Blockchain enables peer-to-peer transactions in cyberspace without a trusted third party. The rapid growth of Ethereum and smart contract blockchains generally calls for well-designed Transaction Fee Mechanisms (TFMs) to allocate limited storage and computation resources. However, existing research on TFMs must consider the waiting time for transactions, which is essential for computer security and economic efficiency. Integrating data from the Ethereum blockchain and memory pool (mempool), we explore how two types of events affect transaction latency. First, we apply regression discontinuity design (RDD) to study the causal inference of the Merge, the most recent significant upgrade of Ethereum. Our results show that the Merge significantly reduces the long waiting time, network loads, and market congestion. In addition, we verify our results' robustness by inspecting other compounding factors, such as censorship and unobserved delays of transactions via private changes. Second, examining three major protocol changes during the merge, we identify block interval shortening as the most plausible cause for our empirical results. Furthermore, in a mathematical model, we show block interval as a unique mechanism design choice for EIP1559 TFM to achieve better security and efficiency, generally applicable to the market congestion caused by demand surges. Finally, we apply time series analysis to research the interaction of Non-Fungible token (NFT) drops and market congestion using Facebook Prophet, an open-source algorithm for generating time-series models. Our study identified NFT drops as a unique source of market congestion -- holiday effects -- beyond trend and season effects. Finally, we envision three future research directions of TFM.
JesĂșs Rosa-Bilbao, Juan Boubeta-ÂPuig, Adrian Rutle
Internet of Things (IoT) is made up of millions of devices generating large amounts of heterogeneous data from multiple sources. These devices can be from multiple manufacturers which makes their use in terms of data acquisition, processing, analysis and actions on these data challenging. Additionally, all these data must be analyzed and correlated in real time for the early detection of situations of interest (complex events) and subsequent decision making. These complex events must be able to automatically trigger decisions and be stored in a secure, immutable and accessible way. In this context, Event-Driven Applications (EDAs) are a solution to meet these needs, however, developing such applications requires vast knowledge in certain technologies. To address these challenges, an EDA is proposed in this paper to integrate Complex Event Processing (CEP) and blockchain through the low-code paradigm. This proposal allows for the development of EDAs in a user-friendly way. These applications make it possible to integrate IoT devices from multiple manufacturers and with different data formats together with CEP technology for complex event detection and blockchain for secure, immutable and accessible event storage. To demonstrate the feasibility, the architecture was applied and evaluated in a case study related to measuring and acting on air quality using IoT devices that measure different pollutants and factors such as temperature, humidity and wind. The results show that the graphically designed EDAs facilitate the real-time analysis of the collected IoT data via a CEP engine, whose outcome is transparently and automatically registered in a blockchain network.
Farhana Javed, Josep ManguesâBafalluy, Engin Zeydan
This poster presents a use case for smart contract-based inter-provider agreements and Service Level Agreement (SLA) monitoring for 6G networks. We use chainlink oracle and InterPlanetary File System (IPFS) to monitor SLA data logs. We also provide experimental evaluations of two approaches: raw data log access in IPFS and chainlink-based log access. To understand the performance and feasibility of the proposed approaches on a public blockchain, the proposed framework is deployed on the Ethereum and Polygon testnets to measure the cost and latency for both approaches. We measure the latency as well as the total cost for comparison purposes. The maximum cost observed for the first approach is â 1.4 USD, and the maximum latency observed with the first approach is â4 seconds in the Polygon testnet and 12 ~ 14 seconds in the Ethereum testnet. However, the second approach's latency is 30 ~ 60 seconds.
Secure voting may be a crucial application of blockchain advancement, but guaranteeing the astuteness and protection of voting can be a complex issue. This record proposes a blockchain-based cloud computing appear on the Ethereum Virtual Machine (EVM) trade to address this issue. Our dissidents will utilize savvy contracts to screen vote preparation, but the votes themselves will be put away off-chain in a secure cloud capacity framework. We utilize agreement calculations based on Proof-of-Stake (PoS) measures to guarantee voting preparation choices. This degree guarantees that authorized centers can take part, so to talk, within the preparation of votes, which votes are numbered precisely. Moreover, we propose a novel cryptographic plot that permits for exact numbering of votes whereas ensuring vote mystery. Our appear is outlined to be versatile and successful in arrange to form it reasonable for large-scale voting scenarios. demonstrate. Our comes about show up to supply a flexible and able include for secure voting whereas guaranteeing voting precision and secrecy.
A significant portion of research on distributed ledgers has focused on circumventing the limitations of leader-based blockchains mainly in terms of scalability, decentralization and power consumption. Leaderless architectures based on directed acyclic graphs (DAGs) avoid many of these limitations altogether, but their increased flexibility and performance comes at the cost of increased design complexity, so their potential has remained largely unexplored. Management of write access to these ledgers presents a major challenge because ledger updates may be made in parallel, hence transactions cannot simply be serialised and prioritised according to token fees paid to validators. In this work, we propose an access control scheme for leaderless DAG-based ledgers which is based on consuming credits rather than paying fees in the base token. We outline a general model for this new approach and provide some simulation results showing promising performance boosts.
Anwar Sadad, Muazzam A. Khan, Baraq Ghaleb, Fadia Ali Khan · 7 authors
Blockchain (BC) and Information for Operational and Tactical Analysis (IOTA) are distributed ledgers that record a huge number of transactions in multiple places at the same time using decentralized databases. Both BC and IOTA facilitate Internet-of-Things (IoT) by overcoming the issues related to traditional centralized systems, such as privacy, security, resources cost, performance, and transparency. Still, IoT faces the potential challenges of real-time processing, resource management, and storage services. Edge computing (EC) has been introduced to tackle the underlying challenges of IoT by providing real-time processing, resource management, and storage services nearer to IoT devices on the network's edge. To make EC more efficient and effective, solutions using BC and IOTA have been devoted to this area. However, BC and IOTA came with their pitfalls. This survey outlines the pitfalls of BC and IOTA in EC and provides research directions to be investigated further.
Zhongming Yao, Junchang Xin, Kun Hao, Zhiqiong Wang · 5 authors
Blockchain has become increasingly popular for data management in recent years. However, the existing blockchain systems lack efficient semantic queries, particularly keyword queries. To address this issue, we propose a learned-index-based semantic keyword query architecture on blockchain. First, our architecture records data semantics information to support semantic keyword queries. Second, we establish the lookup table index for semantic information among blocks and the block-level recursive model index for blocks to improve the query efficiency. We store the lookup table in the extended block headers to maintain the resultâs completeness, and we store recursive model indexes off chain to optimize the maintenance efficiency. Third, we propose a verifiable query algorithm based on our proposed architecture to maintain the resultâs correctness. Finally, the experimental results show that combining the lookup table and the learned index effectively improves the query efficiency on blockchain.
Blockchain interoperability promotes value delivery, application expansion, and ecological compatibility across heterogeneous blockchain systems. However, the contract framework and virtual machine construction in these systems are significantly different, and crosschaining becomes a challenging issue for system universality and compatibility. Starting from this problem, in this study, we propose VM-Studio, a crosschain smart contract verification and execution scheme to migrate the virtual machines (VMs) from the origin blockchain to the target blockchain. In our scheme, the migrated VMs are loaded as independent components enclosed in containers. We also design a unified system schedule to enable VM-Studio to allocate transactions into different containers. Loaded with origin blockchain VMs, these containers can accordingly solve crosschain transaction execution and smart contract verification. We implement VM-Studio and evaluate the transaction execution performance in the origin environment with multiple blockchains and the container environment. Experiment results demonstrate that VM-Studio achieves broad universality without compromising the execution performance of original blockchain transactions.
Blockchain has attracted significant attention in recent years due to its potential to revolutionize various industries by providing trustlessness. To comprehensively examine blockchain systems, this article presents both a macro-level overview on the most popular blockchain systems, and a micro-level analysis on a general blockchain framework and its crucial components. The macro-level exploration provides a big picture on the endeavors made by blockchain professionals over the years to enhance the blockchain performance while the micro-level investigation details the blockchain building blocks for deep technology comprehension. More specifically, this article introduces a general modular blockchain analytic framework that decomposes a blockchain system into interacting modules and then examines the major modules to cover the essential blockchain components of network, consensus, and distributed ledger at the micro-level. The framework as well as the modular analysis jointly build a foundation for designing scalable, flexible, and application-adaptive blockchains that can meet diverse requirements. Additionally, this article explores popular technologies that can be integrated with blockchain to expand functionality and highlights major challenges. Such a study provides critical insights to overcome the obstacles in designing novel blockchain systems and facilitates the further development of blockchain as a digital infrastructure to service new applications.
Igor Y. Mazurok, Yevhen Leonchyk, Sergii Grybniak, Alisa Vorokhta · 5 authors
Decentralized platforms like blockchain have been attracting significant attention in recent years, especially in the context of financial and payment systems. They are designed to provide a transparent, secure, and reliable environment for digital transactions without the need for a central authority. The core of a decentralized platform like blockchain is a consensus layer that allows all participants (called Workers), who properly operate and follow all network protocols and have access to the same state of the distributed ledger, to coordinate their actions and arrive at the same decisions. However, some Workers may be temporarily offline attheir own discretion, without any confirmation, or their work may be faulty due to technical circumstances, resulting in unpredictablebehavior. The goal of this article is to present an approach for multi-objective optimizing of Byzantine fault tolerance (BFT)-basedconsensus protocols, to reduce the impact on the network of faulty participants. Two criteria were considered â minimization of thenumber of sent service messages, and maximization of the mathematical expectation of the number of produced blocks. The result isa method to determine the optimal committee size and distribution of Workers, depending on their total number in the network andthe expected proportion of Byzantine faulty nodes. All protocol amendments presented in this work are tested with corresponding simulation models and have demonstrated notable enhancements in the performance of the system and decreased the load on network nodes. These improvements will be implemented to the consensus protocol Gozalandia on the Waterfall platform, enhancing itsoverall reliability, performance, and security. In addition, the presented optimizing algorithm can be applied to a wide range of consensus protocols in blockchains, where blocks must be signed by randomly selected committees to confirm their validity.
Consensus mechanisms play a critical role in blockchain networks, ensuring that all participants agree on the state of the distributed ledger. However, existing consensus mechanisms have limitations in terms of efficiency, security, and decentralization. In this research paper, we propose a Hybrid Consensus Mechanism (HCM) that combines the advantages of Delegated Proof of Stake (DPoS), Practical Byzantine Fault Tolerance (PBFT), and Proof of Elapsed Time (PoET) to address these limitations. HCM uses a set of trusted validators (delegates) similar to DPoS, who participate in a PBFT-like consensus protocol to reach agreement on the state of the ledger. PoET is used to randomly select the leader for each consensus round, preventing the concentration of power. HCM also introduces a dynamic delegation mechanism and sharding technique to enhance fairness, resilience, and scalability in blockchain networks. We provide detailed technical insights, backed by underlying data, to illustrate the effectiveness of HCM in achieving efficient and secure consensus.
Given that reliable cloud quantum computers are becoming closer to reality, the concept of delegation of quantum computations and its verifiability is of central interest. Many models have been proposed, each with specific strengths and weaknesses. Here, we put forth a new model where the client trusts only its classical processing, makes no computational assumptions, and interacts with a quantum server in a single round. In addition, during a set-up phase, the client specifies the size $n$ of the computation and receives an untrusted, off-the-shelf (OTS) quantum device that is used to report the outcome of a single measurement. We show how to delegate polynomial-time quantum computations in the OTS model. This also yields an interactive proof system for all of QMA, which, furthermore, we show can be accomplished in statistical zero-knowledge. This provides the first relativistic (one-round), two-prover zero-knowledge proof system for QMA. As a proof approach, we provide a new self-test for n EPR pairs using only constant-sized Pauli measurements, and show how it provides a new avenue for the use of simulatable codes for local Hamiltonian verification. Along the way, we also provide an enhanced version of a well-known stability result due to Gowers and Hatami and show how it completes a common argument used in self-testing.
As coin-based rewards dwindle, transaction fees play an important role as mining incentives in Bitcoin. In this paper, we propose a novel mechanism called Efficient Dynamic Transaction Storage (EDTS) for dynamically allocating transactions among blocks to achieve efficient storage utilization. By leveraging a combination of Cuckoo Filter and Dynamic Transaction Storage (DTS) strategies, EDTS is able to improve the scalability while remaining sustainable even after the Bitcoin enters a transaction-fee regime. In addition to preventing deviant mining behaviors under the transaction-fee regime, EDTS can also provide differentiated transmission priorities based on transaction fees while allowing the investors to engage in pledging more transaction fees. In EDTS, we applied the multi-objective optimization algorithm U-NSGA-III to find the best DTS strategy and its corresponding attributes. Experimental results show that the EDTS mechanism together with the optimized DTS strategy can achieve a throughput of 325.3 TPS. The experimental results reveal that the scalability improvement of EDTS is superior to the performance of Bitcoin NG, which is the best known on-chain scaling solution, while maintaining the sustainability under the transaction-fee regime.
Miguel Pincheira, Elena Donini, Massimo Vecchio, Raffaele Giaffreda
Blockchain is currently a core technology for developing new types of decentralized applications. With the unique properties of blockchain, unique challenges and characteristics are introduced to the system. Among these characteristics, the infrastructure costs and benefits of the system are critical to evaluate the feasibility of any system and have yet to be addressed in the current literature. This work presents a framework for evaluating blockchain applicationsâ infrastructure costs and benefits. The framework includes a taxonomy to classify the related transactions, a model to evaluate the infrastructure costs and benefits in applications using public or private blockchains, and a methodology to guide the use of the model. The model is based on simple parameters that describe the systems, and the methodology helps to identify and estimate these parameters at any stage of the application life cycle. We quantitatively analyze three real use cases to demonstrate the frameworkâs merit. The analyses highlight the modelâs accuracy by achieving the same results presented in the use cases. Furthermore, the use-case analyses emphasize the frameworkâs potential to evaluate different scenarios across the entire life cycle of blockchain-based applications.
Blockchain is a decentralized, shared ledger that aggregates blocks of data in a factual data structure in chronological order using a chain structure. Two hundred sixty thousand tokens, or 98% of the around 2.5 million smart contracts in Ethereum network, are ERC-20 tokens. The ERC20 standard specifies constructors for token contracts that establish and initialize the contract state. The Ethereum wallet and Ethereum decentralized, centralized applications can access tokens through these standard interfaces. Security vulnerabilities in ERC-20 have drawn a lot of attention lately in recent years. This paper summarizes some basic security vulnerabilities and suggests avoiding multiple withdrawal attacks. Tokens can be used to support dApps, access blockchain services, trade, and obtain voting rights. Various tokens exist depending on their properties and use cases, including governance, utility, security, transaction, and platform tokens. Tokens can be sorted as fungible tokens and non-fungible tokens. Tokens that can be fungible are identical, divisible, and can be instead of money. Non-fungible tokens have a single owner and are unique.
Gartnerâs hype cycle of technology famously progresses from the âpeak of inflated expectationsâ to the âplateau of productivityâ via the âtrough of disillusionmentâ. Accounting researchers and practitionersâlike researchers and practitioners in many other fieldsâhave jumped onto the blockchain bandwagon for fear of missing out on what has been hailed as a world changing technology. Unfortunately, there is a pervasive lack of understanding of what blockchain is, and misconceptions about what it can do. A fundamental problem is that blockchain was derived from bitcoin and there is a great deal of difficulty in defining what blockchain is, and how suitable the methodology for a trustless, public cybercurrency application is to a public blockchain between trusted partners. It is time, we believe, to look at blockchain in accounting with more objectivity. We undertake a detailed exploration of blockchain and identify several key factors that will defines the uses of this technology, namely, the distinction between public and private blockchains and the importance of processing costs as a validating mechanism.
Novak BoĆĄkov, Ari Trachtenberg, David Starobinski
The problem of data synchronization arises in networked applications that require some measure of consistency. Indeed data synchronization approaches have demonstrated a significant potential for improving performance in various applications ranging from distributed ledgers to fog-enabled storage offloading for IoT. Although several protocols for data sets synchronization have been proposed over the years, there is currently no widespread utility implementing them, unlike the popular Rsync utility available for file synchronization. To that end, we describe a new middleware called GenSync that abstracts the subtleties of the state-of-the-art data synchronization protocols, allows users to choose protocols based on a comparative evaluation under realistic system conditions, and seamlessly integrate protocols in existing applications through a public API. We showcase GenSync through a case study, in which we integrate it into one of the world's largest wireless emulators and compare the performance of its included protocols.
Non-fungible tokens (NFTs) have been attracting the interest of both technical and non-technical parties, including collectors and traders, among others. The number of transactions in NFTs surpassed $50 billion in 2022. Blockchain technology's advantages as a distributed, immutable, and transparent database make it ideal for verifying the ownership of digital goods created by their producers. On the other hand, high computation and transaction costs are known disadvantages of public blockchain networks like Ethereum V1, used in NFT marketplaces. To address these inefficiencies, other public blockchain systems have emerged as replacements for NFT marketplaces, each with its own unique properties. When planning such an NFT exchange, it is vital, but not trivial, to select the most appropriate public blockchain platform. In this work, we make two contributions to support this decision. In this paper, we present IntelliChain , a self-adaptive framework that can predict the best optimal transaction fees (also known as a gas fee) for blockchain to reduce the errors and also an ability to switch the public blockchain-based dynamic needs such as transaction fees and stability of the network.
Everything is digitalized in the digital age, including the SSLC, HSC, and academic certificates, which are sent to students and digitalized at educational establishments. Students have difficulty maintaining their degree credentials. Organizations and institutions find it difficult and time-consuming to verify certificates. By storing the certificate in the Blockchain system, our proposal will aid in its security. Advanced certificates are first made from the paper certificates. The certificate's hash code esteem is made utilizing the turbulent calculation. From that point onward, the confirmations are saved in Blockchain. Moreover, these certificates are confirmed through the versatile application.
Blockchain technology has gained momentum due to its immutability and transparency. Several blockchain platforms, each with different consensus protocols, have been proposed. However, choosing and configuring such a platform is a non-trivial task. Numerous benchmarking tools have been introduced to test the performance of blockchain solutions. Yet, these tools are often limited to specific blockchain platforms or require complex configurations. Moreover, they tend to focus on one-off batch evaluation models, which may not be ideal for longer-running instances under continuous workloads. In this work, we presentBlockCompass, an all-inclusive blockchain benchmarking tool that can be easily configured and extended. We demonstrate howBlockCompasscan evaluate the performance of various blockchain platforms and configurations, including Ethereum Proof-of-Authority, Ethereum Proof-of-Work, Hyperledger Fabric Raft, Hyperledger Sawtooth with Proof-of-Elapsed-Time, Practical Byzantine Fault Tolerance, and Raft consensus algorithms, against workloads that continuously fluctuate over time. We show how continuous transactional workloads may be more appropriate than batch workloads in capturing certain stressful events for the system. Finally, we present the results of a usability study about the convenience and effectiveness offered byBlockCompassin blockchain benchmarking.
Kashif Mehboob Khan, Aabira Fahim, Darakhshan M. Saleem, Marvi Jokhio
With the emerging employment of blockchains in different fields a need for blockchain intercommunication has arisen but there is no set standard yet for blockchain development, adoption and implementation due to which its interoperability has become a challenge. Interoperability refers to the mechanism of exchange and utilization of information between two software or computer systems etc. In blockchain, interoperability is the process of data creation, transfer and storage between two blockchains or blockchain applications. Blockchain interoperability is complex as every blockchain may have a different implementation platform and protocol for consensus mechanism. Bringing together two different blockchains and enabling communication between them without modifying their underlying implementation structure is a challenge today. There has been ongoing research in this domain to achieve interoperability in blockchains effectively. Its importance is evident from the fact that blockchain interoperability is vital for promoting scalability which is another research challenge presently. Apart from this, blockchain interoperability also promotes data privacy, application flexibility and portability and provides new opportunities in business. In this paper we have discussed in detail the three approaches and the solutions they provide for implementing blockchain interoperability. An empirical based analysis has been used to strengthen our methodology, which takes into consideration the selection of known & established blockchain network with state-of-the-art tools and technology. In order to have seamless communication across different chains, light clients (representing the respective chain) have been enabled to store each otherâs information such as protocol version etc. In this way, the handshake between both the chain has resulted in a successful IBC (Inter Blockchain Communication) inside the Cosmos environment. It is concluded that although blockchain interoperability is being implemented today, this implementation is highly restricted to specific organizations or software tools. Moreover interoperability between two different blockchains is still an ongoing challenge. This study will assist the future work in the domain of blockchain interoperability as it makes the understanding and implementation of blockchain interoperability easier.