Blockchain Papers

Richard Hobeck, Christopher Klinkmüller, H. M. N. Dilum Bandara, Ingo Weber · 5 authors

No abstract is available for this record.

Lingyu Bian, Linlin Zhang, Kai Zhao, Hao Wang · 5 authors

In recent years, the rapid development of blockchain technology has attracted much attention from people around the world. Scammers take advantage of the pseudo-anonymity of blockchain to implement financial fraud. The Ponzi scheme, one of the main scam methods, has defrauded investors of large amounts of money, thereby harming their interests and hindering the application of blockchain. Unfortunately, the current detection technology typically largely relies on the source code of the contract or uses a single feature which does not fully represent the contract characteristics. In such a case, the detection of Ponzi schemes with high efficiency becomes urgent. In this paper, we propose an image-based scam detection method using an attention capsule network (SE-CapsNet) focused on Ethereum. The sequence of bytecode, the opcode frequency, and the application binary interface (ABI) call are extracted as features from the contract bytecode and ABI, further converted into grayscale images, and then mapped into three color channels to generate RGB images, which are used as the input of the model for detecting the Ponzi scheme contract. In addition, we employ fancy PCA for data augmentation to reduce the impact of imbalanced data on the detection results. Experimental results show that the image-based detection method using deep learning models can effectively detect contracts before transactions occur. Among them, our proposed SE-CapsNet obtains great detection results, with an F1 score of 98.38%.

Jingqiao Xu

A blockchain is a distributed ledger in which participants who do not fully trust each other agree on the ledger’s content by running a consensus algorithm. It has been more popular and mature in recent years. Smart contracts on the blockchain system are usually redundantly executed by a large number of nodes for the purpose of verification, which can result in a large waste of computation. The waste is especially significant when the smart contracts are heavy-duty. The problem of reducing the computation has attracted a lot of interest from both the research community and the industry. In this creative component, we present a game theoretic design for efficient execution of heavy-duty smart contracts, and develop a simulator to implement the design and evaluate its performance in a large-scale blockchain system that simulates Ethereum. The simulator is built based on BlockSim, an emerging general-purpose blockchain simulator, but has enhanced it with detailed simulation of the heavy-duty smart contract protocol. The simulation results demonstrate the efficacy and efficiency of our design.

Mohammad Saidur Rahman, Ibrahim Khalil, Mohammed Atiquzzaman

Drones, or unmanned aerial vehicles, can be used for commercial services such as short-distance delivery. In order to ensure quality services, multiple drone-based delivery service providers can be employed in delivery service systems. In this article, we address two very important and unexplored challenges of employing drones in delivery services. First, involving multiple drones from different service providers elevates the chance of collision during flights. Second, drones may hamper the privacy of citizens by unauthorized access to private and restricted areas. In order to solve the aforementioned issues, we propose a blockchain-based policy enforcement mechanism in the drone-based delivery service systems. At first, the mechanism will set policies to establish pre-allocated flight paths for different drones at different times to avoid collisions, and ensure the privacy of citizens by restricting their access to unauthorized areas. Later, the blockchain will enforce the policies to monitor compliance of the drone flights and identify non-compliant drone services to penalize corresponding service providers. We simulate a virtual drone-based delivery system with the Ethereum blockchain platform and examine the performance and feasibility of our proposed mechanism.

Deoksang Lee, Minseok Song

Health information exchange (HIE) refers to the integrated management and secure sharing of health information among healthcare entities. HIE improves healthcare quality and streamline healthcare administrative work. These advantages have propelled health-care stakeholders to implement HIE. However, challenged by issues such as security, privacy, and costs, HIE is not widespread. Recent studies have suggested blockchain-based HIE for solving security and privacy issues. Unfortunately, existing blockchain-based HIE studies do not consider the privacy issues caused by analyzing senders and receivers of transactions in the blockchain. In this work, we suggest MEXchange, a novel blockchain-based privacypreserving HIE that prevents the privacy issue by obscuring the sender and concealing receiver addresses. We propose smart contracts and workflow that use ring signature and stealth address for blockchainbased HIE. Software components and implementation of MEXchange on the Ethereum private network are discussed. We evaluate MEXchange quantitatively by measuring the transaction latency and throughput of exchanging. Also, we evaluate MEXchange qualitatively using the requirements of the Office of National Coordinator for Health Information Technology (ONC). Moreover, we proceed threat modeling based on STRIDE. Finally, we compare MEXchange with Ancile, FHIRChain, Integrating the Healthcare Enterprise Cross-Enterprise Document Sharing (IHE XDS), and MedRec. The MEXchange lowers barriers to the application of blockchain-based HIE systems by mitigating privacy and security issues among healthcare stakeholders.

Mahdi Ghaemi Asl, Elie Bouri, Sahar Darehshiri, David Gabauer

No abstract is available for this record.

Mattias Kallman

With the mass expansion of Internet of Things (IoT) in industry and consumer life, IoT security has become a focal point of research and development. New technologies are enabling unprecedented methods of developing and securing IoT devices. This thesis focuses on studying and applying Web 3.0 technologies in an IoT device and service context while addressing IoT security vulnerabilities through the use of good security design practices. Through the application of Web 3.0 technologies this thesis illustrates the advantages and disadvantages that these technologies offer. The practi- cal implementation utilizes a custom Ethereum based security protocol that enables an IoT device to use a decentralized data network as its dedicated backend infrastructure. The results of the implementation will be analyzed through the lens of security and practicality.

Hyo-Jong Kim, Han Kun-Hee, Seung-Soo Shin

No abstract is available for this record.

Farimah Poursafaei, Reihaneh Rabbany, Željko Žilić

No abstract is available for this record.

Zhiyuan Xue, Miao Wang, Qiuyue Zhang, Yunfeng Zhang · 5 authors

Blockchain is a decentralized distributed ledger technology. The public chain represented by Bitcoin and Ethereum only realizes the limited anonymity of user identity, and the transaction amount is open to the whole network, resulting in user privacy leakage. Based on the existing anonymous technology, the concealment of the sender, receiver, amount of the transaction, and does not disclose any information, which makes the supervision difficult. Therefore, the design of blockchain scheme with privacy protection and supervision functions is of great significance. In this paper, a blockchain transaction model with both privacy and supervision function is proposed. It uses probability encryption to realize the hiding of the true identity of the blockchain transaction, and uses the commitment scheme and zero-knowledge proof technology to realize the privacy protection and guarantee legitimacy verification of the transaction. With the use of encryption technology, the regulators can supervise blockchain transactions without storing the users' information, which greatly reduces the pressure on storage, computing and key management. In addition, it does not rely on specific consensus mechanism and can be used as an independent module. The security performance analysis shows that the proposed scheme has great practicability and has potential application in many fields.

Authors unavailable

Blockchain is an emerging technology that has many uses and applications among many industries such as banking, education, and tourism. It has proven over time to be more cryptographically secure than traditional databases. Many people confuse Bitcoin with Blockchain. Because of the considerable value of Bitcoins, people have the perception that blockchain technology requires large computing infrastructure and power due to CPU bottleneck challenges. This paper presents the process used in testing blockchain technology performance on a virtual machine by focusing on benchmarking workloads like CPUHeavy using Ethereum blockchain and comparing two different algorithm sorts, Quick and bubble. The results of the testing indicate that blockchain workloads can be performed on smaller machines with very little CPU bottlenecks. In addition, performance test outcomes found that the CPUHeavy and Quicksort was more superior.

Marlene Kuhn, Felix Funk, Jörg Franke

The automotive value chain comprises a complex manufacturing network, which encompasses several departments, companies, and even countries. In the age of electrification and autonomous driving, the quality and transparency requirements are rising, in particular for electric and electronic components, which contribute to safety-critical functionalities. In this research, we analyze the traceability requirements and liability implications for the automotive manufacturing network. A key component in preventing safety and quality deficiencies in manufacturing processes is a state-of-the-art traceability system. Accordingly, we propose a blockchain-based traceability architecture to achieve the aspired level of transparency and process security. The proposed blockchain architecture processes manufacturing data entries and defines blockchain nodes, access, as well as consensus algorithm and transaction logic. An Ethereum-based blockchain demonstrator validates the architecture by implementing the logic for automotive product configuration and process sequencing based on the semi-fungible ERC 1155 token, the proof of authority consensus, and an automotive product token smart contract.

Munum Butt

No abstract is available for this record.

Hyunsu Mun, Soohyun Kim, Youngseok Lee

No abstract is available for this record.

Przemysław Rodwald

No abstract is available for this record.

Randhir Kumar, Ningrinla Marchang, Rakesh Tripathi

No abstract is available for this record.

Bruce Mizrach

Stable coins are not very stable. Cash collateralized coins are more stable, but the overall failure rate is similar to tokens that are not designed to be stable. USD Coin, Tether and Dai have the largest Ethereum market shares, and they have an average velocity nearly three times higher than M1. Centralized and decentralized exchanges are the most active nodes and largest holders on the blockchain. Four of the top ten tokens have Herfindahl indices higher than the U.S. banking system. Median gas fees for Tether rose more than twelve times over the last two years, and nearly twenty times for USD Coin. Transactions of under 50,000 USD can generally be done more cheaply offchain. 24 hour exchange turnover in Tether is nearly 60 billion USD. This is comparable to the daily volume at the NYSE and eight times the daily flow in money market mutual funds. Narrow bid-ask spreads and depth have attracted HFT participation approaching 50%

AKM Bahalul Haque, Bharat Bhushan

Blockchain gets its name from being a series of blocks that are linked together to form a chain. Once the information has been added to the chain, it cannot be changed. There are several consensus protocols, and each of them is chosen based on the type of blockchain and the system requirements. With the rapid urbanization of the world, several economic, social, and environment-related issues have been raised. Smart cities are an emerging concept that holds the solution to these urban problems. Blockchain is such an innovation that can promote the development of smart cities. Along with its application in the internet of things, smart cities, and logistics, blockchain truly is state-of-the-art technology. Here, the authors aim to provide an in-depth look into this relatively new technology, beginning with blockchain's fundamentals and then covering the applications, issues, and future scope.

Alon Benhaim, Brett Hemenway, Gerry Tsoukalas

In the high-stakes race to develop more scalable blockchains, some platforms (Binance, Cosmos, EOS, TRON, etc.) have adopted committee-based consensus (CBC) protocols, whereby the blockchain's record-keeping rights are entrusted to a committee of elected block producers. In theory, the smaller the committee, the faster the blockchain can reach consensus and the more it can scale. What's less clear, is whether such protocols ensure that honest committees can be consistently elected, given blockchain users typically have limited information on who to vote for. We show that the approval voting mechanism underlying most CBC protocols is complex and can lead to intractable optimal voting strategies. We empirically characterize some simpler intuitive voting strategies that users tend to resort to in practice and prove that these nonetheless converge to optimality exponentially quickly in the number of voters. Exponential convergence ensures that despite its complexity, CBC exhibits robustness and has some efficiency advantages over more popular staked-weighted lottery protocols currently underlying many prominent blockchains such as Ethereum.

Dunjie Zhang, Jinyin Chen, Xiaosong Lu

With the popularity of blockchain technology, the financial security issues of blockchain transaction networks have become increasingly serious. Phishing scam detection methods will protect possible victims and build a healthier blockchain ecosystem. Usually, the existing works define phishing scam detection as a node classification task by learning the potential features of users through graph embedding methods such as random walk or graph neural network (GNN). However, these detection methods are suffered from high complexity due to the large scale of the blockchain transaction network, ignoring temporal information of the transaction. Addressing this problem, we defined the transaction pattern graphs for users and transformed the phishing scam detection into a graph classification task. To extract richer information from the input graph, we proposed a multi-channel graph classification model (MCGC) with multiple feature extraction channels for GNN. The transaction pattern graphs and MCGC are more able to detect potential phishing scammers by extracting the transaction pattern features of the target users. Extensive experiments on seven benchmark and Ethereum datasets demonstrate that the proposed MCGC can not only achieve state-of-the-art performance in the graph classification task but also achieve effective phishing scam detection based on the target users' transaction pattern graphs.

Nikolay Ivanov, Hanqing Guo, Qiben Yan

The developers of Ethereum smart contracts often implement administrating patterns, such as censoring certain users, creating or destroying balances on demand, destroying smart contracts, or injecting arbitrary code. These routines turn an ERC20 token into an administrated token - the type of Ethereum smart contract that we scrutinize in this research. We discover that many smart contracts are administrated, and the owners of these tokens carry lesser social and legal responsibilities compared to the traditional centralized actors that those tokens intend to disrupt. This entails two major problems: a) the owners of the tokens have the ability to quickly steal all the funds and disappear from the market; and b) if the private key of the owner's account is stolen, all the assets might immediately turn into the property of the attacker. We develop a pattern recognition framework based on 9 syntactic features characterizing administrated ERC20 tokens, which we use to analyze existing smart contracts deployed on Ethereum Mainnet. Our analysis of 84,062 unique Ethereum smart contracts reveals that nearly 58% of them are administrated ERC20 tokens, which accounts for almost 90% of all ERC20 tokens deployed on Ethereum. To protect users from the frivolousness of unregulated token owners without depriving the ability of these owners to properly manage their tokens, we introduce SafelyAdministrated - a library that enforces a responsible ownership and management of ERC20 tokens. The library introduces three mechanisms: deferred maintenance, board of trustees and safe pause. We implement and test SafelyAdministrated in the form of Solidity abstract contract, which is ready to be used by the next generation of safely administrated ERC20 tokens.

Jiacheng Liang, Songze Li, Cao, Bochuan, Wensi Jiang · 5 authors

We propose OmniLytics, a blockchain-based secure data trading marketplace for machine learning applications. Utilizing OmniLytics, many distributed data owners can contribute their private data to collectively train an ML model requested by some model owners, and receive compensation for data contribution. OmniLytics enables such model training while simultaneously providing 1) model security against curious data owners; 2) data security against the curious model and data owners; 3) resilience to malicious data owners who provide faulty results to poison model training; and 4) resilience to malicious model owners who intend to evade payment. OmniLytics is implemented as a blockchain smart contract to guarantee the atomicity of payment. In OmniLytics, a model owner splits its model into the private and public parts and publishes the public part on the contract. Through the execution of the contract, the participating data owners securely aggregate their locally trained models to update the model owner's public model and receive reimbursement through the contract. We implement a working prototype of OmniLytics on Ethereum blockchain and perform extensive experiments to measure its gas cost, execution time, and model quality under various parameter combinations. For training a CNN on the MNIST dataset, the MO is able to boost its model accuracy from 62% to 83% within 500ms in blockchain processing time.This demonstrates the effectiveness of OmniLytics for practical deployment.

Neta Elad, Sophie Rain, Neil Immerman, Laura Kovács · 5 authors

Abstract Some of the most significant high-level properties of currencies are the sums of certain account balances. Properties of such sums can ensure the integrity of currencies and transactions. For example, the sum of balances should not be changed by a transfer operation. Currencies manipulated by code present a verification challenge to mathematically prove their integrity by reasoning about computer programs that operate over them, e.g., in Solidity. The ability to reason about sums is essential: even the simplest ERC-20 token standard of the Ethereum community provides a way to access the total supply of balances. Unfortunately, reasoning about code written against this interface is non-trivial: the number of addresses is unbounded, and establishing global invariants like the preservation of the sum of the balances by operations like transfer requires higher-order reasoning. In particular, automated reasoners do not provide ways to specify summations of arbitrary length. In this paper, we present a generalization of first-order logic which can express the unbounded sum of balances. We prove the decidablity of one of our extensions and the undecidability of a slightly richer one. We introduce first-order encodings to automate reasoning over software transitions with summations. We demonstrate the applicability of our results by using SMT solvers and first-order provers for validating the correctness of common transitions in smart contracts.

Franck Cassez

The Deposit Smart Contract (DSC) is an instrumental component of the Ethereum 2.0 Phase 0 infrastructure. We have developed the first machine-checkable version of the incremental Merkle tree algorithm used in the DSC. We present our new and original correctness proof of the algorithm along with the Dafny machine-checkable version. The main results are: 1) a new proof of total correctness; 2) a software artefact with the proof in the form of the complete Dafny code base and 3) new provably correct optimisations of the algorithm.