PURPOSE The healthcare system in the United States is unique. From payor to provider, patients have many choices but they lack in the ability to manage or share their health information. This complicated care paradigm places patients at a distinct disadvantage. Legislation clearly defines government expectations of data availability but not how to achieve exchange. Because methods of sharing are left to the discretion of care providers and software vendors, non-interoperability is the standard. METHODS The OpenPharma Blockchain on Fast Healthcare Interoperability Resources (FHIR) (OBF) solution is interoperable by design. OBF empowers patients with data access through biometric identity authentication, blockchain, and machine-–to-machine secure data access. OBF provides authenticated users read-only, real-time access to patient records using the healthcare interoperability standard HL7 FHIR. OBF is built around a modern, browser-based user interface, blockchain technologies (leveraging either Ethereum or the Hedera protocols) and modular, modern software exposed as Application Programming Interfaces (APIs). This allows OBF to meet the Office of National Coordinator for Health Information (ONC) metrics, which include sending, receiving, and finding information from outside sources and using that information to make informed clinical decisions without additional burden on clinicians or patients. RESULTS Building on the HL7 FHIR application community practices, OBF is a SMART-on-FHIR plug-in for Electronic Medical Record (EMR) systems. Using OBF, patients can identify themselves and gain access to their medical records using their voice. This unique feature is accomplished through the Saavha voice print biometrics technology. Saavha returns a unique member ID that is passed directly to the OBF blockchain smart contract for storage and interoperable patient record access (the ID does not contain public health information [PHI]). To ensure complete privacy, all information is passed through multiple layers of encryption where no keys are stored locally. Additionally, no PHI is shared to the blockchain. To ensure privacy, OBF creates a new encrypted address for the FHIR patient record object, using the Saavha generated member ID as the unique identifier. This encrypted address is then published on chain, making it available to participating providers. Providers must register their relationships to patients before OBF will permit online viewing of patient records. Patient record access is accomplished through voice verification and real-time surfacing of encrypted patient data through the OBF FHIR Viewer. CONCLUSIONS OBF is a lightweight, flexible, secure, and stable interoperable solution that places data stewardship with patients. Using industry-wide data standards, biometrics, Smart contracts, Ethereum, and OpenPharma’s data viewer for the first-time patients can authorize read-only record exchange using their voice.
ABSTRACT: The banking sector has undergone tremendous changes in the past decades. This paper seeks to investigate the future of Kenya banks by using cryptocurrency and blockchain technology to mitigate financial risk. A cryptocurrency performs the fundamental function of money, as a medium of exchange. The encryption and decentralization of digital currencies are the most important aspects regarding the applicability of Cryptocurrencies and Blockchain Technology in Kenya. Digital money supports individual investors as opposed to a dominant market player or authority. The fact that no single authority controls cryptocurrencies is the heart of its applicability in Kenya. Digital money is a unifying factor for the world markets defined by growing inequality and financial malpractices. The Kenyan banking system may take advantage of the smart contracts to address the myriad risks owed to the economic actions of the private and public parties. Banks can use the digital money to eliminate intermediaries that often constrain the capacity of the individual traders to enter into contracts. Cryptocurrencies operate on a user-to-user basis to enhance flexibility and control by the individual traders. The use of the technology can help the state to reduce the risk of loss owed to inaccurate authentication and valuation of assets. KEYWORDS: cryptocurrencies, blockchain technology, financial institutions, market risks, Kenia, banking system
We introduce Unity Interleave, a new consensus algorithm for public blockchain settings. It is an eventual consistency protocol merging the Proof-of-Work (PoW) and Proof-of-Stake (PoS) into a coherent stochastic process. It builds upon research previously done for the Unity protocol, improving security while maintaining fairness and scalability.
We live in an era of information and it is very important to handle the exchange of information. While sending data to an authorized source, we need to protect it from unauthorized sources, changes, and authentication. ZKP technique can be used in designing secure authentication systems that dont involve any direct exchange of information between the claimant and the verifier thus preventing any possible leak of personal information. We propose a Zero-Knowledge Proof (ZKP) algorithm based on isomorphic graphs. We suggest most of the computations should be carried out on the users' web browser without revealing the password to the server at any point in time. Instead, it will generate random graphs and their permutations based on the login ID and password.
As a blockchain platform that has developed vigorously in recent years, Ethereum is different from Bitcoin in that it introduces smart contracts into blockchain.Solidity is one of the most mature and widely used smart contract programming language,which is used to write smart contracts and deploy them on blockchain. However, once the data in the blockchain is written, it cannot be modified. Ethereum smart contract is stored in the block chain, which makes the smart contract can no longer repair the code problems such as re-entrancy vulnerabilities or integer overflow problems. Currently, there still lacks of an efficient and effective approach for detecting these problems in Solidity. In this paper, we first classify all the possible problems in Solidity, then propose a smart contract problem detection approach for Solidity, namely SolidityCheck. The approach uses regular expressions to define the characteristics of problematic statements and uses regular matching and program instrumentation to prevent or detect problems. Finally, a large number of experiments is performed to show that SolidityCheck is superior to existing approaches.
The Global South harbors some of the planet’s most precious natural resources and is hence key in addressing the pressing environmental challenges of the Anthropocene. Here, payments for ecosystem services (PES) have recently gained importance as a means of environmental governance, increasingly complementing conventional command-and-control approaches. For instance, climate change is now mitigated through carbon offset payments and biodiversity loss is addressed through wildlife conservation performance payments. However, such payment schemes in the Global South face numerous challenges as identified by a large body of literature. This paper investigates if blockchain technology can help address some of the challenges by reinforcing PES programs with tamper-proof blockchain smart contracts. To this end, the paper presents a proof-of-concept of a blockchain-based wildlife conservation performance payments scheme in Namibia: the habitat integrity of an elephant corridor is assessed by remote sensing algorithms, which in turn trigger fictitious blockchain smart contract payments to surrounding communities. The application allows to practically discuss the potential of blockchain technology regarding three key aspects of PES: (i) effectiveness (conditionality) of environmental monitoring (ii) efficiency and transaction costs, as well as (iii) equity and benefit distribution. The case presented here is an example for linking the digital Blockchain sphere to practical challenges of natural resource management in the physical world. As such, it illustrates some potentials of the technology, but also shows how Blockchain technology is unlikely to provide transformative solutions in geographies with complex environmental governance.
Open access
Conservation, Biodiversity, and Resource Management
Abstract Smart contracts are scripts on the top of the blockchain technology. They represent a form of automation by what the layers of intermediaries can be reduced or even completely replaced. Accordingly, blockchain smart contracting systems decrease transaction and enforcement costs as well as process time. Moreover, we argue, blockchain and smart contracts can facilitate cross-organisational collaboration and their underlying business processes. Hence, they are able to support the integration of entrepreneurs and SMEs into trans-national supply chains by reducing high entry barriers and weakening the dominating position of big players. This paper discusses the research questions how blockchain smart contracting can facilitate the implementation of collaborative logistics structures and how the integration of SMEs into sustainable maritime supply chains can be safeguarded. The research bases on expert interviews and case studies. The results showcase the potentials of using blockchain smart contracting in the environment of trans-national and multimodal supply chains.
Since the inception of Bitcoin, the distributed systems community has shown interest in the design of efficient blockchain systems. However, initial blockchain applications (like Bitcoin) attain very low throughput, which has promoted the design of permissioned blockchain systems. These permissioned blockchain systems employ classical Byzantine-Fault Tolerant (BFT) protocols to reach consensus. However, existing permissioned blockchain systems still attain low throughputs (of the order 10K txns/s). As a result, existing works blame this low throughput on the associated BFT protocol and expend resources in developing optimized protocols. We believe such blames only depict a one-sided story. In specific, we raise a simple question: can a well-crafted system based on a classical BFT protocol outperform a modern protocol? We show that designing such a well-crafted system is possible and illustrate that even if such a system employs a three-phase protocol, it can outperform another system utilizing a single-phase protocol. This endeavor requires us to dissect a permissioned blockchain system and highlight different factors that affect its performance. Based on our insights, we present the design of our enterprise-grade, high-throughput yielding permissioned blockchain system, ResilientDB, that employs multi-threaded deep pipelines, to balance tasks at a replica, and provides guidelines for future designs.
Stanisław Drożdż, Ludovico Minati, Paweł Oświȩcimka, Marek Stanuszek · 5 authors
Cross correlations in fluctuations of the daily exchange rates within the basket of the 100 highest-capitalization cryptocurrencies over the period October 1, 2015-March 31, 2019 are studied. The corresponding dynamics predominantly involve one leading eigenvalue of the correlation matrix, while the others largely coincide with those of Wishart random matrices. However, the magnitude of the principal eigenvalue, and thus the degree of collectivity, strongly depends on which cryptocurrency is used as a base. It is largest when the base is the most peripheral cryptocurrency; when more significant ones are taken into consideration, its magnitude systematically decreases, nevertheless preserving a sizable gap with respect to the random bulk, which in turn indicates that the organization of correlations becomes more heterogeneous. This finding provides a criterion for recognizing which currencies or cryptocurrencies play a dominant role in the global cryptomarket. The present study shows that over the period under consideration, the Bitcoin (BTC) predominates, hallmarking exchange rate dynamics at least as influential as the U.S. dollar (USD). Even more, the BTC started dominating around the year 2017, while other cryptocurrencies, such as the Ethereum and even Ripple, assumed similar trends. At the same time, the USD, an original value determinant for the cryptocurrency market, became increasingly disconnected, and its related characteristics eventually started approaching those of a fictitious currency. These results are strong indicators of incipient independence of the global cryptocurrency market, delineating a self-contained trade resembling the Forex.
Payment channel networks like Bitcoin's Lightning network are an auspicious approach for realizing high transaction throughput and almost-instant confirmations in blockchain networks. However, the ability to successfully make payments in such networks relies on the willingness of participants to lock collateral in the network. In Lightning, the key financial incentive is to lock collateral are small fees for routing payments for other participants. While users can choose these fees, currently, they mainly stick to the default fees. By providing insights on beneficial choices for fees, we aim to incentivize users to lock more collateral and improve the effectiveness of the network. In this paper, we consider a node $\mathbf{A}$ that given the network topology and the channel details selects where to establish channels and how much fee to charge such that its financial gain is maximized. We formalize the optimization problem and show that it is NP-hard. We design a greedy algorithm to approximate the optimal solution. In each step, our greedy algorithm selects a node which maximizes the total reward concerning the number of shortest paths passing through $\mathbf{A}$ and channel fees. Our simulation study leverages real-world data set to quantify the impact of our gain optimization and indicates that our strategy is at least a factor two better than other strategies.
Shifeng Ding, Gangxiang Shen, Kevin X. Pan, Sanjay K. Bose · 6 authors
In communication networks, network virtualization can usually provide better capacity utilization and quality of service (QoS) than what can be achieved otherwise. Under this operation, once the capacity of a virtual optical network (VON) is allocated, it will be static for a certain period, for example, a service contract period. However, in reality, the actual traffic demand of a VON always fluctuates, which would lead to a mismatch between the capacity assigned and the actual traffic demand carried. This mismatch would further cause degradation of provisioned network services and inefficiency in assigned network capacity. To overcome this issue, we propose a new scheme, called spectrum trading (ST), to trade spectrum resources between VONs in the context of an elastic optical network (EON). The key idea is to allow different VONs to trade their spectrum resources according to their actual capacity requirement at different time instants. A VON with unused spectra can trade away its unused spectra to other VONs that are short of spectrum resources at that time. in exchange, it is rewarded with some credit for its contribution to the ST community, which it can then use later to obtain extra capacity, if needed. The trust-worthiness of the trading records between the VONs is ensured in a distributed fashion through a blockchain- assisted ledger that is updated whenever a new trade occurs. A software-defined control plane is also developed to enable spectrum trading with the support of the blockchain-assisted ledger. The performance of the ST scheme is evaluated and compared with the scenario without such trading. Results show that the proposed ST scheme is efficient in improving the QoS of each VON and significantly improves overall network capacity utilization.
Suyash Gupta, Jelle Hellings, Sajjad Rahnama, Mohammad Sadoghi
Since the introduction of Bitcoin---the first wide-spread application driven by blockchains---the interest of the public and private sector in blockchains has skyrocketed. At the core of this interest are the ways in which blockchains can be used to improve data management, e.g., by enabling federated data management via decentralization, resilience against failure and malicious actors via replication and consensus, and strong data provenance via a secured immutable ledger.
Ruth Árias, Manuel Pérez, Elisa López, Haideé Marín
This paper evaluates change scenarios in rural communities of the Kichwa Amazonian territory in the Anzu River Valley, Ecuador, in six communities, from Tzawata, at Northeast to Veinticuatro de Mayo at Southwest; at low, medium and high levels of the Anzu river valley. The communities settled since the end of the nineteenth century, came from the Napo province. Study area includes a portion of Kichwa original territory, fragmented by settler possessions, a process that also characterizes the territorial system of which the communities studied are part. The diversity of actors in this territory maintains a growing trend as the colonization process advances, also, the recognition of ancestral rights and community ownership of land, becomes more difficult. The decentralized autonomous local governments don’t have competence in the legalization of lands and territories, but they do have competence in the investment for development. The study detected local governments don’t include all the communities studied in their area of influence. On the other hand, already in this scenario it is detected that the knowledge of the use of local species is weakened in the communities, as well as their use. The irruption of legal and illegal mining and the persistent threat of oil exploitation create constant conflicts in the Kichwa nation. Strategic foresight, as the basis for the development of the territorial system and its application in the communities studied, necessarily recognizes the forms of indigenous and mestizo community social organization, their identity and ancestral values, times and rhythms of life.
Open access
Conservation, Biodiversity, and Resource Management
Blockchains, in a nutshell, are mechanisms used for creating artificial scarcity. They are a type of distributed database, or ledger, and a means to keep track of information shared among multiple parties. As you may know, blockchains are one of the IEEE Future Directions initiatives, with a growing number of IEEE Societies creating projects for blockchain-related standards development in the areas of agriculture, digital asset management, energy, finance, health care, the Internet of Things, and so on. In this article, the focus is mainly on cryptocurrency exchanges.
This paper sets forth a framework for deep reinforcement learning as applied to market making (DRLMM) for cryptocurrencies. Two advanced policy gradient-based algorithms were selected as agents to interact with an environment that represents the observation space through limit order book data, and order flow arrival statistics. Within the experiment, a forward-feed neural network is used as the function approximator and two reward functions are compared. The performance of each combination of agent and reward function is evaluated by daily and average trade returns. Using this DRLMM framework, this paper demonstrates the effectiveness of deep reinforcement learning in solving stochastic inventory control challenges market makers face.
Francesco Zola, Jan L. Bruse, Maria Eguimendia, Mikel Galar · 5 authors
The Bitcoin network not only is vulnerable to cyber-attacks but currently represents the most frequently used cryptocurrency for concealing illicit activities. Typically, Bitcoin activity is monitored by decreasing anonymity of its entities using machine learning-based techniques, which consider the whole blockchain. This entails two issues: first, it increases the complexity of the analysis requiring higher efforts and, second, it may hide network micro-dynamics important for detecting short-term changes in entity behavioral patterns. The aim of this paper is to address both issues by performing a “temporal dissection” of the Bitcoin blockchain, i.e., dividing it into smaller temporal batches to achieve entity classification. The idea is that a machine learning model trained on a certain time-interval (batch) should achieve good classification performance when tested on another batch if entity behavioral patterns are similar. We apply cascading machine learning principles—a type of ensemble learning applying stacking techniques—introducing a “k-fold cross-testing” concept across batches of varying size. Results show that blockchain batch size used for entity classification could be reduced for certain classes (Exchange, Gambling, and eWallet) as classification rates did not vary significantly with batch size; suggesting that behavioral patterns did not change significantly over time. Mixer and Market class detection, however, can be negatively affected. A deeper analysis of Mining Pool behavior showed that models trained on recent data perform better than models trained on older data, suggesting that “typical” Mining Pool behavior may be represented better by recent data. This work provides a first step towards uncovering entity behavioral changes via temporal dissection of blockchain data.
We study the liquid democracy problem, where each voter can either directly vote to a candidate or delegate his voting power to a proxy. We consider the implementation of liquid democracy on the blockchain through Ethereum smart contract and to be compatible with the realtime self-tallying property, where the contract itself can record ballots and update voting status upon receiving each voting massage. A challenge comes due to the gas fee limitation of Ethereum mainnet, that the number of instruction for processing a voting massage can not exceed a certain amount, which restrict the application scenario with respect to algorithms whose time complexity is linear to the number of voters. We propose a fast algorithm to overcome the challenge, such that i) shifts the on-chain initialization to off-chain and ii) the on-chain complexity for processing each voting massage is O(\log n), where n is the number of voters.
The objectives of the study were to verify the "Attitudes Toward Cryptocurrencies Questionnaire" and to identify predictors of attitudes toward Bitcoin. Sample: 262 participants aged 17 to 30, of which 45% were male. Methods: Associations, "Value Scale", "The Moral Foundations Questionnaire", "Money Beliefs and Behaviors Scale" by A. Furnham, and "The Baseline Confidence Scale" by L. Haff. Confirmatory factor analysis proved the three-factor structure of the questionnaire. A linear regression analysis showed that beliefs in the potential of cryptocurrency as a payment instrument are directly related to people-centered care and value of freedom, and are inversely related to sanctity; they are associated positively with confidence in the financial system and negatively with confidence in the government. Age and gender also matter. Worries about the introduction of cryptocurrency are directly related to a negative attitude to money, the value of self-confidence, age, and confidence in the financial system and government, and are inversely related to trust in people and money anxiety. Willingness to use cryptocurrency in perspective directly depends on trust in the power of money, orientation towards independence in actions, age, and gender, and is inversely dependent on confidence in the government. The data state that the intention to use cryptocurrency is directly related to the desire for financial autonomy and distrust of social institutions.
High Resolution Image Download MS PowerPoint Slide This study estimates the environmental impact of mining Bitcoin, the most well-known blockchain-based cryptocurrency, and contributes to the discussion on the technology’s supposedly large energy consumption and carbon footprint. The lack of a robust methodological framework and of accurate data on key factors determining Bitcoin’s impact have so far been the main obstacles in such an assessment. This study applied the well-established Life Cycle Assessment methodology to an in-depth analysis of drivers of past and future environmental impacts of the Bitcoin mining network. It was found that, in 2018, the Bitcoin network consumed 31.29 TWh with a carbon footprint of 17.29 MtCO 2 -eq, an estimate that is in the lower end of the range of results from previous studies. The main drivers of such impact were found to be the geographical distribution of miners and the efficiency of the mining equipment. In contrast to previous studies, it was found that the service life, production, and end-of-life of such equipment had only a minor contribution to the total impact, and that while the overall hashrate is expected to increase, the energy consumption and environmental footprint per TH mined is expected to decrease.
Micropayments are increasingly being adopted by a large number of applications. However, processing micropayments individually can be expensive, with transaction fees exceeding the payment value itself. By aggregating these small transactions into a few larger ones, and using cryptocurrencies, today's decentralized probabilistic micropayment schemes can reduce these fees. Unfortunately, existing solutions force micropayments to be issued sequentially, thus to support fast issuance rates a customer needs to create a large number of escrows, which bloats the blockchain. Moreover, these schemes incur a large computation and bandwidth overhead, which limit their applicability in large-scale systems. In this paper, we propose MicroCash, the first decentralized probabilistic framework that supports concurrent micropayments. MicroCash introduces a novel escrow setup that enables a customer to concurrently issue payment tickets at a fast rate using a single escrow. MicroCash is also cost effective because it allows for ticket exchange using only one round of communication, and it aggregates the micropayments using a lottery protocol that requires only secure hashing. Our experiments show that MicroCash can process thousands of tickets per second, which is around 1.7-4.2x times the rate of a state-of-the-art sequential micropayment system. Moreover, MicroCash supports any ticket issue rate over any period using only one escrow, while the sequential scheme would need more than 1000 escrows per second to permit high rates. This enables our system to further reduce transaction fees and data on the blockchain by around 50%.
Danilo Francati, Giuseppe Ateniese, Abdoulaye Faye, Andrea Maria Milazzo · 7 authors
The cloud changed the way we manage and store data. Today, cloud storage services offer clients an infrastructure that allows them a convenient source to store, replicate, and secure data online. However, with these new capabilities also come limitations, such as lack of transparency, limited decentralization, and challenges with privacy and security. And, as the need for more agile, private and secure data solutions continues to grow exponentially, rethinking the current structure of cloud storage is mission-critical for enterprises. By leveraging and building upon blockchain's unique attributes, including immutability, security to the data element level, distributed (no single point of failure), we have developed a solution prototype that allows data to be reliably stored while simultaneously being secured, with tamper-evident auditability, via blockchain. The result, Audita, is a flexible solution that assures data protection and solves challenges such as scalability and privacy. Audita works via an augmented blockchain network of participants that include storage-nodes and block-creators. In addition, it provides an automatic and fair challenge system to assure that data is distributed and reliably and provably stored. While the prototype is built on Quorum, the solution framework can be used with any blockchain platform. The benefit is a system that is built to grow along with the data needs of enterprises, while continuing to build the network via incentives and solving for issues such as auditing and outsourcing.
Deploying mobile edge computing (MEC) server in the mobile blockchain-enabled Internet of things (IoT) system is a promising approach to improve the system performance, however, it imposes a significant challenge on the trust of MEC server. To address this problem, we first propose an untrusted MEC proof of work scheme in mobile blockchain network where plenty of nonce hash computing demands can be offloaded to MEC server. Then, we design a nonce ordering algorithm for this scheme to provide fairer computing resource allocation for all mobile IoT devices/users. Specifically, we formulate the user's nonce selection strategy as a non-cooperative game, where the utilities of individual user are maximized in the untrusted MEC-aided mobile blockchain network. We also prove the existence of Nash equilibrium and analyze that the cooperation behavior is unsuitable for the blockchain-enabled IoT devices by using the repeated game. Finally, we design the blockchain's difficulty adjustment mechanism to ensure stable block times during a long period of time.