Location-Based Services (LBSs) are essential in many application contexts like ride-sharing or navigation apps. There are cases where users could gain an advantage by submitting fake locations. The problem faced in this paper concerns the possibility that the geographic location declared by a user is not the actual location in which the user is placed. Some solutions are based on centralized or distributed verification in the literature, and other solutions are based on witnesses or infrastructure. In this paper, we highlight the limitations of such approaches and propose a new scheme that exploits signals coming from satellites to provide trustworthy location proofs, also respecting users' privacy. The proposed approach is decentralized because location proofs are stored by users in a suitably-encrypted way, and a blockchain is adopted to guarantee data integrity and authenticity. We show that the proposed approach overcomes the state of the art through a detailed analysis.
Federico Cernera, Massimo La Morgia, Alessandro Mei, Francesco Sassi
In this work, we perform a longitudinal analysis of the BNB Smart Chain and Ethereum blockchain from their inception to March 2022. We study the ecosystem of the tokens and liquidity pools, highlighting analogies and differences between the two blockchains. We discover that about 60% of tokens are active for less than one day. Moreover, we find that 1% of addresses create an anomalous number of tokens (between 20% and 25%). We discover that these tokens are used as disposable tokens to perform a particular type of rug pull, which we call 1-day rug pull. We quantify the presence of this operation on both blockchains discovering its prevalence on the BNB Smart Chain. We estimate that 1-day rug pulls generated $240 million in profits. Finally, we present sniper bots, a new kind of trader bot involved in these activities, and we detect their presence and quantify their activity in the rug pull operations.
Ziqiao Ao, Lin William Cong, Gergely Horváth, Luyao Zhang
Decentralized finance (DeFi) has the potential to disrupt centralized finance by validating peer-to-peer transactions through tamper-proof smart contracts, thus significantly lowering the transaction cost charged by financial intermediaries. However, the actual realization of peer-to-peer transactions and the levels and effects of decentralization are largely unknown. Our research pioneers a blockchain network study that applies social network analysis to measure the level, dynamics, and impacts of decentralization in DeFi token transactions on the Ethereum blockchain. First, we find a significant core-periphery structure in the AAVE token transaction network where the cores include the two largest centralized crypto exchanges. Second, we provide evidence that multiple network features consistently characterize decentralization dynamics. Finally, we document that a more decentralized network significantly predicts a higher return and lower volatility of the decentralized market of AAVE tokens on the Ethereum blockchain. We point out that our approach is seminal for inspiring future extensions related to the facets of application scenarios, research questions, and methodologies on the mechanics of blockchain decentralization.
Abstract In recent years, With the rapid development of blockchain technol- ogy, there has been an increased interest in solving various opera- tional challenges. For the e-voting system at present, voter’s privacy, immutability of votes and third party dependency are major issues. These issues can very well be solved by blockchain technology. In this paper, we have proposed a decentralized framework for e-voting based on blockchain technology that contributes significantly to the implementation paradigm. We have implemented it on the Ethereum platform and developed a fully functional smart contract to store and validate votes. The research provides deep insight into the design of smart contract transactions in an e-voting system from a computa- tional cost perspective. In order to authenticate the voters, We have done voter verification in two phases. In the first phase, the voter reg- isters through a secure code, whose(code) Keccak-256 hash is stored on the blockchain, and in the second phase, the voter is verified by the managing authority. Based on the literature review, we found a lack of standardization for blockchain-based e-voting systems. So we have tried to fill this gap of standardization. In addition, we have also inspectedour model against various security attacks and found that our model is robust against double-spend attack, re-entrancy attack, DDoS etc.
Shantanu Pal, Ambrose Hill, Tahiry Rabehaja, Michael Hitchens
There has been considerable advancement in the use of blockchain for trust management in large-scale dynamic systems. In such systems, blockchain is mainly used to store the trust score or trust-related information of interactions among the various entities. However, present trust management archi-tectures using blockchain lack verifiable interactions among the entities on which the trust score is calculated. In this paper, we propose a blockchain-based trust management framework that allows independent trust providers to implement different trust metrics on a common set of trust evidence and provide individual trust value. We employ geo-location as proof of interaction. Some of the existing proposals rely upon geo-location data, but they do not support trust calculation by multiple trust providers. Instead, they can only support a centralised system. Our proposed architecture does not depend upon a single centralised third-party entity to ensure trusted interactions. Our architecture is supported by provable interactions that can easily be verified using blockchain. Therefore, it allows a high degree of confidence in trust management by ensuring the actual interactions between the entities. We provide a detailed design and development of the architecture using real-world use case examples. The proof of prototype was implemented on the Ethereum blockchain platform. Experimental results demonstrate that the employment of independent trust providers adequately provides a high degree of trust scores and that the proposed architecture can be used in a real-world environment.
In this research, we provided an answer to a very important trading question, what is the optimal number of technical tools in order to achieve the best trading results for both swing trade that uses daily bars and intraday trade that uses minutes bars? We designed Machine Learning (ML) systems that can trade four major cryptocurrencies: Bitcoin, Ethereum, BNB, and Solana. We found that more indicators do not necessarily mean better trading performance. Swing traders that use daily bars should trade Bitcoin and Solana using Ichimoku Cloud (IC) plus Moving Average Convergence Divergence (MACD), Ethereum with IC plus Chaikin Money Flow (CMF), and BNB with IC alone. With regard to intraday trading, we documented that different cryptocurrencies should be trading using different time frames. These results emphasize that the optimal number of indicators that are used to trade daily bars is one or, at maximum, two. The Multi-Layer (MUL) system that consists of all three examined technical indicators failed to improve the trading results for both days (swing) and intraday trades. The main implication of this study for traders is that more indicators does not necessarily improve trades performances.
Hyperledger Fabric is another development of blockchain technology after Ethereum, which is more suitable as an operating platform for smart contracts. However, the testing technology of Hyperledger Fabric smart contracts (also known as chaincode) is not yet mature currently. Based on this, this paper studies the vulnerability detection of Golang chaincodes. Firstly, we summarize 17 kinds of Golang chaincode vulnerabilities by investigating existing research. Secondly, taking the high accuracy of dynamic detection and the high efficiency of static detection into consideration, we propose a chaincode vulnerability detection framework that combines the dynamic symbolic execution and the static abstract syntax tree analysis technology. We also implement a supporting-tool that can detect the above 15 types of vulnerabilities. Finally, we test the tool by 15 chaincodes collected from GitHub and unknown vulnerabilities were detected in 13 projects. The precision turned out to be 91% after manual inspection. In order to verify the recall rate, we manually inject 30 vulnerabilities into the collected chaincodes and all of them are detected. The evaluation results show the accuracy of the proposed vulnerability detection method for Hyperledger Fabric smart contracts.
Open access
Blockchain Technology Applications and Security
Advanced Steganography and Watermarking Techniques
Michell Boerger, Philipp Lämmel, Nikolay Tcholtchev, Manfred Hauswirth
Climate change has put significant pressure on energy markets. Political decisions such as the plan of the German government to shut down coal power plants by 2038 are shifting electricity production towards renewable and distributed energy resources. The share of these resources will continue to grow significantly in the coming years. This trend changes the ways how energy markets work which mandates fundamental changes in the underlying IT infrastructure. In this paper, we propose a blockchain-based solution which enables an economically viable and grid-serving integration of distributed energy resources into the existing energy system. Our blockchain-based approach targets intraday and day-ahead operating reserve markets, on which energy grid operators and operators of distributed energy resources can trade flexibilities within the schedulable energy production and consumption of their resources. By utilizing these flexibilities as an operating reserve, renewable and climate-friendly technologies can contribute to maintaining the grid stability and security of supply while simultaneously creating economically interesting business models for their operators. We propose to define blockchain-based short-term energy markets by utilizing the concept of general-purpose smart contracts and cryptocurrencies. This enables direct and decentralized trading of energy flexibilities without any intermediary or central instance. We demonstrate the feasibility of our approach through an implementation of a prototype of the proposed markets based on the Ethereum blockchain and provide a detailed evaluation of its efficiency and scalability.
Abstract 
 Often the rapid development of the world economy and also Islam is the majority of Indonesian people, as Muslims must understand technology Cryptocurrencies and activities related to these technologies, as well as understanding the law in Islamic Sharia are sourced from Hadith and verses of the Koran. Cryptocurrency is virtual money, digital money, or electronic money that exists in cyberspace and does not have a concrete form of object. This cryptocurrency has many kinds, including Litecoin, Monero, Ether, Ripple, Ethereum, Qtum, Dash, Zcash, and Bitcoin. Bitcoin security is protected by Blockchain technology. However, Bitcoin does not have an underlying asset (underlaying asset) and there is no responsible authority agency, its ownership is anonymous, its value fluctuations are very extreme, and is dominated by the opinion publication factor of the marketing system. That is why the use of Bitcoin in investment and business transactions raises pros and cons among economists and scholars. This study aims to get an overview of Bitcoin technology, especially about Blockchain and the legitimacy of its use in investment and business transactions according to Islamic law. The applied theory used is the business taxonomy of haram lidzatihi and haram lighairihi from the number of scholars reconstructed by Adiwarman Abdul Karim. This research is a literature study. The data sources for this research were taken from the Koran, the hadith of the Prophet, classical and contemporary books, as well as from online media sources. From this study, it was found that Bitcoin technology with Blockchain can indeed be recognized as an excellent revolutionary technology, but its use as an investment instrument contains elements of maysir (betting) and as an instrument of business transactions contains elements of gharar. Its legal position is haram lighairihi.
 Keywords: Cryptocurrency, Bitcoin, Blockchain technology, Islamic Sharia
 
 Abstrak
 Seriring pesatnya perkembangan ekonomi dunia dan juga agama Islam merupakan mayoritas masyarakat Indonesia, selaku umat Islam harus memahami teknologi Cryptocurrency dan kegiatan-kegiatan yang berhubungan dengan teknologi tersebut, serta memahami hukumnya dalam Syariat Islam bersumber dari Hadist dan ayat - ayat Al-Quran. Cryptocurrency adalah uang virtual, uang digital, atau uang elektronik yang berada di dunia maya dan tidak memiliki bentuk benda yang konkret. Cryptocurrency ini memiliki banyak macam, antara lain Litecoin, Monero, Ether, Ripple, Ethereun, Qtum, Dash, Zcash, dan Bitcoin. Keamanan Bitcoin dilindungi oleh teknologi Blockchain. Namun, Bitcoin tidak memiliki asset yang mendasari (underlaying asset) dan tidak ada lembaga otoritas yang bertanggung jawab, kepemilikannya anonim, fluktuasi nilai yang sangat ekstrem, dan lebih didominasi oleh faktor publikasi opini sistem pemasaran. Itulah sebabnya penggunaan Bitcoin dalam investasi dan transaksi bisnis menimbulkan pro dan kontra di kalangan pakar ekonomi dan ulama. Penelitian ini bertujuan untuk mendapat gambaran seputar teknologi Bitcoin, terutama tentang Blockchain serta keabsahan penggunaannya dalam investasi dan transaksi bisnis menurut syariat Islam. Teori terapan yang digunakan adalah taksonomi bisnis haram lidzatihi dan haram lighairihi dari jumhur ulama yang direkonstruksi oleh Adiwarman Abdul Karim. Penelitian ini bersifat studi pustaka. Sumber data penelitian ini diambil dari Alquran, hadis Rasullah, kitab-kitab klasik dan kontemporer, serta dari sumber media online. Dari penelitian ini didapatkan hasil bahwa teknologi Bitcoin dengan Blockchain memang bisa diakui sebagai teknologi revolusioner yang sangat baik, tetapi penggunaannya sebagai instrumen investasi mengandung unsur maysir (pertaruhan) dan sebagai instrumen transaksi bisnis mengandung unsur gharar. Kedudukan hukumnya adalah haram lighairihi.
 Kata kunci: Cryptocurrency, Bitcoin, teknologi Blockchain, syariat Islam
This study investigates the asymmetric shock transmission mechanisms between seven large cryptocurrencies and crude oil at different market conditions across time. Wavelet technique was used to decompose the daily return series of the assets into wavelet scales to capture trading horizons. We applied quantile regression (QR) and quantile-in-quantile Regression (QQR) on the decomposed series to capture the bear (bull) market conditions. Applying the QR, we found Ethereum, Steller, Ripple and Monero as hedges for oil market volatility at all market regimes from medium to long terms. The QR undermined the hedging properties of Bitcoin, Litecoin and Das, suggesting possible spread of market disruptions from these markets to crude oil market. We observe from QQR that the assets have negative influence on each other at bear market but positive influence at bull market across time, signifying hedging possibilities for both assets in bear market. The significance of our finding is strengthened by the recent rise in the market share of cryptocurrencies.
Ben Weintraub, Christof Ferreira Torres, Cristina Nita-Rotaru, Radu State
The rise of Ethereum has lead to a flourishing decentralized marketplace that has, unfortunately, fallen victim to frontrunning and Maximal Extractable Value (MEV) activities, where savvy participants game transaction orderings within a block for profit. One popular solution to address such behavior is Flashbots, a private pool with infrastructure and design goals aimed at eliminating the negative externalities associated with MEV. While Flashbots has established laudable goals to address MEV behavior, no evidence has been provided to show that these goals are achieved in practice. In this paper, we measure the popularity of Flashbots and evaluate if it is meeting its chartered goals. We find that (1) Flashbots miners account for over 99.9% of the hashing power in the Ethereum network, (2) powerful miners are making more than $2\times$ what they were making prior to using Flashbots, while non-miners' slice of the pie has shrunk commensurately, (3) mining is just as centralized as it was prior to Flashbots with more than 90% of Flashbots blocks coming from just two miners, and (4) while more than 80% of MEV extraction in Ethereum is happening through Flashbots, 13.2% is coming from other private pools.
Global economic markets are encountering apprehensions and susceptibilities after the pandemic of COVID-19. Investment patterns are becoming restrained because of uncertain global scenarios and reduced GDP worldwide. World economies are moving towards digital era and investors are becoming more open towards the newest forms of investments. Due to the uncertain scenarios, investors globally are looking forward to some lucrative forms of investments and cryptocurrencies are the ray of hope for global investors. The present study is attempt to explore the changing dynamics of cryptocurrencies with the market uncertainties. Volatility of five cryptocurrencies, namely Bitcoin, Ethereum, XRP, Chainlink and Bitcoin Cash are analysed using the Generalised AutoRegressive Conditional Heteroskedasticity Model. Results showed that the investors preferred taking cautious decisions and invested more in famous bitcoin rather than other cryptocurrencies.
With the rapid development of e-commerce systems, the centralized service model gradually fails to meet the needs of SMEs. In the existing centralized e-commerce system, users’ transaction data and reputation scores are stored in a centralized cloud server, which has high storage cost, low processing efficiency, and the data is vulnerable to attacks and leaks. However, the existing decentralized e-commerce systems more than its reputation system to store the average credit score evaluation are receiving unfair evaluations against risk. The system of malicious nodes and no disciplinary measures, is not conducive to system development. To solve this problem, this paper proposes a blockchain-based decentralized e-commerce transaction system. The system commodity information is stored in the Interplanetary File System (IPFS) and the returned commodity addresses are stored in the blockchain to enhance the service performance. This paper proposes a reputation evaluation model based on multi-criteria decision making (MCDM), which can effectively resist unfair evaluation and collusion attacks, and proposes an incentive mechanism based on reputation value to reward and punish nodes, thus promoting the good circulation of the system. We implement the proposed system based on Ethereum. The experimental results show that the system has a small communication cost, accurately reflects the user’s reputation value, and has good availability and reliability.
T. Shanthi, M. Ramprasath, A. Kavitha, T. Muruganantham
The latest 6G improvements secured autonomous driving's realism in Intelligent Autonomous Transport Systems (IATS). Despite the IATS's benefits, security remains a significant challenge. Blockchain technology has grown in popularity as a means of implementing safe, dependable, and decentralised independent IATS systems, allowing for more utilisation of legacy IATS infrastructures and resources, which is especially advantageous for crowdsourcing technologies. Blockchain technology can be used to address security concerns in the IATS and to aid in logistics development. In light of the inadequacy of reliance and inattention to rights created by centralised and conventional logistics systems, this paper discusses the creation of a blockchain-based IATS powered by deep learning for secure cargo and vehicle matching (BDL-IATS). The BDL-IATS approach utilises Ethereum as the primary blockchain for storing private data such as order and shipment details. Additionally, the deep belief network (DBN) model is used to select suitable vehicles and goods for transportation. Additionally, the chaotic krill herd technique is used to tune the DBN model’s hyperparameters. The performance of the BDL-IATS technique is validated, and the findings are inspected under a variety of conditions. The simulation findings indicated that the BDL-IATS strategy outperformed recent state-of-the-art approaches.
Simon Laursen Bager, Boris Düdder, Fritz Henglein, Juan Manuel Hébert · 5 authors
Blockchain and distributed ledger technology (BC/DLT) provides distributed databases with decentralized governance, tamper-proof recording, high availability and non-copyable digital assets, which have made it a natural technological basis for supply chain management. In this paper, we introduce REALISTIC, a novel event-based modeling framework for supply chain networks (SCNs) that includes production processes . It extends McCarty’s Resources-Events-Agents (REA) accounting model with secure transformations , which, across the entire SCN, guarantee that certified output resources cannot be digitally produced ex nihilo , but require certified input resources of at least the same amount as what is produced. This generalizes the no-double-spend guarantee of current BC/DLT to (digital twins of) physical resources and their production. Authenticated human or robotic Internet of Things (IoT) actors digitally sign and cryptographically commit to the veracity of real-world events on an immutable database, without having to take responsibility for their aggregate consequences. User-specifiable interpretations, corresponding to queries and analytical functions in database systems, provide auditable aggregate information computed from recorded events across the entire SCN. This includes fine-grained and trustworthy tracing of final products through multiple stages of production processes, semi-finished products, quality certifications and transportation all the way back to their raw materials. We present a case study for an end-to-end coffee supply chain that tracks fine-grained and detailed information from a farmer’s coffee cherries to retail coffee bags, involving all its actors. Our model handles product provenance; auditable sustainability, quality and trade information; production processes from parchment via green to roasted coffee; product quality tests; farmer certifications; and transportation across the entire coffee supply chain. It is based on field work involving farmers, cooperatives, processors, traders, importers, and a major roasting company stretching from Colombia to Scandinavia. Its REALISTIC-based modeling is the foundation for the design of our prototype implementation, which includes Ethereum blockchain code, RDBMS-based server code and a web app client. Their source code is publicly available on GitHub.
Digital collection and maintenance of evidence corresponding to an accident is of utmost relevance as vehicles become connected and part of Internet of things ecosystem. A conceptual evidence management framework is proposed examining the future of accident investigation forensics in the era of connected vehicles. The framework discusses how evidence generated from vehicles involved in incident along with supporting evidence from nearby vehicles CCTVs and road users can be collected and managed over blockchain using smart contracts in a vehicle to everything connected environment. The management of evidence over blockchain serves as an immutable and auditable means to investigate and settle cases post an accident among the stakeholders. Dynamic access control over evidence data and reports based on location of incident and vehicle involved is implemented with the help of smart contracts. The cost of deploying and carrying out transactions using the smart contracts is evaluated over both public and private Ethereum blockchain. Mechanism and cost involved in storing evidence on chain versus off chain using Inter Planetary File System in most optimised manner saving memory and execution cost is compared and presented. The smart contract codes are deployed on Rinkeby test network and can be accessed using address mentioned.
Financial industries operate within a framework of strict regulatory requirements, making compliance a top priority. Smart contracts, integral to the operations of FinTech companies, must align with these regulations. Cloud-based platform offers security as a service (SecaaS) to the scalable and cost-effective solution for analyzing, monitoring, and predicting vulnerabilities in smart contracts. This approach allows FinTech firms to concentrate on their core services while benefiting from specialized security tools. The potential consequences of smart contract vulnerabilities, such as financial losses, fraud, or data manipulation, underscore the critical need for proactive prediction and mitigation. By addressing vulnerabilities in advance, FinTech platforms can prevent financial losses and uphold the integrity of their transactions. Given that FinTech platforms handle customer funds, sensitive financial information, and automated transactions, maintaining trust and reliability is paramount. Predicting vulnerabilities plays a pivotal role in building and sustaining trust among users and stakeholders. This study introduces a hybrid artificial intelligence and optimization technique for smart contract vulnerability prediction in FinTech. The modified barnacles mating optimization (MBMO) algorithm is employed for the extraction of complex syntactic and semantic features, enhancing the accuracy of vulnerability predictions. Additionally, the general regressive artificial neural network (GR-ANN) is utilized to predict vulnerabilities, specifically describing vulnerability types in smart contracts deployed in a cloud environment. The evaluation of this framework involves rigorous testing using the ScrawID-real Ethereum smart contract benchmark dataset, demonstrating its capability and accuracy in predicting smart contract vulnerabilities. The study introduces a novel hybrid artificial intelligence and optimization technique aimed at predicting vulnerabilities in cloud-based smart contracts, specifically in the FinTech sector. Utilizing the modified barnacles mating optimization algorithm and the general regressive artificial neural network, this approach enhances the accuracy of vulnerability detection. The paper demonstrates the methods efficacy through rigorous testing with the ScrawID-real Ethereum smart contract benchmark dataset, highlighting its potential to bolster security in FinTech applications.
This study examined the relationship between cryptocurrency shocks and exchange rate behaviour in Nigeria. Selected cryptocurrencies for the study are Bitcoin, Ethereum, Litecoin, Ripple and Binance coin which are the most traded cryptocurrencies in Nigeria. Augmented Dickey-Fuller (ADF), Johansen Cointegration and Vector Autoregressive (VAR) tests were used to analyze the monthly data of exchange rate and selected cryptocurrencies for four years (45 months). The result of the cointegration test revealed the existence of a long-run relationship among the variables. ECM result showed that about 6% of the short-run disequilibrium are being corrected and integrated into the long-run equilibrium relationship. In addition, the Variance Decomposition result showed that Ripple has the highest variations to exchange rate in the short and long runs. The present value of exchange rate adjusts slightly to changes in cryptocurrency. Ripple and Bitcoin have the highest shocks on the exchange rate. Therefore, monetary authorities should give adequate attention to cryptocurrency transactions and make policy decisions on how to reduce the prevailing high exchange rate in Nigeria by integrating crypto transactions in their systems. Transaction in cryptocurrency is still at the early stage, especially in Nigeria; only five years data can be gotten on commonly traded cryptocurrencies in Nigeria. This is a limitation to the study in terms of the number of cryptocurrencies used in the study. More cryptocurrencies can be included in future studies.
Tushar S Menon, Aviral Srivastava, x Aditya, K R Radhika
Ridesharing is an effective method to resolve traffic congestion and also reduce pollution due to excess vehicles on-road. However, the centralized nature of the current ridesharing systems is not ideal for the user. The lack of transparency in the system as well as risk of data security is a big demerit for such a system. To keep the third-party involvement minimal, a trustless, decentralized peer-to-peer ridesharing DApp is being proposed using a private Ethereum blockchain. Credibility of ride sharing systems can be improved by implementing blockchain technology. Blockchains are decentralized databases where every single piece of information is stored on systems everywhere which can be retrieved and traced freely by anyone on the network. The system will no longer be trust-based but simply based on concrete proof that exists which is built into the ledger. In a blockchain-based system, a rider will anonymously post a ride request. A driver can accept the request and provide their id details and quote. The rider can choose if the transaction is fair and accept the quote and begin his ride. Various other concepts such as time-locked deposit and proof-of-elapsed distance have been introduced to ensure further security for driver and rider. The primary goal of such a system is to develop a reliable and transparent ride sharing system where users do not have to worry about their privacy.
Non-Fungible Tokens (NFT's) is a form of digital certificate of authentication being created on the blockchain technology which is similar to other virtual crypto assets and currencies. The popularity of the blockchain technology along with dealing in crypto assets has seen to grow in the recent years. The NFT market is also rising exponentially as witnessed in the recent years. The very concept of NFT originates from a token standard of Ethereum, aiming to differentiate and distinguish each token with its unique signature being bound with digital properties. The impressive return on its rapidly increasing market worldwide has drawn massive attention, with India too having witnessed a heightened interest in this digital sector, especially from the upcoming new-age investors and digital creators. However, development of the NFT ecosystem being in an early stage has seen an absence of a regulatory legal framework to govern such pre-mature digital crypto assets in the country of India. The legal policies surrounding them are plentiful which has further lead to a lack of clarity in regards to its legal validity and sanctity. The upcoming artists may tend to get lost in this frenetic evolution with lack of systematic summaries. This paper intends to explore the concept of NFT in contrast to cryptocurrency and copyright along with its working and technical components. It aims to analyse the legal pitfalls which impact its functioning along with the opportunities and challenges faced by the Indian legal framework in terms of cryptographic assets.
Tato práce se zabývá implementací modulů do vznikajícího nástroje Woke určeného pro analýzu smart kontraktů na platformě Ethereum. V práci je detailně popsán Ethereum blockchain a programovací jazyk Solidity určený pro vývoj aplikací na tuto platformu. Dále je v práci analyzován nástroj Slither, který je, stejně jako nástroj Woke, napsaný v jazyce Python. Praktická část práce popisuje postup implementace jednotlivých modulů nástroje Woke a jejich testování.
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Ming Fong Sie, Jingze Wu, Seth Austin Harding, Chien-Lung Lin · 6 authors
Technologies designed for digital provenance, especially the Internet of Things (IoT) and blockchain, may allow for security, transparency, and traceability in the global supply chain. However, upstream nodes in the supply chain that work for large-scale production suppliers are not considered. In addition, most IoT blockchain systems adopt an ID-based signature scheme that may affect the efficiency of IoT devices. We propose using aggregate verification to improve the security and efficiency of ID-based verification, reduce network traffic on the blockchain, and transfer computing overhead to aggregator nodes. This paper implements a multi-layer blockchain for Agriculture 4.0 supply chain management that has higher efficiency, effectiveness, and security in comparison to conventional blockchains. We design a Multi-Layer Aggregate Verification (MLAV) solution to improve supply chain management with IoT Blockchain for Agriculture 4.0 through the following methods. First, we use a multi-layer IoT blockchain system to reduce Ethereum gas fee. Second, we design an ID-based Aggregate Verification scheme, thereby eliminating the certificate management cost in the traditional Public Key Infrastructure (PKI) and reducing bandwidth and computation time requirements. Third, we implement a three-layer blockchain infrastructure. In Layer 1, IoT devices sense and upload data to the system's database; in Layer 2, smart contracts execute aggregate ID-based signature verification from IoT devices and upload the transactions to the private blockchain; in Layer 3, a batch converts the layer 2 data and uploads its Merkle root to Ethereum, thereby reducing the required gas fee.
Open access
Blockchain Technology Applications and Security
IoT and Edge/Fog Computing
Advanced Steganography and Watermarking Techniques