Shiyi Lin, Lei Zhang, Jing Li, Li-li Ji · 5 authors
Nowadays, blockchain technology and industry has developed rapidly all over the world, which is inseparable from continuous innovation and improvement on smart contract technology. Therefore, by summarizing the working principle and application research status of blockchain smart contract, this paper analyzes the development and challenges of smart contract. Firstly, we introduce the model and operation principle of blockchain smart contract for the overall architecture, analyze the deployment process of smart contract with Ethereum, Hyperledger Fabric and EOSIO, and make a comparative analysis from the technical level. And taking Byteball, InterValue and IOTA platforms as examples, we introduce the deployment process and application potential for DAG-based blockchain smart contract. Additionally, we also summarize the application research of smart contract for international and Blockchain Oracle, and discuss its innovative application and development trend in the future. Secondly, we introduce the application status of smart contract with Ethereum and Hyperledger Fabric platforms from the aspects of financial transactions, Internet of things, medical applications, and supply chain, and further discuss EOS (enterprise operation system), Blockchain Oracle and other application fields. Furthermore, we introduce the application advantages and challenges to smart contract for industrial Internet from the fields of manufacturing, food industry, industrial Internet of things and industry 4.0. Finally, we discuss the challenges faced by smart contract with technical issues, analyzes the impact on large-scale applications and mining system on the sustainable development of smart contract, and looks forward to the future research direction of blockchain smart contract.
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A transaction fee mechanism (TFM) is an essential component of a blockchain protocol. However, a systematic evaluation of the real-world impact of TFMs is still absent. Using rich data from the Ethereum blockchain, the mempool, and exchanges, we study the effect of EIP-1559, one of the earliest-deployed TFMs that depart from the traditional first-price auction paradigm. We conduct a rigorous and comprehensive empirical study to examine its causal effect on blockchain transaction fee dynamics, transaction waiting times, and consensus security. Our results show that EIP-1559 improves the user experience by mitigating intrablock differences in the gas price paid and reducing users' waiting times. However, EIP-1559 has only a small effect on gas fee levels and consensus security. In addition, we find that when Ether's price is more volatile, the waiting time is significantly higher. We also verify that a larger block size increases the presence of siblings. These findings suggest new directions for improving TFMs.
Ransomware attacks have caused serious data loss, and a frequent/good backup is the only solution to deal with such risks. Unfortunately, current research of data backup mainly focuses on improving data recovery efficiency, and rarely takes backups confidentiality and service DDoS attacks resistance into consideration, which greatly limits their usability in practice. In this work, we propose a novel data backup scheme called RAP (RAnsomware Protection scheme based on blockchain) to make up for the above deficiencies. Based on the principle of data isolation, we first formally discuss the role of gateways in data backup systems and deploy mechanism on gateways to resist DDoS attacks. RAP employs an optimized all-or-nothing transform (AONT) and offers the scheme for setup, backups upload and data recovery through secure channel. We define and analyze the security of RAP for data confidentiality and DDoS attacks resistance. We instantiate RAP by a consortium blockchain based on Ethereum and evaluate its performance. The running time of each phase in RAP is less than 1 millisecond excluding the$r$ead/$w$rite delay of typic data size and our scheme would be compatible with most existing blockchains, which further demonstrate its practicality and scalability.
Xueyan Liu, Yukun Luo, Xiaotao Yang, Li Wang · 5 authors
The integrity auditing of outsourced data is becoming an essential process because an increasing number of people or organizations are opting to store health records in cloud servers to reduce local storage. Most existing public auditing schemes requiring complex certificate management are unsuitable for resource-limited mobile devices and are unable to resist quantum attacks; thus, we propose a lattice-based proxy-oriented public auditing scheme for electronic health records. We construct an identity-based auditing scheme based on the small integer solution to avoid complex certificate management issues. We also introduce the idea of proxy to reduce computing overhead from the user side significantly and enable the application of resource-limited mobile devices. Furthermore, we improve the proposed scheme by integrating the Ethereum blockchain to resist malicious proxies. We prove that the proposed scheme is proxy-protected, unforgeable, and privacy-protected. Results of an efficiency analysis show that our scheme demonstrates high computing efficiency on the user side and comprehensive functions.
Virtual Machine Image (VMI) is the building block of cloud infrastructure. It encapsulates the various applications and data deployed at the Cloud Service Provider (CSP) end. With the leading advances of cloud computing, comes the added concern of its security. Securing the Cloud infrastructure as a whole is based on the security of the underlying Virtual Machine Images (VMI). In this paper an attempt has been made to highlight the various risks faced by the CSP and Cloud Service Consumer (CSC) in the context of VMI related operations. Later, in this article a formal model of the cloud infrastructure has been proposed. Finally, the Ethereum blockchain has been incorporated to secure, track and manage all the vital operations of the VMIs. The immutable and decentralized nature of blockchain not only makes the proposed scheme more reliable but guarantees auditability of the system by maintaining the entire VMI history in the blockchain.
Document verification is the first step whenever we enter any organization or institute. In any organization, it is essential to track, verify, and check the person’s background who will become a part of the organization. This process is very time-consuming and hectic for both parties involved. Various governments provide cloud-based digital locker services for the citizens storing the public document on a centralized server. But due to its centralized nature, this type of service is weak against information breaches and Denial of Service (DoS) attacks. Also, there are some privacy concerns with such centralized digital locker services as the stored documents may contain users’ crucial personal information. This paper proposes a blockchain-based digital locker in a decentralized application using Ethereum Blockchain to securely store personal documents with high availability. The proposed solution also verifies documents with ease, confidentiality, access control, data privacy, authenticity, and maintaining the integrity of documents.
Scarcity of resources is a major problem associated with growing urbanization across the globe. A natural way to address the issue is to share the resources. This solution is not only cost-effective but also sometimes environment friendly. However, sharing resources among people in a trustless environment (in big cities, people do not know each other) and preserving the participant’s privacy are important issues to be addressed. Internet-of-Things and Blockchain together are being considered by the researchers to develop solutions for different smart city applications. In this paper, we propose a privacy preserving blockchain-based framework for multi-vendor IoT-based resource sharing for smart cities. OAuth is integrated with the proposed framework to authorize the blockchain to make the payment from the requester to the service provider. The proposed solution is implemented on the EOS blockchain instead of Ethereum because EOS does not require a fee for executing the smart contract and can conduct millions of transactions per second.
Mukhammaddiyor Khaydaraliev, Min-Hyung Rhie, Ki‐Hyung Kim
Internet of Things (IoT) devices is being conveyed at an enormous scope, with many experts predicting the deployment of 500 billion devices by 2030. Because the IoT devices have limited capabilities and are being deployed in a large amount shortly, current traditional IoT platforms may not be able to handle access control effectively in terms of scalability, reliability, and real-time response. On the other hand, with the advancement of blockchain technology, edge computing, and role-based IoT networks, we can produce a secure access control scheme in a distributed manner with higher reliability, scalability, and real-time response. Therefore, we proposed a decentralized IoT access control system based on blockchain, fog nodes, and the role of things utilizing Ethereum smart contracts for secure device-to-device access. The paper presents overall platform architecture, use case scenarios, crucial evaluation results identified with security analyses, and implementation of the proposed work.
Purpose The main aim of the study is to explore the volatility spillover effect of cryptocurrencies (Bitcoin, Ethereum and Litecoin) on inflation volatility in India. Design/methodology/approach A popular tool, the Bivariate GARCH model (BEKK-GARCH), to study the volatility spillover effect, is applied in the study. Monthly data of cryptocurrencies and inflation (WPI and CPI indices) are gathered from 2015 to 2021. Findings Significant short-term responsiveness of volatility of cryptocurrencies on the inflation volatility is found. In addition to this, the significant volatility spillover effect from the cryptocurrencies to the inflation volatility is found. Practical implications The findings of the current paper can be of use for inflation management, target inflation policies and policies to contain the volatility of cryptocurrencies. The significance of the current paper is relevant as governments worldwide are officially recognizing cryptocurrencies and starting the process of launching their official virtual currency. Originality/value No other study is observed on the topic. Hence, the contribution and novelty of the findings of the current paper are very high and add value to the nonexistent literature on the topic. Lack of the number of inflation observations (data of CPI and WPI are available only in monthly frequency) crimps the model estimation. As the cryptocurrencies become old, more data points will be available by design, and such problems can be resolved, and better model estimation may be possible.
Alberto Partida, Saki Gerassis, Regino Criado, Miguel Romance · 6 authors
In this article, we model the two most market-capitalised public, open and permissionless blockchain implementations, Bitcoin (BTC) and Ethereum (ETH), as a System of Systems (SoS) of public blockchains. We study the concepts of blockchain, BTC, ETH, complex networks, SoS Engineering and intentional risk. We analyse BTC and ETH from an open SoS perspective through the main properties that seminal System of Systems Engineering (SoSE) references propose. This article demonstrates that these public blockchain implementations create networks that grow in complexity and connect with each other. We propose a methodology based on a complexity management lever such as SoSE to better understand public blockchains such as BTC and ETH and manage their evolution. Our ultimate objective is to improve the resilience of public blockchains against intentional risk: a key requirement for their mass adoption. We conclude with specific measures, based on this novel systems engineering approach, to effectively improve the resilience against intentional risk of the open SoS of public blockchains, composed of a non-inflationary money system, “sound money”, such as BTC, and of a world financial computer system, “a financial conduit”, such as ETH. The goal of this paper is to formulate a SoS that transfers digital value and aspires to position itself as a distributed alternative to the fiat currency-based financial system.
Péter Garamvölgyi, Yuxi Liu, Dong Zhou, Fan Long · 5 authors
Traditional public blockchain systems typically had very limited transaction throughput because of the bottleneck of the consensus protocol itself. With recent advances in consensus technology, the performance limit has been greatly lifted, typically to thousands of transactions per second. With this, transaction execution has become a new performance bottleneck. Exploiting parallelism in transaction execution is a clear and direct way to address this and to further increase transaction throughput. Although some recent literature introduced concurrency control mechanisms to execute smart contract transactions in parallel, the reported speedup that they can achieve is far from ideal. The main reason is that the proposed parallel execution mechanisms cannot effectively deal with the conflicts inherent in many blockchain applications. In this work, we thoroughly study the historical transaction execution traces in Ethereum. We observe that application-inherent conflicts are the major factors that limit the exploitable parallelism during execution. We propose to use partitioned counters and special commutative instructions to break up the application conflict chains in order to maximize the potential speedup. When we evaluated the maximum parallel speedup achievable, these techniques doubled this limit to an 18x overall speedup compared to serial execution, thus approaching the optimum. We also propose OCC-DA, an optimistic concurrency control scheduler with deterministic aborts, which makes it possible to use OCC scheduling in public blockchain settings.
Blockchain technology is increasingly being supported for different agricultural commodity applications, including agricultural commodity tracing and provenance establishment. But many critical issues need to be addressed before the use of blockchain technology for this purpose becomes widespread both technologically and ethically. For that, I carried out a comparison of the different blockchain frameworks -mainly permissioned Hyperledger blockchain technology and Ethereum smart in terms of their agricultural sustainability applications. I also examined the role of Internet of Things (IoT) devices in supporting blockchain-driven sustainability. I identified how a lack of earth observation (EO) data undermines commodity provenance (and related ecological sustainability) establishment. However, the biggest threats to widespread blockchain technology adoption, especially for meeting sustainability standards include scalability issues and the lack of standard data protocols and governance measures.
The aim of the study investigates the return and volatility spillovers and conditional correlations between Borsa Istanbul Stock Exchange 100 Index (BIST100) and Bitcoin (BTC), Ethereum (ETH), Ripple (XRP), and Litecoin (LTH) using daily data for the period between August 07, 2015 and May 20, 2021 with VAR-DCC-GARCH model. We find no bidirectional return spillovers between BIST100 and cryptocurrencies. In line with the volatility spillover results of the study, it has been determined that there is a unidirectional shock transmission from BIST100 to BTC, XRP and LTH, and a unidirectional volatility spillover from BIST100 to BTC and ETH. Also, in the study, it has been determined that the dynamic conditional correlations between BIST100 and four cryptocurrencies have a highly variable over time and their average is very close to zero. However, in possible panic periods, the situation is reversed
This paper proposes a NFT (Non-Fungible Token) trading platform over Hyperledger Fabric blockchain, proceeding with performance evaluation to confirm innovatory speed improvement and power conservation. The growing public interest for NFTs in recent years has played a major role in expanding the market size. However, as a result of expansion, massive overload to the Ethereum network occurred, leading to high gas costs for trading NFT assets, which is rather considered a burdensome amount. To overcome this problem, we introduce a NFT trading platform on Hyperledger Fabric with reference to ERC-721 standard of Ethereum. ERC-721 standard is implemented by Hyperledger Fabric chaincode, which is similar to Ethereum smart contract, where all features of the current protocol are implemented. Parallel processing of Hyperledger fabric enables fast NFT trade management with minimal cost since no gas cost is required with Hyperledger Fabric Raft consensus protocol. It is applicable to fields other than the most actively traded works of art. By providing an optimized trading environment, we expect further development of the NFT trading industry.
The StableSims project set out to determine optimal parameters for the new auction mechanism, Liquidations 2.0, used by MakerDAO, a protocol built on Ethereum offering a decentralized, collateralized stablecoin called Dai. We developed an agent-based simulation that emulates both the Maker protocol smart contract logic, and how profit-motivated agents ("keepers") will act in the real world when faced with decisions such as liquidating "vaults" (collateralized debt positions) and bidding on collateral auctions. This research focuses on the incentive structure introduced in Liquidations 2.0, which implements both a constant fee (tip) and a fee proportional to vault size (chip) paid to keepers that liquidate vaults or restart stale collateral auctions. We sought to minimize the amount paid in incentives while maximizing the speed with which undercollateralized vaults were liquidated. Our findings indicate that it is more cost-effective to increase the constant fee, as opposed to the proportional fee, in order to decrease the time it takes for keepers to liquidate vaults.
Several challenges have been announced on arithmetization-oriented hash functions, with bounties funded by the Ethereum Foundation. In this note, we report on our work to solve several of these challenges, on Feistel-MiMC, Rescue Prime and Poseidon. Our results are obtained by writing the challenges as systems of polynomial equations over the large field, and solving them with off-the-shelf tools (SageMath, NTL, Magma).
Purpose The existence of long memory and persistent volatility characteristics of cryptocurrencies justifies the investigation of return and volatility/shock spillovers between traditional financial market asset classes and cryptocurrencies. The purpose of this paper is to investigate the dynamic relationship between the cryptocurrencies, namely Bitcoin and Ethereum, and stock market indices of G7 and E7 countries to analyze the return and volatility spillover patterns among these markets by means of multivariate (MGARCH) approach. Design/methodology/approach Applying the newly developed VAR-GARCH-in mean framework with the BEKK representation, the empirical results reveal that there exists an evidence of mean and volatility spillover effects among Bitcoin and Ethereum as the proxies for the cryptocurrencies, and stock markets reviewed. Findings Interestingly, the direction of the return and volatility spillover effects is unidirectional in most E7 countries, but bidirectional relationship was found in most G7 countries. This can be explained as the presence of a strong return and volatility interaction among G7 stock markets and crypto market. Originality/value Overall, the results of this study are of particular interest for portfolio management since it provides insights for financial market participants to make better portfolio allocation decisions. It is also increasingly important to understand the volatility transmission mechanism across these markets to provide policymakers and regulatory bodies with guidance to eliminate the negative impact of cryptocurrency's volatility on the stability of financial markets.
Quang Tung Thai, Namseok Ko, Sung Hyuk Byun, Sun-Me Kim
Blockchain technology allows public parties to agree on a common state without relying on a central authority. Despite it brings many innovative use cases, the technology is still in its early stage that needs improving on many aspects. One of the issues is to deliver blockchain data more efficiently. Named Data Networking (NDN), a new network paradigm, is designed to make content distribution with ease by enabling in-network caching and built-in multicasting, which blockchain technologies can take advantage. Moreover, blockchain may contribute to extending NDN application ecosystems including decentralized applications. Therefore, it is instrumental to have a working blockchain system that runs on NDN platform to supports its research and development. In this work, we design and implement an NDN-based Ethereum blockchain platform. We propose new protocols for propagating blockchain data making full use of NDN features for the delivery of transactions and blocks. Our experiments show that the distribution of blockchain data in NDN is more efficient than that of IP network. The latency of block delivery is also reduced, which in turn supports tuning blockchain parameter for better security. Our developed blockchain client is freely distributed as an open-source project. We hope that it can provide a platform to foster blockchain research on NDN in the future.
Interoperable and secure data management techniques are fundamental for most of large-scale Structural Health Monitoring (SHM) systems. Indeed, given the relevance of SHM critical measurements, data integrity must be protected against tampering or falsifications. In this paper, we propose a four-layer SHM architecture that allows to build an effective data pipeline from sensors to consumer applications, passing through the cloud. The architecture is built on top of the MODRON platform and exploits the recent advances of the W3C Web of Things (WoT) standard for interoperability. We then discuss how third-party services can take benefit of the W3C WoT architecture to retrieve the SHM critical data and to publish them on the Ethereum Blockchain through an SHM-specific Smart Contract, for data protection and traceability purposes. We test the effectiveness of the Smart Contract implementation in terms of latency and costs under simulated workloads.