Over the years, Cloud Computing has become rapidly embraced due to its flexibility and cost-effectiveness. However, it also presents a number of security challenges, especially with regards to access control. Conventional access control methods, like Role-based Access Control, have limitations in terms of centralized control, lack of transparency, and susceptibility to cyber-attacks. As a result, there is a need for more efficient, transparent, and secure Access Control mechanisms in Cloud Computing environments. In this Research paper, we put forward a non-centralized and tamper-proof Access Control mechanism that uses smart contract blockchain technology to address these limitations. Our model leverages the Ethereum platform's smart contract feature to stockpile access control programs and enable secure verification of user’s access requests. The smart contract blockchain is immutable, transparent, and decentralized, which makes it resistant to tampering and provides a high degree of transparency in the access control process. Our proposed model has several advantages over traditional access control mechanisms. Firstly, it provides an effective and automated approach to manage access control policies. With our model, access control policies can be easily updated and enforced through smart contracts, which eliminates the need for manual updates and reduces the risk of errors. Secondly, it provides a high degree of transparency in the access control process, which allows users to verify the legitimacy of their access requests and ensures that access control policies are being enforced fairly. Finally, it offers a heightened level of security, as the Smart Contract Blockchain is resistant to tampering and it offers a platform for Access Control that is both secure and non-centralized. To assess the efficacy of our model for Access Control management, we performed a series of experiments in a simulated Cloud Computing environment. The findings revealed that our model offers a superior and secure approach for managing access control programs compared to conventional methods. To conclude, our study suggests a secure and non-centralized access control solution by utilizing blockchain technology through smart contracts, to address the limitations of conventional Access Control methods in Cloud Computing environments. Our model provides a more efficient, transparent, and secure way to manage Access Control program to maintain the authenticity and confidentiality of Cloud services.
In a distributed peer-to-peer network, blockchain technology enables the secure transmission of digital assets.This is done based on intellectual agreement capabilities.Indeed, blockchain world has developed into a tool for managing transversal processes on an unbiased platform.Process mining has evolved as a well-known toolkit for comprehending different organization processes.Recently, researchers developed strategies for resolving the issue of collecting reliable data gathered from blockchains in order to improve the examination of blockchain applications employing process mining.There is yet to be a clear assessment of the utility of process mining on public blockchain event logs.In this paper, we will validate the applicability of process mining on public blockchain event logs by treating ChickenHunt data set.ChickenHunt is a competitive game that is operated as a Decentralized application on Ethereum blockchain network.
Blockchain has been recognised as a technological breakthrough with the ability to support new decentralised security-based solutions in sectors such as information technology and finance. Blockchain allows different communities to create Decentralised Autonomous Organisations (DAOs), which are self-organised democratic organisations controlled by smart contracts. This paper presents a new DAO model for the procurement of services by public organisations, such as government agencies. To demonstrate the advantages of this solution, this work looks specifically at current public procurement systems that resort to third-party contractors that manage these negotiations. Third parties lack the transparency, security, and democratic representation that a DAO can provide. We present the implementation of a DAO as a set of smart contracts executed on Ethereum-compatible permissionless blockchains, supported by a consensus algorithm, replacing third-party contractors.
With the increasing popularity of Web 3.0, tokenomics is becoming even more important as a scientific discipline. Tokenomics auditing is a new area of interest in the context of Web 3.0 whose aim is to stress test the design and structure of token economies, to ensure they are robust and safe. The importance of this area has increased considering multiple project failures and fraud that were witnessed in the recent history of the space. In this paper we present a framework to audit the tokenomics of blockchain-based projects. The auditing framework can be used by stakeholders to audit their tokens and by investors to assess the risks associated with investing in a given token. We demonstrate how this framework can be applied to assess risks and improve the structure of a token economy. We give three examples: First, an example is based on a real case study of a newly launched DeFi protocol called Algem which was the original inspiration for this protocol. Then, we perform retrospective study of Terra/Luna. Finally, we show how that framework could be used for the analysis of Ethereum 2.0. While the auditing framework is not without its shortcomings, it represents the first attempt at standardising tokenomics auditing. Therefore, this provides a foundation upon which the community will build and improve, as tokenomics auditing matures as a framework.
Lioba Heimbach, Lucianna Kiffer, Christof Ferreira Torres, Roger Wattenhofer
With Ethereum's transition from Proof-of-Work to Proof-of-Stake in September 2022 came another paradigm shift, the Proposer-Builder Separation (PBS) scheme. PBS was introduced to decouple the roles of selecting and ordering transactions in a block (i.e., the builder), from those validating its contents and proposing the block to the network as the new head of the blockchain (i.e., the proposer). In this landscape, proposers are the validators in the Proof-of-Stake consensus protocol, while now relying on specialized block builders for creating blocks with the highest value for the proposer. Additionally, relays act as mediators between builders and proposers. We study PBS adoption and show that the current landscape exhibits significant centralization amongst the builders and relays. Further, we explore whether PBS effectively achieves its intended objectives of enabling hobbyist validators to maximize block profitability and preventing censorship. Our findings reveal that although PBS grants validators the opportunity to access optimized and competitive blocks, it tends to stimulate censorship rather than reduce it. Additionally, we demonstrate that relays do not consistently uphold their commitments and may prove unreliable. Specifically, proposers do not always receive the complete promised value, and the censorship or filtering capabilities pledged by relays exhibit significant gaps.
George Melas, Alexandros Chatzigeorgiou, Apostolos Ampatzoglou
Smart Contracts (SC) are computer programs that run on blockchains and can be executed automatically in a deterministic way, when pre-determined conditions are met. Currently, Ethereum is the biggest blockchain network with more than 200,000 SCs deployed every month[1](#fn-0002). The main mechanism for financially managing and securing such networks is “ Gas Consumption ”. In particular, a gas cost is assigned to each operation that alters the blockchain state, based on the SC size and complexity. Thus, the cost that a SC incurs to its owner and users is related to the internal structure of the SC. By considering that the average cost for deploying a Smart Contract can reach up to thousands of euros, it becomes obvious that internal quality of SCs is of great importance. To this end, in this article we present a comprehensive analysis of the correlation of a set of code metrics (e.g., size, complexity) with the actual gas required to deploy Smart Contracts. The empirical evidence that we provide rely on the analysis of over 90,000 SCs. In addition to the produced empirical knowledge, in most of the cases validating the theoretical expectation, we have implemented a web-based application (Smart Contracts Quality Analysis Platform—SCQAP) that visualizes the findings, enabling the on-demand creation of correlation diagrams, and offers access to a public repository of our data (metrics and deployment gas consumption) via a REST API. To the best of our knowledge this is the biggest empirical study on SCs, which: (a) sets up the scene for further large-scale studies on Smart Contracts (through tooling and public dataset); and (b) provides guidance to software practitioners on parameters that can inflate deployment costs.
Permissionless blockchains promise to be resilient against censorship by a single entity. This suggests that deterministic rules, and not third-party actors, are responsible for deciding if a transaction is appended to the blockchain or not. In 2022, the U.S. Office of Foreign Assets Control (OFAC) sanctioned a Bitcoin mixer and an Ethereum application, putting the neutrality of permissionless blockchains to the test. In this paper, we formalize quantify and analyze the security impact of blockchain censorship. We start by defining censorship, followed by a quantitative assessment of current censorship practices. We find that 46% of Ethereum blocks were made by censoring actors that intend to comply with OFAC sanctions, indicating the significant impact of OFAC sanctions on the neutrality of public blockchains. We further uncover that censorship not only impacts neutrality, but also security. We show how after Ethereum's move to Proof-of-Stake (PoS) and adoption of Proposer-Builder Separation (PBS) the inclusion of censored transactions was delayed by an average of 85%. Inclusion delays compromise a transaction's security by, e.g., strengthening a sandwich adversary. Finally we prove a fundamental limitation of PoS and Proof-of-Work (PoW) protocols against censorship resilience.
Blockchain technology has gained significant attention as a solution for ensuring data integrity, confidentiality, and availability in a trustless environment.Its main objective is to safeguard data from both internal and external cyberattacks by leveraging the collective power of the network to counter malicious attempts.In this project, we aim to develop a decentralized messaging application using XMTP (replace with the correct protocol if applicable).Our application will enable secure and anonymous transmission of encrypted messages.The Ethereum platform will be utilized for deploying our blockchain network.By utilizing a distributed architecture and a flexible communication protocol, our application will be resilient against various forms of suppression.XMTP's extensible design allows for a wide range of use cases in exchanging message data between web3 identities.Additionally, the XMTP network ensures message persistence and associates them with web3 identities rather than specific client apps.As a result, each web3 identity possesses a portable inbox accessible through any XMTP-enabled client application.
Bassey Isong, Tshipuke Vhahangwele, Adnan M. Abu‐Mahfouz
Client-server-based healthcare systems are unable to manipulate a high data volume, prone to a single failure point, limited scalability, and data integrity. Particularly, several measures introduced to help curb the spread of Covid-19 were not effective and patient records were not adequately managed and maintained. Most vaccination-proof certificates were forged by unauthorized parties and no standard verification medium exists. Therefore, this paper proposes a blockchain-enabled vaccination management system (VMS). VMS utilizes smart contracts to store encrypted patients record, generate vaccination certificates, and verify the legitimacy of the certificate using a QR code. VMS prototype is implemented using Ethereum, a public blockchain and simulations performed based on Apache JMeter and Hyperledger Caliper to assess its performance in terms of throughput, latency and response time, and the average time per transaction. Results show VMS achieved an average: response time of 132.24 ms, the throughput of 379.89 tps, latency of 204.60 ms, and time of transactions is 10s-12s for 1000 transactions. Also, its comparison with the centralized database shows the traditional database’s effectiveness in transaction processing but lacks data privacy and security strengths. We, therefore, recommend the use of blockchain in the healthcare system and other related sectors such as elections, and student records management to ensure data privacy and security and rid the system of a single point of failure.
Ole Delzer, Ingo Weber, Richard Hobeck, Stefan Schulte
Blockchain technology has become one of the most popular trends in IT over the last few years. Its increasing popularity and the discovery of ever more use cases raises the question of how to improve scalability. While researchers are exploring ways to scale the on-chain processing of transactions, the scalability of the off-chain creation of transactions has not been investigated yet. This is relevant for organizations wishing to send a high volume of transactions in a short time frame, or continuously, e.g., manufacturers of high-volume products. Especially for blockchain implementations such as Ethereum, which require transactions to include so-called nonces (essentially a sequence number), horizontally scaling transaction creation is non-trivial. In this paper, we propose four different approaches for horizontal scaling of transaction creation in Ethereum. Our experimental evaluation examines the performance of the different approaches in terms of scalability and latency and finds two of the four proposed approaches feasible to scale transaction creation horizontally.
The metaverse gradually evolves into a virtual world containing a series of interconnected sub-metaverses. Diverse digital resources, including identities, contents, services, and supporting data, are key components of the sub-metaverse. Therefore, a Domain Name System (DNS)-like system is necessary for efficient management and resolution. However, the legacy DNS was designed with security vulnerabilities and trust risks due to centralized issues. Blockchain is used to mitigate these concerns due to its decentralized features. Additionally, it supports identity management as a default feature, making it a natural fit for the metaverse. While there are several DNS alternatives based on the blockchain, they either manage only a single type of identifiers or isolate identities from other sorts of identifiers, making it difficult for sub-metaverses to coexist and connect with each other. This article proposes a M ulti- I dentifier management and resolution S ystem (MIS) in the metaverse, supporting the registration, resolution, and inter-translation functions. The basic MIS is portrayed as a four-tier architecture on a consortium blockchain due to its manageability, enhanced security, and efficiency properties. On-chain data is lightweight and compressed to save on storage while accelerating reading and writing operations. The resource data is encrypted based on the attributes of the sub-metaverse in the storage tier for privacy protection and access control. For users with decentralization priorities, a modification named EMIS is built on top of Ethereum. Finally, MIS is implemented on two testbeds and is available online as the open-source system. The first testbed consists of 4 physical servers located in the UK and Malaysia while the second is made up of 200 virtual machines (VMs) spread over 26 countries across all 5 continents on Google Cloud. Experiments indicate that MIS provides efficient reading and writing performance than the legacy DNS and other public blockchain-based workarounds including EMIS and Ethereum Name Service (ENS).
Nader Naifar, Sohale Altamimi, Fatimah Alshahrani, Mohammed Alhashim
This paper aims to investigate the impact of global financial, economic, and gold price uncertainty indices (VIX, EPU, and GVZ) and investor sentiment based on media coverage news on the returns of Bitcoin and Ethereum during the COVID-19 pandemic. We adopt an asymmetric framework based on the Quantile-on-Quantile approach, which examines the quantiles of the cryptocurrency returns, investor sentiment, and the various uncertainties indicators. The empirical findings suggest that the COVID-19 pandemic has significantly impacted cryptocurrency returns. Specifically, (i) the results demonstrate the predictive power of Economic Policy Uncertainty (EPU) during this period, as evidenced by a strong negative association between EPU and cryptocurrency returns across all quantiles; ( ii ) the correlation between cryptocurrency returns and the VIX index was negative but weak, across various quantile combinations of Ethereum and Bitcoin returns; ( iii ) an increase in COVID-19 news negatively affected Bitcoin returns across all quantiles; ( iv ) Bitcoin and Ethereum cannot be relied upon as effective hedging tools against global financial and economic uncertainty during the COVID-19 pandemic. Studying the behavior of cryptocurrency during uncertainty like pandemics is extremely important because it provides investors with insights on diversifying their portfolios and hedging their risks.
In the world of modern technology, ensuring security is a top priority. To address this issue, blockchain technology has emerged as a promising solution by eliminating intermediaries and enhancing security. Cryptocurrencies are the first type of digital assets that have been successfully managed using blockchain technology. In recent years, financial institutions have been increasingly adding cryptocurrencies to their portfolios, leading to widespread adoption and interest among various stakeholders, including the banking sector, government, and individual investors. Cryptocurrency has the potential to become the future global currency, replacing fiat currency. This research project provides a comprehensive overview of the cryptocurrency market, including its origins, key features, price dynamics, market capitalization, and trading volumes. The project also explores important concepts such as Ethereum, smart contracts, tokens, and consensus algorithms that are critical to the functioning of the cryptocurrency market.
Cryptocurrencies have gained popularity and are increasingly used in the global financial system, despite their volatile nature. They have become an attractive financial instrument for individuals and corporations due to their potentials for high returns, decentralized nature, and exemption from strict government regulations. This study aims to investigate how cryptocurrency volatility affects the performance of companies listed on the Nigerian Exchange Limited (NGX). The study uses an ex post facto research design and the GARCH (1,1) model. Weekly data on Bitcoin and Ethereum were obtained from www.ng.investing.com and used to construct a cryptocurrency composite index with principal component analysis (PCA). The All-Share Index data were extracted from the Security and Exchange Commission (SEC) statistical bulletin between January 2017 and December 2021. The result of the mean equation shows that cryptocurrency trading in Nigeria responds more to positive sentiment and good news than bad news, while the variance equation reveals that current conditional volatility of cryptocurrencies and companies' performance is influenced by their previous shocks and past volatility conditions. The study also found evidence of volatility clustering in companies’ performance on the NGX. Therefore, investors are advised to exercise caution in an expanding cryptocurrency market, while regulators and policymakers should use relevant indicators to avoid contagion risk that could spread to the stock market. This paper is significant and relevant to achieving the Nigerian government's plan to introduce an official virtual currency.
With the emergence of Miner Extractable Value (MEV), block construction markets on blockchains have evolved into a competitive arena. Following Ethereum's transition from Proof of Work (PoW) to Proof of Stake (PoS), the Proposer Builder Separation (PBS) mechanism has emerged as the dominant force in the Ethereum block construction market. This paper presents an in-depth longitudinal study of the Ethereum block construction market, spanning from the introduction of PoS and PBS in September 2022 to May 2023. We analyze the market shares of builders and relays, their temporal changes, and the financial dynamics within the PBS system, including payments among builders and block proposers -- commonly referred to as bribes. We introduce an MEV-time law quantifying the expected MEV revenue wrt. the time elapsed since the last proposed block. We provide empirical evidence that moments of crisis (e.g. the FTX collapse, USDC stablecoin de-peg) coincide with significant spikes in MEV payments compared to the baseline. Despite the intention of the PBS architecture to enhance decentralization by separating actor roles, it remains unclear whether its design is optimal. Implicit trust assumptions and conflicts of interest may benefit particular parties and foster the need for vertical integration. MEV-Boost was explicitly designed to foster decentralization, causing the side effect of enabling risk-free sandwich extraction from unsuspecting users, potentially raising concerns for regulators.
Virtual Economies continue to be a global phenomenon, and cryptocurrency is prominent in this process, and it can be attained by playing blockchains. The rise of non-fungible tokens (NFTs) is also increasing the demand for Ethereum. Thus, these features encourage many people to earn money while playing it that even young people (most likely undergraduate students) invest. There is no doubt that it is a good business for financial risk and problems, it also provides much more significant opportunities and applications. Somehow the notions of blockchain technology provides some negative outcomes, specifically in the behavioral aspects of them. In this paper, the researchers focused on socioeconomic status and behavioral aspects of the players and considered these two as the factors in their perspective about the blockchain games. The results on socioeconomic shows that most of them are playing because of financial problems and sees this as an opportunity to have an income. The results on Behavioral impacts through pareto analysis shows that most respondents suffer from the negative impact of playing blockchain games, 66% of the respondents has lack of sleep, 53.5% less focus in studies, 39.5% less interactive and more. Tukey method is also use to analysis whether which questions is significantly important in terms of obtaining and analysis the results from the survey conducted. In conclusion the socioeconomic stand is likely to affect their perspective in the blockchain games and shows that these games can lead to addiction because of the time spend in playing, the anxiety with the game and other negative outcomes.
Zhen Zhang, Tao He, Kai Chen, Boshen Zhang · 6 authors
As the use of digital currencies, such as cryptocurrencies, increases in popularity, phishing scams and other cybercriminal activities on blockchain platforms (e.g., Ethereum) have also risen. Current methods of detecting phishing in Ethereum focus mainly on the transaction features and local network structure. However, these methods fail to account for the complexity of interactions between edges and the handling of large graphs. Additionally, these methods face significant issues due to the limited number of positive labels available. Given this, we propose a scheme that we refer to as the Bagging Multiedge Graph Convolutional Network to detect phishing scams on Ethereum. First, we extract the features from transactions and transform the complex Ethereum transaction network into three simple inter-node graphs. Then, we use graph convolution to generate node embeddings that leverage the global structural information of the inter-node graphs. Further, we apply the bagging strategy to overcome the issues of data imbalance and the Positive Unlabeled (PU) problem in transaction data. Finally, to evaluate our approach’s effectiveness, we conduct experiments using actual transaction data. The results demonstrate that our Bagging Multiedge Graph Convolutional Network (0.877 AUC) outperforms all of the baseline classification methods in detecting phishing scams on Ethereum.
With the overall momentum of the blockchain industry, crypto-based crimes are becoming more and more prevalent. After committing a crime, the main goal of cybercriminals is to obfuscate the source of the illicit funds in order to convert them into cash and get away with it. Many studies have analyzed money laundering in the field of the traditional financial sector and blockchain-based Bitcoin. But so far, little is known about the characteristics of crypto money laundering in the blockchain-based Web3 ecosystem. To fill this gap, and considering that Ethereum is the largest platform on Web3, in this paper, we systematically study the behavioral characteristics and economic impact of money laundering accounts through the lenses of Ethereum heists. Based on a very small number of tagged accounts of exchange hackers, DeFi exploiters, and scammers, we mine untagged money laundering groups through heuristic transaction tracking methods, to carve out a full picture of security incidents. By analyzing account characteristics and transaction networks, we obtain many interesting findings about crypto money laundering in Web3, observing the escalating money laundering methods such as creating counterfeit tokens and masquerading as speculators. Finally, based on these findings we provide inspiration for anti-money laundering to promote the healthy development of the Web3 ecosystem.
With the increasing demand of virtual currency, cryptocurrencies are gaining popularity throughout the world for transactions be it legal or illegal. The yields returned from investment in crypto currency these days are huge but their existence and reliability has always been questioned. A cryptocurrency uses cryptography for implementing security. In spite of several problems in crypto currencies, the growing success of Bitcoin since its launch has emerged in a number of organizations coming forward with substitute cryptocurrencies .This study tries to present a comparison of six famous cryptocurrencies - Bitcoin, Ethereum, Litecoin, Dash, Monero and IOTA in the light of their volatility and strengths in present times and also discusses their current trends. A thorough study of literature showed that no paper has been presented keeping in mind only these six currencies, so this article is the first of its kind to present a comparison of technicalities of these cryptocurrencies.
This study explores whether Islamic equities offer portfolio diversification benefits to cryptocurrency investors. It employs the Continuous Wavelet Transform model to examine the nature of coherence between major cryptocurrency asset classes and major Asian Islamic equity markets on different investment horizons. We consider a range of Islamic equity indices for multiple countries and a basket of three prominent cryptocurrencies: Bitcoin, Ethereum and Ripple. Findings suggest that Asian Islamic equities offer portfolio diversification opportunities. Our findings also imply that Asian Islamic equities are not efficient and are prone to short-term speculative activities.
Smart contract vulnerabilities have led to significant financial losses, with their increasing complexity rendering outright prevention of hacks increasingly challenging. This trend highlights the crucial need for advanced forensic analysis and real-time intrusion detection, where dynamic analysis plays a key role in dissecting smart contract executions. Therefore, there is a pressing need for a unified and generic representation of smart contract executions, complemented by an efficient methodology that enables the modeling and identification of a broad spectrum of emerging attacks We introduce C lue , a dynamic analysis framework specifically designed for the Ethereum virtual machine. Central to C lue is its ability to capture critical runtime information during contract executions, employing a novel graph-based representation, the Execution Property Graph. A key feature of C lue is its innovative graph traversal technique, which is adept at detecting complex attacks, including (read-only) reentrancy and price manipulation. Evaluation results reveal C lue ’s superior performance with high true positive rates and low false positive rates, outperforming state-of-the-art tools. Furthermore, C lue ’s efficiency positions it as a valuable tool for both forensic analysis and real-time intrusion detection.
Ronan D. Mendonça, Ericksulino Moura, Glauber Dias Gonçalves, Alex Borges Vieira · 5 authors
Blockchain é uma tecnologia que amplia a segurança nas relações entre organizações via o registro auditável e descentralizado de transações. Notadamente, há uma crescente atenção por aplicações que utilizam essa tecnologia. Entretanto, a eficiência e custo de tais aplicações pode ser influenciada pela rede blockchain utilizada. De fato, a escolha da rede impacta nas qualidades não funcionais das aplicações, em especial desempenho (e.g., em relação a taxa de transações efetivadas) e custo. Este artigo investiga o impacto no desempenho e custo da infraestrutura de rede blockchain para lidar com uma determinada carga de trabalho. Primeiramente, este artigo propõe um modelo de arquitetura de rede comum entre a rede pública Ethereum e permissionada Hyperledger Fabric com base em recursos por nó par da rede blockchain. A seguir, avalia-se o custo por transação para aplicações nessa arquitetura considerando latências e custos mínimos para os pares da rede, em função da carga de trabalho. Os experimentos realizados nas plataformas mais populares para redes blockchain, Ethereum e Hyperledger Fabric, mostram os limites de escalabilidade dessas plataformas e os seus compromissos entre custo e desempenho no projeto de aplicações baseadas em blockchain.