Money’s materiality produces an ontological conundrum for social theory: should the analysis of money foreground the objects used as money, or the abstract relations that underpin it? Provoked by the emergence of cryptocurrencies, this paper develops a conceptualization of money as a technological and social infrastructure which directly addresses this theoretical impasse. Cryptocurrencies’ sole form of material existence coincides with their underpinning infrastructure of records, accounting and payments. In the past decade, cryptocurrencies have skyrocketed in number, and they have been applied to a host of use cases. This paper focuses on cross-border payments through the example of the fintech company Ripple, the cryptocurrency XRP, and the design of the XRP Ledger. Combining literatures from the social theory of money, science and technology studies and new materialisms, this article develops steps towards an ecological conceptualization of money infrastructures. Infrastructures, understood ecologically, include devices, active forms, and imaginaries in seamless webs of mutual relations of co-evolution. These ecologies are always potentially prone to slippage, dissolution, disassembling, reassembling and reappropriation, dependence, and competition.
The challenge of automatically determining the correctness of test executions is referred to as the test oracle problem and is one of the key remaining issues for automated testing. The goal in this paper is to solve the test oracle problem in a way that is general, scalable and accurate. To achieve this, we use supervised learning over test execution traces. We label a small fraction of the execution traces with their verdict of pass or fail. We use the labelled traces to train a neural network (NN) model to learn to distinguish runtime patterns for passing versus failing executions for a given program. Our approach for building this NN model involves the following steps, 1. Instrument the program to record execution traces as sequences of method invocations and global state, 2. Label a small fraction of the execution traces with their verdicts, 3. Designing a NN component that embeds information in execution traces to fixed length vectors, 4. Design a NN model that uses the trace information for classification, 5. Evaluate the inferred classification model on unseen execution traces from the program. We evaluate our approach using case studies from different application domains: 1. Module from Ethereum Blockchain, 2. Module from PyTorch deep learning framework, 3. Microsoft SEAL encryption library components, 4. Sed stream editor, 5. Value pointer library and 6. Nine network protocols from Linux packet identifier, L7-Filter. We found the classification models for all subject programs resulted in high precision, recall and specificity, over 95%, while only training with an average 9% of the total traces. Our experiments show that the proposed neural network model is highly effective as a test oracle and is able to learn runtime patterns to distinguish passing and failing test executions for systems and tests from different application domains.
Marco Valeri, Rosario Fondacaro, Cinzia De Angelis, Andrea Barella
This paper aims to evaluate where the application of new fintech solutions like blockchain and cryptocurrencies can be considered as an opportunity to build bridges between Islamic and western culture in order to create a trusted money transfer with low commission and a big transparency and trust. The research question is: Can an Hawala systems based on DLT technologies be considered compliant both with anti-money laundry regulations and with Sharia values? This is a conceptual paper relying upon an understanding of the literature in the fields of technology, sociology, anthropology, criminology and regulatory, as applied to the topic of Islamic practice known as Hawala and emerging new disruptive technologies like Distributed Ledger Technology. The research has been conducted by a literature reviewing on Scopus data base by searching the following keywords: Islamic finance, cryptocurrencies, hawala, stablecoin, globalcoin, money laundering, blockchain. The searching period was set on the last 10 years. The paper discusses some scenarios to define new fintech Hawala system in an evolving scenario of cryptocurrencies, social network commitments and different type of blockchain where it can be digitally transformed by using new fintech technologies while became compliance with anti-money laundering regulations with the respect of Islamic values. As practical implications, this paper could help to encourage researcher and entrepreneurs to evaluate and propose a digital transformation approach with the aim to maintain ancient tradition and, at the same time, apply new technology that improve the life of citizens. As social implications this paper expands upon the understanding of how new fintech solution can be easily be integrated in the real life by using common devices like a mobile phone to be used as wallet for the daily expenses and to receive money from relatives from western countries. The originality/value of this paper is that it covers the literature gap in the field of new fintech solutions applied to Islamic finance by providing a likely proposal by integrating popular tradition, regulations and new technologies. The research limitations and implications are related to that this is a conceptual paper; case studies haven’t been treated, so it is not able to say definitively if the outcomes discussed can be defined as an effective solution and can be developed in the real global society, in a future prospective it’ll be possible to continue to make researches in this field of application with fintech technologies and Islamic Finance.
Recent analysis of Blockchain use has highlighted considerable potential productivity gains arising from lower transaction costs between buyers and sellers of goods. This has been shown by recent examples of Blockchain use in the Australian grains sector. In this paper, we have further developed and quantified this concept of productivity gain by undertaking several illustrative scenarios using a general equilibrium model of the global economy. Our analysis indicates that an assumed modest growth (five per cent) in productivity due to Blockchain use in the grains sector could raise output by eight per cent over the medium term. If this is accompanied by Blockchain use in the Australian finance sector, grains output could reach ten per cent. This reflects the effect of reduction in transaction costs due to the use of Blockchain technology as a “distributed ledger technology” in grain trading. Further, it is anticipated that the wider effects of Blockchain‐driven productivity enhancement of the Australian finance sector could contribute to approximately 2.5 per cent increase in GDP in the medium term, relative to what would otherwise be.
Edgar González Fernández, Guillermo Morales-Luna, Feliú Sagols
Current requirements for ensuring data exchange over the internet to fight against security breaches have to consider new cryptographic attacks. The most recent advances in cryptanalysis are boosted by quantum computers, which are able to break common cryptographic primitives. This makes evident the need for developing further communication protocols to secure sensitive data. Zero-knowledge proof systems have been around for a while and have been considered for providing authentication and identification services, but it has only been in recent times that its popularity has risen due to novel applications in blockchain technology, Internet of Things, and cloud storage, among others. A new zero-knowledge proof system is presented, which bases its security in two main problems, known to be resistant, up to now, against quantum attacks: the graph isomorphism problem and the isomorphism of polynomials problem.
Blockchains such as the bitcoin blockchain depend on reaching a global consensus on the distributed ledger; therefore, they suffer from well know scalability problems. This paper proposes an algorithm that avoids double-spending in the short term with just O(√n) messages; each node receiving money off-chain performs the due diligence of consulting k√n random nodes to check if any of them is aware of double-spending. Two nodes receiving double-spent money will in this way consult at least one common node with very high probability, due to the ‘birthday paradox’, and any common honest node consulted will detect the fraud. Since the velocity of money in the real world has coins circulating through at most a few wallets per day, the size of the due diligence communication is small in the short term. This `k-root-n’ algorithm is suitable for an environment with synchronous or asynchronous (but with fairly low latency) communication and with Byzantine faults. The presented k-root-n algorithm should be practical to avoid double-spending with arbitrarily high probability, while feasibly coping with the throughput of all world commerce. It is resistant to Sybil attacks even beyond 50% of nodes. In the long term, the k-root-n algorithm is less efficient. Therefore, it should preferably be used as a complement and not a replacement to a global distributed ledger technology.
Murat Ozer, Said Varlioglu, Bilal Gonen, Mehmet F. Bastug
The availability of sophisticated technologies and methods of perpetrating criminogenic activities in the cyberspace is a pertinent societal problem. Darknet is an encrypted network technology that uses the internet infrastructure and can only be accessed using special network configuration and software tools to access its contents which are not indexed by search engines. Over the years darknets traditionally are used for criminogenic activities and famously acclaimed to promote cybercrime, procurements of illegal drugs, arms deals, and cryptocurrency markets. In countries with oppressive regimes, censorship of digital communications, and strict policies prompted journalists and freedom fighters to seek freedom using darknet technologies anonymously while others simply exploit it for illegal activities. Recently, MIT's Lincoln Laboratory of Artificial Intelligence augmented a tool that can be used to expose illegal activities behind the darknet. We studied relevant literature reviews to help researchers to better understand the darknet technologies, identify future areas of research on the darknet and ultimately to optimize how data-driven insights can be utilized to support governmental agencies in unraveling the depths of darknet technologies. This paper focuses on the use of the internet for crimes, deanonymization of TOR-services, darknet a new digital street for illicit drugs, research questions and hypothesis to guide researchers in further studies. Finally, in this study, we propose a model to examine and investigate anonymous online illicit markets.
Said Varlioglu, Bilal Gonen, Murat Ozer, Mehmet F. Bastug
Cryptojacking is the exploitation of victims' computer resources to mine for cryptocurrency using malicious scripts. It has become popular after 2017 when attackers started to exploit legal mining scripts, especially Coinhive scripts. Coinhive was actually a legal mining service that provided scripts and servers for in-browser mining activities. Nevertheless, over 10 million web users had been victims every month before the Coinhive shutdown that happened in Mar 2019. This paper explores the new era of the cryptojacking world after Coinhive discontinued its service. We aimed to see whether and how attackers continue cryptojacking, generate new malicious scripts, and developed new methods. We used a capable cryptojacking detector named CMTracker that proposed by Hong et al. in 2018. We automatically and manually examined 2770 websites that had been detected by CMTracker before the Coinhive shutdown. The results revealed that 99\% of sites no longer continue cryptojacking. 1\% of websites still run 8 unique mining scripts. By tracking these mining scripts, we detected 632 unique cryptojacking websites. Moreover, open-source investigations (OSINT) demonstrated that attackers still use the same methods. Therefore, we listed the typical patterns of cryptojacking. We concluded that cryptojacking is not dead after the Coinhive shutdown. It is still alive, but not as attractive as it used to be.
Yinqiu Liu, Kai Qian, Jianli Chen, Kun Wang · 5 authors
As an emerging technology, blockchain has achieved great success in numerous application scenarios, from intelligent healthcare to smart cities. However, a long-standing bottleneck hindering its further development is the massive resource consumption attributed to the distributed storage and computation methods. This makes blockchain suffer from insufficient performance and poor scalability. Here, we analyze the recent blockchain techniques and demonstrate that the potential of widely-adopted consensus-based scaling is seriously limited, especially in the current era when Moore's law-based hardware scaling is about to end. We achieve this by developing an open-source benchmarking tool, called Prism, for investigating the key factors causing low resource efficiency and then discuss various topology and hardware innovations which could help to scale up blockchain. To the best of our knowledge, this is the first in-depth study that explores the next-generation scaling strategies by conducting large-scale and comprehensive benchmarking.
Jedsada tipmontian, Jaime Castellanos Alcover, M. Rajmohan
Today’s food supply chain is incredibly complex and imposes enormous challenges across the Globe. Products are transported through multimodal transportation internationally, comprising of combination of ship, rail, truck and flight modes etc. The supply chain under multistage network poses more quality related issues. Hence, blockchain technology helps to enhance food safety and quality in the logistics process. This, when coupled with the existing traceability system can create more agile value chain and closer customer relationship across regions. Though, Thailand is a leading food exporter, it lacks in implementation of blockchain technology. The objective of this study is to analyse the impact of blockchain technology adoption for safe food supply chain management through System Dynamics (SD) approach from management perspectives in Thailand. The preliminary survey and discussion were carried out with the participants from food expert firms, and causal loop diagrams and stock and flow diagrams were developed and validated. The trade-off, challenges and opportunities of applying block chain technology on the global food value supply chain has been discussed throughout the system dynamics model. The major contribution of this work is in providing insight into some of the main dimensions of block chain technology and its implications for global food value chain performance improvements.
What drives growth becomes cancerous when it goes beyond limits. Contrary to this common sense, today, consumerism drives our economies and feeds our appetite for ever-growing wants. As a result, we are damaging our ecosystems and risking our very existence on Earth. Though too late, various efforts are promoted by governments and driven by industries to rapidly decarbonize our energy systems and sustainably consume and recycle raw materials. We have discussed two ongoing projects in the domain of energy transition and circular economy. The first one transforms industrial carbon emissions into green fuels and the second one helps in efficient and sustainable segregation and recycling of plastic waste using multi-sensor-driven AI and blockchain tools. These examples demonstrate how circular economy and energy transitions complement each other in the battle against climate change and pollution.
Blockchain has emerged as a promising technology that can guarantee data consistency and integrity among distributed participants. It has been used in many applications of the Internet of Things (IoT). However, since IoT applications often introduce a massive number of devices into blockchain systems, the efficiency of the blockchain becomes a serious problem. In this article, we analyze the key factors affecting the efficiency of blockchain. Unlike most existing solutions that handle this from the computing perspective, we consider the problem from the communication perspective. In particular, we propose a coordinated satellite-terrestrial network to create efficient blockchains. We also derive a network scheduling strategy for the proposed architecture. Simulation results demonstrate that the proposed system can support blockchains for higher efficiency. Moreover, several open research issues and design challenges will be discussed.
Jawad Ali, Ahmad Shahrafidz Khalid, Eiad Yafi, Shahrulniza Musa · 5 authors
Internet of Things (IoT) occupies a vital aspect of our everyday lives. IoT networks composed of smart-devices which communicate and transfer the information without the physical intervention of humans. Due to such proliferation and autonomous nature of IoT systems make these devices threatened and prone to a severe kind of threats. In this paper, we introduces a behavior capturing, and verification procedures in blockchain supported smart-IoT systems that can be able to show the trust-level confidence to outside networks. We defined a custom \emph{Behavior Monitor} and implement on a selected node that can extract the activity of each device and analyzes the behavior using deep machine learning strategy. Besides, we deploy Trusted Execution Technology (TEE) which can be used to provide a secure execution environment (enclave) for sensitive application code and data on the blockchain. Finally, in the evaluation phase we analyze various IoT devices data that is infected by Mirai attack. The evaluation results show the strength of our proposed method in terms of accuracy and time required for detection.
Anuraag A Vazirani, Odhran O’Donoghue, David Brindley, Edward Meinert
The lack of interoperability in Britain's medical records systems precludes the realisation of benefits generated by increased spending elsewhere in healthcare. Growing concerns regarding the security of online medical data following breaches, and regarding regulations governing data ownership, mandate strict parameters in the development of efficient methods to administrate medical records. Furthermore, consideration must be placed on the rise of connected devices, which vastly increase the amount of data that can be collected in order to improve a patient's long-term health outcomes. Increasing numbers of healthcare systems are developing Blockchain-based systems to manage medical data. A Blockchain is a decentralised, continuously growing online ledger of records, validated by members of the network. Traditionally used to manage cryptocurrency records, distributed ledger technology can be applied to various aspects of healthcare. In this manuscript, we focus on how Electronic Medical Records in particular can be managed by Blockchain, and how the introduction of this novel technology can create a more efficient and interoperable infrastructure to manage records that leads to improved healthcare outcomes, while maintaining patient data ownership and without compromising privacy or security of sensitive data.
Vasilios Mavroudis, Karl Wüst, Aritra Dhar, Kari Kostiainen · 5 authors
Permissionless blockchains offer many advantages but also have significant limitations including high latency. This prevents their use in important scenarios such as retail payments, where merchants should approve payments fast. Prior works have attempted to mitigate this problem by moving transactions off the chain. However, such Layer-2 solutions have their own problems: payment channels require a separate deposit towards each merchant and thus significant locked-in funds from customers; payment hubs require very large operator deposits that depend on the number of customers; and side-chains require trusted validators. In this paper, we propose Snappy, a novel solution that enables recipients, like merchants, to safely accept fast payments. In Snappy, all payments are on the chain, while small customer collaterals and moderate merchant collaterals act as payment guarantees. Besides receiving payments, merchants also act as statekeepers who collectively track and approve incoming payments using majority voting. In case of a double-spending attack, the victim merchant can recover lost funds either from the collateral of the malicious customer or a colluding statekeeper (merchant). Snappy overcomes the main problems of previous solutions: a single customer collateral can be used to shop with many merchants; merchant collaterals are independent of the number of customers; and validators do not have to be trusted. Our Ethereum prototype shows that safe, fast (<2 seconds) and cheap payments are possible on existing blockchains.
The recent proliferation of Electronic Commerce (E-commerce) has been further escalated by multifaceted emerging payment solutions such as cryptocurrencies, mobile, peer-to-peer (P2P) and social media payment platforms. While these technological advancements are gaining tremendous popularity, mostly for their ease of use, various impediments such as security and privacy concerns, societal and cultural norms etc. forbear the users' adoption trends to some extents. This article examines the current status of the social media payment platforms as well as the projection of future adoption trends. Our research underlines the motivations and obstacles to the adoption of social media platforms.
The interoperability across multiple blockchains would play a critical role in future blockchain-based data management paradigm. Existing techniques either work only for two blockchains or requires a centralized component to govern the cross-blockchain transaction execution, neither of which would meet the scalability requirement. This paper proposes a new distributed commit protocol, namely \textit{cross-blockchain transaction} (CBT), for conducting transactions across an arbitrary number of blockchains without any centralized component. The key idea of CBT is to extend the two-phase commit protocol with a heartbeat mechanism to ensure the liveness of CBT without introducing additional nodes or blockchains. We have implemented CBT and compared it to the state-of-the-art protocols, demonstrating CBT's low overhead (3.6\% between two blockchains, less than $1\%$ among 32 or more blockchains) and high scalability (linear scalability on up to 64-blockchain transactions). In addition, we developed a graphic user interface for users to virtually monitor the status of the cross-blockchain transactions.
In the blockchain, the consensus mechanism plays a key role in maintaining the security and legitimation of contents recorded in the blocks. Various blockchain consensus mechanisms have been proposed. However, there is no technical analysis and comparison as a guideline to determine which type of consensus mechanism should be adopted in a specific scenario/application. To this end, this work investigates three mainstream consensus mechanisms in the blockchain, namely, Proof of Work (PoW), Proof of Stake (PoS), and Direct Acyclic Graph (DAG), and identifies their performances in terms of the average time to generate a new block, the confirmation delay, the Transaction Per Second (TPS) and the confirmation failure probability. The results show that the consensus process is affected by both network resource (computation power/coin age, buffer size) and network load conditions. In addition, it shows that PoW and PoS are more sensitive to the change of network resource while DAG is more sensitive to network load conditions.
In this paper, we show a security engineering process based on a formal notion of refinement fully formalized in the proof assistant Isabelle. This Refinement-Risk Cycle focuses on attack analysis and security refinement supported by interactive theorem proving. Since we use a fully formalized model of infrastructures with actors and policies we can support a novel way of formal security refinement for system specifications. This formal process is built practically as an extension to the Isabelle Infrastructure framework with attack trees. We define a formal notion of refinement on infrastructure models. Thanks to the formal foundation of Kripke structures and branching time temporal logic in the Isabelle Infrastructure framework, these stepwise transformations can be interleaved with attack tree analysis thus providing a fully formal security engineering framework. The process is illustrated on an IoT healthcare case study introducing GDPR requirements and blockchain.
This paper studies how to forecast daily closing price series of Bitcoin,\nusing data on prices and volumes of prior days. Bitcoin price behaviour is\nstill largely unexplored, presenting new opportunities. We compared our results\nwith two modern works on Bitcoin prices forecasting and with a well-known\nrecent paper that uses Intel, National Bank shares and Microsoft daily NASDAQ\nclosing prices spanning a 3-year interval. We followed different approaches in\nparallel, implementing both statistical techniques and machine learning\nalgorithms. The SLR model for univariate series forecast uses only closing\nprices, whereas the MLR model for multivariate series uses both price and\nvolume data. We applied the ADF -Test to these series, which resulted to be\nindistinguishable from a random walk. We also used two artificial neural\nnetworks: MLP and LSTM. We then partitioned the dataset into shorter sequences,\nrepresenting different price regimes, obtaining best result using more than one\nprevious price, thus confirming our regime hypothesis. All the models were\nevaluated in terms of MAPE and relativeRMSE. They performed well, and were\noverall better than those obtained in the benchmarks. Based on the results, it\nwas possible to demonstrate the efficacy of the proposed methodology and its\ncontribution to the state-of-the-art.\n
The paper presents an approach of the blockchain and smart contracts utilization for dynamic robot coalition creation. The coalition is forming for solving complex tasks in industry applications that requires sequential united actions from the several robots. The main idea is that the process is split into two stages: scheduling and dynamic execution. On the scheduling stage, the coalition is defined based on the correlation of existing tasks and robot equipment, and the execution plan is formed and stored in smart contracts. The second stage is the plan execution. During this stage, smart contract controls how each robot solves its sub-task and whether it solves the sub-task due to the planned moment of time. In case of any deviation from the plan, smart contacts will provide a solution for returning to the plan or for changing the coalition composition with new robots and an execution plan. The prototype for execution control system has been developed based on the Hyperledger Fabric platform.
Ying Chen, Paolo Giudici, Branka Hadji Misheva, Simon Trimborn
We aim to understand the dynamics of Bitcoin blockchain trading volumes and, specifically, how different trading groups, in different geographic areas, interact with each other. To achieve this aim, we propose an extended Vector Autoregressive model, aimed at explaining the evolution of trading volumes, both in time and in space. The extension is based on network models, which improve pure autoregressive models, introducing a contemporaneous contagion component that describes contagion effects between trading volumes. Our empirical findings show that transactions activities in bitcoins is dominated by groups of network participants in Europe and in the United States, consistent with the expectation that market interactions primarily take place in developed economies.