcoin and Ethereum markets have short-lived bubbles. Research limitations/implications The main contribution of this study is the investigation of the response and vulnerability to pandemic shocks of a new category of cryptocurrencies backed by tangible assets. This work has practical implications as it provides new insights into trading opportunities and market reactions. Originality/value To our knowledge, this work is the first study that compares the response of Islamic and conventional cryptocurrency markets to FOMC announcements during the COVID-19 pandemic and examines the presence of bubbles in these markets. Besides, the originality of this work is derived from the novelty of the data employed and the method used (PSY tests) in this study.
The rise of Ethereum and other blockchains that support smart contracts has led to the creation of decentralized exchanges (DEXs), such as Uniswap, Balancer, Curve, mStable, and SushiSwap, which enable agents to trade cryptocurrencies without trusting a centralized authority. While traditional exchanges use order books to match and execute trades, DEXs are typically organized as constant function market makers (CFMMs). CFMMs accept and reject proposed trades based on the evaluation of a function that depends on the proposed trade and the current reserves of the DEX. For trades that involve only two assets, CFMMs are easy to understand, via two functions that give the quantity of one asset that must be tendered to receive a given quantity of the other, and vice versa. When more than two assets are being exchanged, it is harder to understand the landscape of possible trades. We observe that various problems of choosing a multi-asset trade can be formulated as convex optimization problems, and can therefore be reliably and efficiently solved.
The rise of Ethereum and other blockchains that support smart contracts has\nled to the creation of decentralized exchanges (DEXs), such as Uniswap,\nBalancer, Curve, mStable, and SushiSwap, which enable agents to trade\ncryptocurrencies without trusting a centralized authority. While traditional\nexchanges use order books to match and execute trades, DEXs are typically\norganized as constant function market makers (CFMMs). CFMMs accept and reject\nproposed trades based on the evaluation of a function that depends on the\nproposed trade and the current reserves of the DEX. For trades that involve\nonly two assets, CFMMs are easy to understand, via two functions that give the\nquantity of one asset that must be tendered to receive a given quantity of the\nother, and vice versa. When more than two assets are being exchanged, it is\nharder to understand the landscape of possible trades. We observe that various\nproblems of choosing a multi-asset trade can be formulated as convex\noptimization problems, and can therefore be reliably and efficiently solved.\n
Hassan Farran, David Khoury, Elie Kfoury, László Bokor
The security proposed for Vehicle-to-Everything (V2X) systems in the European Union is specified in the ETSI Cooperative Intelligent Transport System (C-ITS) standards, and related documents are based on the trusted PKI/CAs. The C-ITS trust model platform comprises an EU Root CA and additional Root CAs run in Europe by member state authorities or private organizations offering certificates to individual users. A new method is described in this paper where the security in V2X is based on the Distributed Public Keystore (DPK) platform developed for Ethereum blockchain. The V2X security is considered as one application of the DPK platform. The DPK stores and distributes the vehicles, RSUs, or other C-ITS role-players’ public keys. It establishes a generic key exchange/ agreement scheme that provides mutual key, entity authentication, and distributing a session key between two peers. V2X communication based on this scheme can establish an end-to-end (e2e) secure session and enables vehicle authentication without the need for a vehicle certificate signed by a trusted Certificate Authority.
In this paper, we investigated the evolution of user behavior on Ethereum through building directed and weighted external owned accounts trading networks (DWETN) from August 10th, 2015 to June 9th, 2017. It is showed that the evolution of the structural properties of the DWETN and important events are closely related. The relationship between the number of users and the total number of transactions is linear, and each user will have 1.5 transactions on average. Out-degree, in-degree, out-strength, and in-strength distributions follow the power-law distributions, and the power exponent values of out-degree and in-degree distributions change much more than out-strength and in-strength distributions, which implies that, despite the changes in network structure, the transaction behavior pattern of users have inherent stability. The evolution of directed degree correlation coefficients and directed and weighted Pearson correlation coefficients of the network indicates that in-degree(in-strength) of the source node of an edge has a weak effect on the target node's in-degree(in-strength) and out-degree(out-strength), and as time evolves, the effect of out-degree(out-strength) of the source node of an edge on the target node's in-degree(in-strength) and out-degree(out-strength) from negative to weak.
Ethereum sebagai salah satu cryptocurrency yang transaksinya dapat dilakukan tanpa membutuhkan kartu kredit atau melalui bank sentral, akan tetapi cryptocurrency mengalami fluktuasi terhadap harga yang berubah secara periode tertentu. Risiko fluktuasi harga ini dapat diantisipasi dengan melakukan prediksi terhadap nilai tukarnya, penelitian ini menggunakan kurs Dollar Amerika Serikat sebagai acuan nilai tukar setiap satu Ethereum. Prediksi yang dilakukan menggunakan pendekatan Vector Autoregressive untuk melakukan analisis data dalam bentuk time series. Berdasarkan hasil penelitian yang telah dilakukan diketahui bahwa hasil perhitungan nilai error menggunakan Root Mean Square Error yaitu nilai error pada harga pembukaan 890,29, nilai error pada harga tertinggi 930,50, nilai error pada harga terendah 1.164,12 dan nilai error pada harga penutupan 978,37.
The study presents a blockchain-based incentive mechanism intended to encourage those in underserved communities to engage with healthcare services. The smart healthcare system, which is the result of the amalgamation of advanced technologies, has emerged recently and is increasingly seen as essential to meet the needs of modern society. An important part of the healthcare system is the prescription management system, but studies show that prescription affordability and accessibility play a part in creating unequal access for underserved communities. This is a form of unequal access that results in those living in underserved communities to become disengaged from accessing healthcare services. In New Zealand, the prescription management system plays a crucial role and this study seeks to address the issue by presenting the BlockPres framework, which uses a novel incentive mechanism to encourage patients to participate and engage with services in order to be rewarded. The blockchain attribute of immutability in BlockPres enhances equality and participation by providing sophisticated authorisation and authentication capabilities for healthcare providers and patients. BlockPres empowers the patient by assigning ownership or control of some patient information to the patient. A simulation is carried out using the Ethereum blockchain and the evaluation of successful transaction completion and superficial performance assessment demonstrates that the blockchain would be sufficient to cope with the needs of a prescription management system. Furthermore, for the simulation, a BlockPres Smart Contract is developed using solidity and implemented in Remix. The Ropsten network is used as the simulation environment and the initial results show that the proposed incentive mechanism mitigates unequal access.
Privacy preserving is a matter of great importance in many sensitive fields including financial and healthcare areas. As the blockchain technology has achieved an obvious success in privacy protection at the financial level when the Bitcoin has been introduced in 2008, there are considerable attempts and later on successful projects to introduce the blockchain technology to the healthcare fields, where the patient privacy and access control to the personal information is at high priority. The aim of our paper mainly considers the introduction of the smart contracts that are based on the blockchain technology as a method to preserve the patient privacy and improve the reality of dental healthcare providing services.The main focus will be on the treatment plan of the patient by building a smart contract system between multiple partners. By using “the five types models” our proposed system has been built combining the advantages of blockchain technology and the benefits of smart contracts. The programming language that we have used is Solidity along with proof of authority algorithm on Ethereum blockchain. The proposed smart contract system which is based on blockchain technology can provide the privacy preservation of patient information in addition to the digitalization of healthcare data.
Abstract Existing models for non-interactive MPC cannot provide full privacy for inputs, because they inherently leak the residual function (i.e., the output of the function on the honest parties’ input together with all possible values of the adversarial inputs). For example, in any non-interactive sealed-bid auction, the last bidder can figure out what was the highest previous bid. We present a new MPC model which avoids this privacy leak. To achieve this, we utilize a blockchain in a novel way, incorporating smart contracts and arbitrary parties that can be incentivized to perform computation (“bounty hunters,” akin to miners). Security is maintained under a monetary assumption about the parties: an honest party can temporarily supply a recoverable collateral of value higher than the computational cost an adversary can expend. We thus construct non-interactive MPC protocols with strong security guarantees (full security, no residual leakage) in the short term. Over time, as the adversary can invest more and more computational resources, the security guarantee decays. Thus, our model, which we call Gage MPC, is suitable for secure computation with limited-time secrecy, such as auctions. A key ingredient in our protocols is a primitive we call “Gage Time Capsules” (GaTC): a time capsule that allows a party to commit to a value that others are able to reveal but only at a designated computational cost. A GaTC allows a party to commit to a value together with a monetary collateral. If the original party properly opens the GaTC, it can recover the collateral. Otherwise, the collateral is used to incentivize bounty hunters to open the GaTC. This primitive is used to ensure completion of Gage MPC protocols on the desired inputs. As a requisite tool (of independent interest), we present a generalization of garbled circuit that are more robust: they can tolerate exposure of extra input labels. This is in contrast to Yao’s garbled circuits, whose secrecy breaks down if even a single extra label is exposed. Finally, we present a proof-of-concept implementation of a special case of our construction, yielding an auction functionality over an Ethereum-like blockchain.
Purpose The rapid technological growth, changes in consumer demands, products’ built-in obsolescence, presence of more non-repairable parts, shorter lifespan, etc., lead to the generation of e-waste at an unprecedented rate. Although a number of research proposals and business products to manage e-waste exist in the literature, they lack in many aspects such as incomplete coverage of product’s life cycle, access control, payment channels (in few cases), incentive mechanisms, scalability issues, and missing experimental validation. The purpose of this paper is to introduce a novel blockchain-based e-waste management system aiming to mitigate the above-mentioned downsides and limitations of the existing proposals. Design/methodology/approach This paper proposes a robust and reliable e-waste management system by leveraging the power of blockchain technology, which captures the complete life cycle of e-products commencing from their manufacturing as new products to their disposal as e-waste and their recycling back into raw materials. Findings While the use of blockchain technology increases accountability, transparency and trust in the system, the proposal overcomes various challenges and limitations of the existing systems by providing seamless interactions among various agencies. Originality/value This paper presents a prototype implementation of the system as a proof-of-concept using solidity on the Ethereum platform and this paper performs experimental evaluations to demonstrate its feasibility and effective performance in terms of execution gas cost and transaction throughput.
Nuke Puji Lestari, Yusuf Durachman, Srie Watini, Shofiyul Millah
Banyak pengguna menggunakan internet sebagai alat untuk layanan informasi yang lebih baik di lembaga pendidikan. Jaringan ini tidak memiliki penyedia layanan yang bertindak sebagai otoritas pusat dan pengguna memiliki kontrol lebih besar atas informasi mereka sehingga tidak ada pihak ketiga. Sehingga diusulkan sebagai solusi alternatif untuk sistem pembelajaran jaringan terpusat saat ini menggunakan Decentralized Online Educations (DOE). Banyak DOE telah diusulkan, namun keberadaan layanan Decentralized Online Educations (DOE) membutuhkan solusi terdistribusi yang efisien untuk melindungi privasi pengguna. Dalam beberapa tahun terakhir, banyak teknologi blockchain telah diimplementasikan ke dalam sistem pembelajaran sehingga sangat cocok untuk institusi pendidikan yang digunakan untuk menyelesaikan masalah privasi dalam sistem desentralisasi. Pada platform ini, menggunakan teknologi blockchain sebagai sistem penyimpanan, dan materi pembelajaran yang bersifat publik. Dalam studi ini, buat kerangka kerja kontrol akses yang dapat dikelola dan diaudit untuk Decentralized Online Educations (DOE) menggunakan teknologi blockchain untuk membahas definisi kebijakan privasi. Kunci publik yang digunakan oleh pemilik sumber daya menggunakan dari subjek untuk menentukan kebijakan akses dapat diaudit menggunakan Access Control List (ACL), sedangkan untuk mendekripsi data pribadi setelah izin akses divalidasi di blockchain menggunakan kunci pribadi yang terkait dengan akun Ethereum subjek. Untuk memberikan evaluasi dari pendekatan ini, gunakan testnet Rinkeby Ethereum untuk mengimplementasikan Kontrak Cerdas. Dan hasil dari percobaan ini dapat menunjukkan bahwa Access Control List (ACL) yang diusulkan menggunakan Attribute-Based Access Control (ABAC) dalam sistem pembelajarannya. Untuk mewujudkannya, diperlukan Access Control List (ACL).
Blockchain is a method of storing data that makes it extremely difficult, if not impossible, to edit, hack, or update the system. As time passes, blockchain technology becomes more popular, and blockchain-based applications, also known as DApps, which will be used in this article, are becoming more widely recognised. We will construct a chat application based on a decentralised network in this article to eliminate its absolute reliance on centralised players. On a peer-to-peer network like Ethereum, the actual message and data will be kept. To offer decentralised storage and efficient lookup, we will employ a blockchain and distributed hash table (DHT). which will describe what we will do, which is a trendy issue among academics and trades. Except for the fact that DApps are important, we currently have a limited grasp of DApps and nature. To close the data gap, this paper presents a file for the most comprehensive blockchain-based DApps analysis to date, which includes 995 Ethereum DApps data and 29,846,075 dealings logs above them. We usually do a descriptive investigation of Dapp preferences, characterise patterns of how Dapps use good contracts to gain access to fundamental blockchain, and evaluate the results issues with the post and misuse of DApps In support of the findings, we propose a large number of Results for DApp users to choose the best DApps. Dapp developers must work harder in order to create more efficient DApps, and vendors must likewise support them.