Yibin Xu, Yangyu Huang, Jianhua Shao, George Theodorakopoulos
Blockchain Sharding is a blockchain performance enhancement approach. By splitting a blockchain into several parallel-run committees (shards), it helps increase transaction throughput, reduce resources required, and increase reward expectation for participants. Recently, several flexible sharding methods that can tolerate up to $n/2$ Byzantine nodes ($n/2$ security level) have been proposed. However, these methods suffer from two main drawbacks. First, in a non-sharding blockchain, nodes can have different weight (power or stake) to create a consensus. So an adversary needs to control half of the overall weight of the system in order for a piece of faulty information to be accepted into the blockchain ($p/2$ security level). In blockchain sharding, all nodes carry the same weight. Thus, it is only under the assumption that the honest participants are creating as many nodes as they can that a $n/2$ security level blockchain sharding reaches the $p/2$ security level. Secondly, when some nodes leave the system, other nodes need to be reassigned, frequently, from shard to shard in order to maintain the security level of the system. In this paper, we present Multichain MWPoW, a $p/2$ security level blockchain sharding architecture that does not require honest participants to create multiple nodes and requires less node reassignment when some nodes leave the system. It combines the Multiple Winners Proof of Work consensus protocol (MWPoW) with the flexibility of $n/2$ blockchain sharding. Our experiments show that Multichain MWPoW outperforms existing blockchain sharding approaches in terms of security, transaction throughput and flexibility.
Designing an efficient difficulty control algorithm is an essential problem in Proof-of-Work (PoW) based blockchains because the network hash rate is randomly changing. This paper proposes a general difficulty control algorithm and provides insights for difficulty adjustment rules for PoW based blockchains. The proposed algorithm consists a two-layer neural network. It has low memory cost, meanwhile satisfying the fast-updating and low volatility requirements for difficulty adjustment. Real data from Ethereum are used in the simulations to prove that the proposed algorithm has better performance for the control of the block difficulty.
Tobias Sund, Claes Lööf, Simin Nadjm‐Tehrani, Mikael Asplund
One of the major areas of interest for deployment of blockchains is in the supply chain sector where decentralisation combined with immutability is expected to enhance the transparency and robustness of transaction processing drastically. In this work we contribute to a feasibility study for permissioned blockchains in the context of a major international retail company. First, we characterise the types, relationships, and volumes of events that are created in the life cycle of a product from creation to ownership transfer. We use the created event model and the data from the company operations to identify the load that such an event processing system would have to manage. Then we create a prototype based on Quorum that deals with a significant subset of the events and expose the blockchain-based prototype to variations in load to identify the maximum throughput and average transaction processing time. This system can then form the basis of understanding the bottlenecks, configuration settings and platform choices needed in future potential deployment.
This study presents conceptual research designed to assess how the sharing economy concept can be leveraged to increase the participation of commercial organisations, such as retailers and transporters, in disaster relief operations. Drawing on social exchange theory, the academic literature on the sharing economy and blockchain, as well as existing resource-sharing practices in commercial and humanitarian logistics, the study develops a theoretical framework for analysing the structure, benefits, and prerequisites of a logistics-sharing system in emergency response. In addition, it proposes to utilise the blockchain distributed ledger technology-a shared data platform that enables authenticated communication and the widespread sharing of real-time information-to facilitate interactions and enhance trust between emergency responders and commercial organisations. It is argued that using commercial logistics resources, including emergency supplies, transport capacity, and storage space, has the potential to improve the mobilisation and deployment of urgently needed relief items and augment the flexibility of emergency response.
Cryptocurrencies have recently captured the interest of the econometric literature, with several works trying to address the existence of bubbles in the price dynamics of Bitcoins and other cryptoassets. Extremely rapid price accelerations, often referred to as explosive behaviors, followed by drastic drops pose high risks to investors. From a risk management perspective, testing the explosiveness of individual cryptocurrency time series is not the only crucial issue. Investigating co-explosivity in the cryptoassets, i.e., whether explosivity in one cryptocurrency leads to explosivity in other cryptocurrencies, allows indeed to take into account possible shock propagation channels and improve the prediction of market collapses. To this aim, our paper investigates the relationships between the explosive behaviors of cryptocurrencies through a unit root testing approach.
For a decentralized and transparent society, blockchain technology has been developed. Along with this, quite a few consensus algorithms that are one of core technologies in blockchain have been proposed. Among them, we analyze a consensus algorithm called LFT2, which is used by a blockchain system, ICON. We first formulate the LFT2 consensus algorithm and then analyze safety and liveness, which can be considered as the most important properties in distributed consensus system. We prove that LFT2 satisfies safety and liveness, where a certain assumption is required to prove liveness. In addition, we compare LFT2 with two similar consensus algorithms, and from the comparison, we show that a trade-off exist among the three consensus algorithms. Finally, we simulate LFT2 to measure a liveness quality.
Blockchain-enabled Federated Learning (BFL) enables mobile devices to collaboratively train neural network models required by a Machine Learning Model Owner (MLMO) while keeping data on the mobile devices. Then, the model updates are stored in the blockchain in a decentralized and reliable manner. However, the issue of BFL is that the mobile devices have energy and CPU constraints that may reduce the system lifetime and training efficiency. The other issue is that the training latency may increase due to the blockchain mining process. To address these issues, the MLMO needs to (i) decide how much data and energy that the mobile devices use for the training and (ii) determine the block generation rate to minimize the system latency, energy consumption, and incentive cost while achieving the target accuracy for the model. Under the uncertainty of the BFL environment, it is challenging for the MLMO to determine the optimal decisions. We propose to use the Deep Reinforcement Learning (DRL) to derive the optimal decisions for the MLMO.
Blockchain-enabled Federated Learning (BFL) enables mobile devices to\ncollaboratively train neural network models required by a Machine Learning\nModel Owner (MLMO) while keeping data on the mobile devices. Then, the model\nupdates are stored in the blockchain in a decentralized and reliable manner.\nHowever, the issue of BFL is that the mobile devices have energy and CPU\nconstraints that may reduce the system lifetime and training efficiency. The\nother issue is that the training latency may increase due to the blockchain\nmining process. To address these issues, the MLMO needs to (i) decide how much\ndata and energy that the mobile devices use for the training and (ii) determine\nthe block generation rate to minimize the system latency, energy consumption,\nand incentive cost while achieving the target accuracy for the model. Under the\nuncertainty of the BFL environment, it is challenging for the MLMO to determine\nthe optimal decisions. We propose to use the Deep Reinforcement Learning (DRL)\nto derive the optimal decisions for the MLMO.\n
Abstract This article sets out a regulatory framework that facilitates blockchain cross-border financial transactions and examines how this framework can be implemented in the context of the Belt and Road Initiative (BRI). With increasing globalization and international trade, cross-border financial transactions are set to grow rapidly, especially across the Eurasian region.1 There are currently many challenges facing such transactions, from slow payment systems and different technical standards to varying legal and compliance systems.2 These challenges may be redressed by blockchain, which offers an efficient solution to the current mechanisms adopted in cross-border financial transactions. Currently, there are many experimental initiatives that seek to implement this technology to multiple fields, including remittances, clearance, and settlements.3 However, few researchers have considered in detail how this technology should be regulated in the BRI context. This article will be one of the first in-depth analyses of how laws and regulations can be applied to facilitate cross-border blockchain payments in the BRI context.
Open access
Blockchain Technology Applications and Security
E-commerce and Technology Innovations
Legal, Health, Environmental and COVID-19 Challenges
B. Saravana Balaji, P. Raja, Anand Nayyar, Sanjeevikumar Padmanaban · 5 authors
Blockchain technology is increasingly used worldwide to enhance the performance and profit of any environment through its defining characteristics, such as security, auditability, immutability, and inconspicuousness. Owing to these characteristics, the blockchain can be used in various non-financial operations of some domains, such as the Internet of Things (IoT) and distributed computing. However, implementing blockchain technology in IoT is not always a feasible solution because blockchain deployment is costly, it has limited extensibility and provides irregular bandwidth and latency. In this regard, a simple size extensible (SSE) blockchain has been proposed to provide an optimal solution for IoT environments by satisfying the needs of the IoT environment as well as ensuring end-to-end security. The implementation of the proposed blockchain develops an overlay network to obtain a distributed environment where the blockchain is handled by the resources present therein. Two novel algorithms were introduced into the proposed system to minimize the irregularity and latency on one hand, and to maximize the throughput of the system on the other. The shared-time depending agreement algorithm (STD) minimizes the irregularity in the extraction operation and latency. The other, the shared throughput administration algorithm (STA) justifies the overall collection of the transmission load in the network and maintains the performance of the blockchain. The proposed system was applied to smart home IoT appliances to test the performance of the proposed system. The experimental results show that the proposed blockchain system minimizes nearly 70% of the data irregularity, latency, and furthermore, 30% of the blockchain extensibility is maximized as compared to the existing systems.
To improve transaction rates, many cryptocurrencies have implemented so-called ''Layer-2'' transaction protocols, where payments are routed across networks of private payment channels. However, for a given transaction, not every network state provides a feasible route to perform the payment; in this case, the transaction must be put on the public ledger. The payment channel network thus multiplies the transaction rate of the overall system; the less frequently it fails, the higher the multiplier. We build on earlier work on credit networks and show that this network liquidity problem is connected to the combinatorics of graphical matroids. Earlier work could only analyze the (unnatural) scenario where transactions had discrete sizes. Superficially, it might seem like the continuous case would be harder to examine. However, removing this assumption lets us make progress in two important directions. First, we give a partial answer to the ``monotonicity conjecture'' that previous work left open. This conjecture asks that the network's performance not degrade as capacity on any edge increases. And second, we construct here a network state sampling procedure with much faster asymptotic performance than off-the-shelf Markov chains ($O(\vert E\vert β(\vert E\vert))$, where $β(x)$ is the complexity of solving a linear program on $x$ constraints.) We obtain our results by mapping the underlying graphs to convex bodies and then showing that the liquidity and sampling problems reduce to bounding and computing the volumes of these bodies. The transformation relies crucially on the combinatorial properties of the underlying graphic matroid, as do the proofs of monotonicity and fast sampling.
Arun Kumar Sangaiah, Hongguang Xiao, Wang Jin, Jingjing Tan · 6 authors
The development of blockchain technology is very rapidly. As a decentralized distributed technology, the blockchain has become one of the most promising Internet applications, and its application in the power balance trading platform has also received extensive attention. In view of the information asymmetry between the trading center and the margin trading users in the power balance trading platform, it is difficult to guarantee the fairness of the transaction and affect the actual income of the production consumers. First, we analyze the trading mechanism of the power surplus market.Then we designed a smart contract for multi-party bidding power resources based on blockchain technology, and achieved the decentralized power trading decision to ensure the information is symmetric and fair.At the same time, the credibility model is established by analyzing the user's recent transaction records, and we design a corresponding punishment mechanism to strengthen the constraint on the execution of offline point-to-point power transactions.
Long before the creation of blockchain platforms, the rise of personal computing and Internet connectivity brought with it a digital, online dimension of the material world, leading to the socio-technical construct known as ‘digital identity’. After the online discussion boards and emailing lists of the early 90s, individuals started socializing via the Internet more predominantly using social networks. One specific type of platform links this online socializing and transacting to blockchain-based spaces: dark web marketplaces. Identified as second-generation cryptocommunities, dark web marketplaces deployed cryptography for the use of pseudonymous identity, for communication, but also currency. This paper explores two questions in this fascinating space: what was the role of identity on the Silk Road, and what governance lessons can be drawn from this illustration for the purpose of applying them to more recent cybercommunities such as Ethereum? The paper is structured as follows. The first part describes the Silk Road and sketches its essential characteristics. The second part looks at how individuals could become platform users on the Silk Road, by analyzing the contractual relationship between the Silk Road and an individual user based on the rights and obligations enshrined in the Silk Road Terms of Service (ToS). The third part critically reflects on arbitrariness as the main pitfall arising out of the private regulatory framework created by the Silk Road, and contributes to existing narratives surrounding the regulatory nature of code by proposing a code-as-procedure perspective for analyzing this regulatory framework. Part four concludes.
The transformative turn of innovation policy has resulted in calls for a more entrepreneurial and directional role of the state. However, the multiple roles that the state might play remains underexplored. This paper studies the embedded role of the state in four distinct modes of governance of socio-technical systems. Using a three-pillar analytical model, the paper examines four illustrative cases: cryptocurrencies, smart cities, automated vehicles, and nuclear power. The paper identifies 13 different roles of the state: observer, warner, mitigator, opportunist, facilitator, lead-user, enabler of societal engagement, gatekeeper, promoter, moderator, initiator, guarantor and watchdog. The conceptualization of these roles serves to understand that the transformative agency of the state is leveraged/constrained by the modes of governance, and that it is also ultimately exercised through specific mixes of roles.
Purpose Blockchain is expected to have a significant impact on Systems of Innovation as the new General Purpose Technology. The purpose of this study is to investigate how Blockchain can revolutionise the Systems of Innovation by investigating its overall structure, actors and relationships. Design/methodology/approach This study used the systematic mapping method to explore and integrate the Blockchain and Systems of Innovation literature for the creation of a new conceptual model of Blockchain-enabled Systems of Innovation. In that scope, 37 Blockchain-related and 32 Systems of Innovation-related papers, besides two major books in the field of Blockchain, have been reviewed and then integrated based on the Systems Thinking approach. Findings The key findings for Blockchain-enabled Systems of Innovation are that there is (1) an increased distribution of networks and collaborations, (2) increased trust through the use of reputation systems, (3) an emerging new nature of platform characteristics, (4) a democratisation of entrepreneurship by the new funding landscape and (5) an increased significance of technological drivers, such as energy. Research limitations/implications The study shows new Systems of Innovation-related research implications. Accordingly, a new type of actor, relationship and attribute has been introduced where the boundaries of the role definitions are blurred and more distributed. This is where larger organisations can expect to lose their central position. The different types of actors are replaced by a network of actors as a result of the distributed new Blockchain-based system. The threshold for the Bottom of the Pyramid is expected to be reduced, leading to a more democratised innovation system. Practical Implications Blockchain appears to reduce the effects of distrust in collaborative innovation practices with its consensus mechanisms and the new Blockchain-enabled Systems of Innovation is expected to revolutionise the interactions in the future. Originality/value There are very few studies that have been found to integrate innovation management practices with Blockchain. This is the first Blockchain-based Systems of Innovation study enabling the fundamental revision of its structure, types of relationships and actors.
of-ethereum-92b543594e84 [https://perma.cc/BWZ2-6PJE].2 In terms of reporting and withholding, the same problems arise in the cash economy, which is responsible for a significant amount of noncompliance with tax laws around the world.But in terms of the identification of reportable transactions, there may be base defining issues.The
With the rapid development of industrial internet of thing (IIoT), the distributed topology of IIoT and resource constraints of edge computing conduct new challenges to traditional data storage, transmission, and security protection. A distributed trust and allocated ledger of blockchain technology are suitable for the distributed IIoT, which also becomes an effective method for edge computing applications. This paper proposes a resource constrained Layered Lightweight Blockchain Framework (LLBF) and implementation mechanism. The framework consists of a resource constrained layer (RCL) and a resource extended layer (REL) blockchain used in IIoT. We redesign the block structure and size to suit to IIoT edge computing devices. A lightweight consensus algorithm and a dynamic trust right algorithm is developed to improve the throughput of blockchain and reduce the number of transactions validated in new blocks respectively. Through a high throughput management to guarantee the transaction load balance of blockchain. Finally, we conducted kinds of blockchain simulation and performance experiments, the outcome indicated that the method have a good performance in IIoT edge application.
The purpose of the study is to identify and explore different applications of blockchain technology in supply chain management and suggest a framework for their analysis. The study addresses researchers' conflicting opinions regarding the hype of blockchain and clarifies which minor applications are hyped and which are currently more applicable. That helps supply chain practitioners appraise the different applications of blockchains before it is too late to revise a decision regarding their use. The framework was developed based on a systematic literature review of blockchain-related articles, and it was examined with semi-structured interviews with four companies that applied the technology. Findings from the study suggested that traceability and supply chain finance seemed to be the most applicable applications of blockchain technology in supply chain management. But, light was also shed on other applications such as: compliance with standards, supply chain integration and digitalization of the transactions. This study was restricted by the availability of applied cases, as blockchain remains an emerging technology. Therefore, this study cannot be considered a case research, but a literature review followed by a limited number of interviews. However, the study resulted in a conceptual framework that forms the basis for further exploratory studies with more empirical data.
Thays A. Oliveira, Miquel Oliver, Helena Ramalhinho
The way citizens interact with cities affects overall life quality. Their participation in social decisions is of paramount importance for helping on public decisions that affect governance, regulation and education. This interaction has the potential of being boosted within the scope of smart and digital cities, especially by recent advances in blockchain technology. This work introduces insights about how smart cities’ concepts and innovative technologies can help society to face daily challenges for improving citizens’ awareness. Digital technologies are able to drive social and economic development by employing Information and Communication Technology (ICT) to promote innovation. In this context, e-governance, in conjunction with disruptive concepts such as blockchain, is showing up as a fundamental tool for a decentralized democracy. This study reviews, discusses, raises open points and presents suggestions towards an efficient, transparent and sustainable use of technology, applied to future cities.
Chad Albrecht, Steven R. Hawkins, Kristopher McKay Duffin
Cryptocurrency, and especially Bitcoin, has struggled to gain recognition as a legitimate currency from governments, financial institutions, and consumers. This has occurred because many analysts and consumers believe that Bitcoin is not a stable and consistent store of value, a unit of measurement, or a medium of exchange. One way to overcome this challenge is for Bitcoin to be used as both a currency and store of value by a greater percentage of the world’s population. This paper seeks to identify how a change in Bitcoin’s monetary measurement (or denomination) can more easily facilitate Bitcoin transactions to increase its use. Specifically, we posit that applying whole number bias theory, from the cognitive psychology and mathematics fields, to Bitcoin’s unit of measurement will allow the value of Bitcoin to be referenced in smaller and easier tounderstand units with fewer numbers after the decimal point—such as the “Bit” or the “Satoshi.” In the process, the use of Bitcoin will include more whole numbers and allow the general public to more easily assign value to Bitcoin in day-to-day transactions.
Muhammed Siraj, Mohd Izuan Hafez Ninggal, Nur Izura Udzir, Muhammad Daniel Hafiz Abdullah · 5 authors
Sensitive records stored in the cloud such as healthcare records, private conversation and credit card information are targets of hackers and privacy abuse. Current information and record management systems have difficulties achieving privacy protection of such sensitive records in a secure, transparent, decentralized and trustless environment. The Blockchain technology is a nascent and a promising technology that facilitates data sharing and access in a secure, decentralized and trustless environment. The technology enables the use of smart contracts that can be leveraged to complement existing traditional systems to achieve security objectives that were never possible before. In this paper, we propose a framework based on Blockchain technology to enable privacy-preservation in a secured, decentralized, transparent and trustless environment. We name our framework SmartCoAuth. It is based on Ethereum Smart Contract functions as the secure, decentralized, transparent authentication and authorization mechanism in the framework. It also enables tamper-proof auditing of access to the protected records. We analysed how SmartCoAuth could be integrated into a cloud application to provide reliable privacy-preservation among stakeholders of healthcare records stored in the cloud. The proposed framework provides a satisfactory level of data utility and privacy preservation.
The article covers the possibilities of comprehensive use of identification technologies and Distributed Ledger Technology (DLT) for increasing the efficiency of electronic services provided through multi-purpose student cards. The main advantages and disadvantages of the existing intellectual document emission systems in the Belarusian education system are assessed, including: centralized (the “Student Card” project) and decentralized (the electronic student card) ones. The proposal to use the DLT-model for issuing multi-purpose electronic student cards combined with bank payment cards has been grounded. Such model makes it possible to implement new functional capabilities when providing electronic services and has a number of advantages over the existing systems of electronic student documents issuance. The article describes how Public Blockchain and Private Blockchain can be used to issue and control intellectual documents, to accelerate the development of the electronic services provided through Smart Contract, and how the Smart Contract technology can be used to promote fair competition among electronic services providers. The methodology of evaluating the electronic services provider rating basing on the weighting factor of “usefulness” or “being in demand” is proposed. The article provides information on the expected effects of the proposed DLT-model implementation, obtained through the comprehensive use of identification technologies and distributed ledger technology.
Open access
Economic and Technological Systems Analysis
Digital Transformation in Law
Digitalization and Economic Development in Agriculture