Architectural design contexts contain a set of factors that greatly influence software application development. Among them, organizational design contexts consist of high-level company concerns and how it is structured, for example, stakeholders and development schedules heavily impacting design considerations. The Decentralized Autonomous Organization (DAO), as a vital concept in the Web3 space, represents an organization constructed by automatically executed rules, such as via smart contracts, holding features of the permissionless committee, transparent proposals, and fair contribution by participated stakeholders. In this work, we conduct a systematic literature review of existing DAO literature to summarize its structural features, benefits and challenges, and potential development directions in the context of Web3 applications.
Efficient data storage and query processing systems play a vital role in many different research areas. Blockchain technology and distributed ledgers attract massive attention and trigger multiple projects in various industries. Nevertheless, blockchain still lacks the features of a Database Management System (DBMS or simply databases), such as high throughput, low latency, and high capacity. For that purpose, there have been many proposed approaches for handling data storage and query processing solutions in the blockchain. This paper presents a complete overview of many different DBMS types and how these systems can be used to implement, enhance, and further improve blockchain technology. More concretely, we give an overview of 10 transactional, an extensive overview of 14 analytical, 9 hybrids, i.e., translytical, and 13 blockchain DBMSs. We explain how database technology has influenced the development of blockchain technology by unlocking different features, such as Atomicity, Consistency, Isolation, and Durability (ACID), transaction consistency, rich queries, real-time analysis, and low latency. Using a relaxation approach analogous to the one used to prove the Consistency, Availability, Partition tolerance (CAP)-theorem, we postulate a “Decentralization, Consistency, and Scalability (DCS)-satisfiability conjecture” and give concrete strategies for achieving the relaxed DCS conditions. We also provide an overview of the different DBMSs, emphasizing their architecture, storage manager, query processing, and implementation.
In this work we combine Delegated Proof of Stake (DPoS) consensus technique with multiple entry Practical Byzantine Fault Tolerant voting in a permissioned blockchain network. Voting is organized in rounds that contain a number of PBFT consensus cycles. Nodes with low stake are forced to leave at the end of current round and may return to a new round when they repurchase the stake tokens, while nodes with sufficient stake may leave the network temporarily at the completion of current round due to mobility. We consider multiple DPoS classes based on node's initial stake and probability of truthful voting, and model their behavior using embedded Markov Chain which corresponds to a Semi Markov Process (SMP). We show that probability of reaching consensus is higher when rounds are shorter and/or there are more nodes in the network. In addition, we find that nodes from higher priority classes are mostly excluded from voting due to their mobility, while those from lower priority classes are excluded more often on account of low stake.
As Bitcoin grows, more and more users are choosing to use Bitcoin as a means of transaction. For regulatory purposes, the need for retrieval and analysis of large amounts of bitcoin transaction data is raised. Faced with the problems of high retrieval time and cost overhead of current data retrieval tools, this paper proposes a new regulatory-oriented Bitcoin transaction data organization optimization scheme (BTDM). Firstly, BTDM reduces the index retrieval time by introducing Redis, then optimizes the data retrieval efficiency by using file offset mapping method, and finally reduces the cost of searching by transforming the data structure of transaction hash and bit mapping method. The experimental results show that BTDM has significant advantages in terms of performance and cost compared to other retrieval tools.
Blockchain based decentralized currencies are getting much attention these days and being used widely and deployed commercially, many popular platforms are accepting them as a mode of payment. The most popular among all is Bitcoin (BTC) has achieved great success, but these increased transaction volumes introduced problems like low throughput and high transaction processing time. It's not just with the Bitcoin but also other currencies based on Bitcoin which basically use proof of work principle to register a transaction on distributed ledger also facing similar issues leading to question of scalability of blockchain. This paper focuses on the solutions which can be implemented to make the blockchain scalable.
We study security-latency bounds for Nakamoto consensus, i.e., how secure a block is after it becomes k-deep in the chain. We improve the state-of-the-art bounds by analyzing the race between adversarial and honest chains in three different phases. We find the probability distribution of the growth of the adversarial chains under models similar to those in Guo and Ren (2022) when a target block becomes k-deep in the chain. We analyze certain properties of this race to model each phase with random walks that provide tighter bounds than the existing results. Combining all three phases provides novel upper and lower bounds for blockchains with small$\lambda \Delta $.
Dec 1, 2022·2022 IEEE Intl Conf on Parallel & Distributed Processing with Applications, Big Data & Cloud Computing, Sustainable Computing & Communications, Social Computing & Networking (ISPA/BDCloud/SocialCom/SustainCom)
Can Jiang, Duan-Yang Liu, Xiaoli Zhang, Kun Zhou · 5 authors
In recent years, the Bitcoin blockchain has gained wide attention due to its decentralization and transparency. With the extensive adoptions of the Bitcoin blockchain, its size has reached to 408 GB so far and is still growing, which significantly degrades its scalability. Besides, the bootstrap process for newly joining nodes is quite slow and costly due to the huge communication and computation overhead. In the paper, we devise a full-fledged solution that not only improves the scalability of the Bitcoin blockchain, but also accelerates the state synchronization of the Bitcoin blockchain. We adopt IPFS (Inter Planetary File System), a trusted off-chain storage platform, to amortize the storage pressure of the Bitcoin full nodes. Moreover, we present snapshot blocks to enable secure and fast synchronization of UTXO (Unspent Transaction Outputs) set instead of scanning again from the beginning of the Bitcoin blockchain. Finally, we conduct extensive experiments. The results show that, compared with the official Bitcoin core, the scheme reduces the storage space for Bitcoin full nodes by 97.8% and the synchronization time of new nodes by 81.5%, without breaking the protocols of existing system.
Supporting Non-Fungible Token (NFT) Software Development enables the creation and sale of blockchain-based NFTs backed by unique digital or physical assets. Its value classification is important to justify investment in software development. This study surveys the rapid increase in NFT popularity and proposes a methodology to assess the valuation of an NFT and be able to predict the ultimate success of an NFT. The main influential factors identified in the study are the community and scarcity, our result confirms these two main factors that can affect an NFT's valuation, and this poster paper will look in depth at the correlation between the factors and the value of the NFT and provides the future direction of research.
Dec 1, 2022·2022 IEEE Intl Conf on Parallel & Distributed Processing with Applications, Big Data & Cloud Computing, Sustainable Computing & Communications, Social Computing & Networking (ISPA/BDCloud/SocialCom/SustainCom)
Minghao Fu, Haoran Zhu, Jelena Mišić, Vojislav B. Mišić · 6 authors
Eclipse-based Stake-Bleeding (ESB) attack is a kind of long-range attacks in a Proof-of-Stake (PoS) blockchain system, which can shorten the attack completion time. Researchers have quantitatively analyzed ESB attack but ignoring checkpointing defense technique, which solidifies the history of blockchain and then prevents an adversary to change the blockchain. This paper aims to investigate the capability of the checkpoint-based defense scheme in resisting ESB attack. We develop a Monte Carlo simulator to capture the dynamics of a PoS blockchain system, which is subject to ESB attack and deploys checkpoint-base defense scheme. We also develop the methods for calculating the probability of successful attack and attack profit. This simulator can be applied to evaluate the influence of ESB attack and the checkpointing capability from the perspective of honest verifiers, adversaries and victims. Our experiment results can help enhance PoS blockchain security.
P. Mohan, Vivek Balachandran, Ong Ze Quan, Jas Pang Ze Xin · 5 authors
Blockchain is one of the most promising technology trends that has the potential to be extensively adopted in the education sector. In this work, we investigate the feasibility of utilizing an Ethereum blockchain for developing a trusted frame-work using ERC-721 non-fungible tokens (NFTs) for a Module credit management system – NFT-Merit. In this framework, the NFTs minted by a university represents the module credits issued by its faculty and owned by its students upon satisfying module requirements in the credit management system. Once a student has collected all the NFTs required for graduating the degree, a smart contract automatically generates a degree certificate which can be integrated with the well-known OpenCert formats. With cases of degree fraud on the rise, the current methods of degree issuance and verification are inadequate in this digital age. This research involves the design and development of a web-based decentralized application (dApp) on the Ethereum blockchain test network. The NFT-merit dApp is hosted on the InterPlanetary File System (IPFS) as a decentralized network of nodes instead of a single centralized node to enable redundancy, improve scalability and minimize network bandwidth usage for data access. We perform an extensive analysis of the costs involved in deploying NFT-merit and the duration of minting NFTs. Our experimental results show that minting NFTs in batches would require almost the same time as minting a single NFT in a transaction, whereas the cost savings in the former scenario is more than 22% as compared to the latter.
Decentralized Finance (DeFi) – an ecosystem of financial applications built on top of blockchain technology – has kept powering ahead and attracted a large amount of capital in just a few years. As the core part of the DeFi ecosystem, decentralized lending protocols allow users to become lenders or borrowers in a completely decentralized fashion, such that an individual has complete control over their funds at all times. Collecting, analyzing, and visualizing lending data are crucial as these lending protocols are growing steadily. This paper presents an analysis model for decentralized lending protocols. Our main contributions are as follows. (i) We analyze and compare the top lending protocols; (ii) We present a general model to collect and process a large amount of data from multiple lending protocols in an exact and efficient manner; (iii) We design and implement a lending visualization system with various charts divided into three categories, i.e., lending market overview, token analysis, and user analysis.
Abstract—As fully autonomous ride-hailing services continue to scale, occupant-facing microservices have emerged as a linch- pin for multi-rider resource allocation, real-time commerce, and occupant privacy. In previous frameworks, occupant concurrency engines leveraged ephemeral occupant data and aggregator-based telepresence for conflict resolution, yet trust and transparency of occupant identity remain underexplored. This paper proposes a blockchain-powered approach to occupant identity, enabling de- centralized authentication, payment, and data-sharing flows that are impervious to single-point failures. By registering occupant profiles on a distributed ledger, occupant concurrency logic can verify ride privileges, cost splits, and occupant-lingual disclaimers without storing sensitive occupant data in a central aggregator. We describe how occupant concurrency gates, occupant seat usage, ephemeral occupant camera frames, and aggregator route expansions, while deferring occupant identity and micropayment transactions to a blockchain-based ledger. This method unifies occupant-lingual disclaimers with cryptographic wallet checks, ensuring the occupant sees a transparent log of e-commerce or route negotiations. Preliminary simulation results suggest that decentralized occupant identity reduces aggregator overhead by 25%, while occupant-lingual disclaimers adoption remains high due to ephemeral occupant data policies. We further demonstrate how partial offline fallback can cache occupant ledger proofs, re- syncing only hashed occupant usage logs upon coverage reestablishment. By designing occupant concurrency logic around distributed identity, occupant-lingual expansions—like seat reassignments or multi-tenant microservices—achieve global security invariants across multiple brands, fleets, or regional operators. This paper marks a critical step in bridging occupant concur- rency with blockchain and distributed identity, heralding a future of trust-minimized occupant microservices for the driverless era. Keywords—Blockchain, Distributed Identity, Occupant Con- currency, Ephemeral Data, Occupant-Lingual Disclaimers, Autonomous Ride-Hailing
As technology advances, massive amounts of data in many different formats are produced everywhere. The industries that have fueled the growth of data, including retail, media, finance, healthcare, and education, have produced a tremendously large and complicated collection of data that is known as "big data." On the other hand, a virtual service called cloud computing is utilised for processing, data storage, and data mining in order to maximise flexibility and cut costs. It is assisting society in addressing upcoming issues, including large data management, cyber security, and quality control. Additionally, cutting-edge technologies like distributed ledger technology, artificial intelligence, and many other capabilities are becoming accessible as services thanks to cloud computing. The two most important techniques in the field of information technology. These two IT efforts have the potential to transform every aspect of the company and have an impact on how we analyse data. It’s become popular in research to use the cloud environment for large data analysis. This work attempts to comprehend the Cloud Computing technology in Big Data so as to obtain efficient and quick results. Furthermore, the paper sheds light on the challenges faced in the domain and concludes with the future scope of these technologies.
Henderi Henderi, Qurotul Aini, Irwan Sembiring, Po Abas Sunarya · 6 authors
A variety of information with high research value is produced as an educational asset as a result of the use of various emerging technologies in education. Traditional methods of handling educational resources have emerged. Considering the shortcomings of conventional system centralization methods, people are starting to use decentralized blockchain technology for innovation. The research objective of blockchain 3.0 technology is to support the architecture of the educational digital asset management system also suggested in this article, which also uses bitcoin. Apart from performing essential blockchain validation and storage, it transforms the disparate data that students generate across their classroom and extracurricular learning activities into educational digital assets. To study the growth of school users and achieve educational goals of educating students according to their individual talents and peculiarities, the system can use a variety of heterogeneous data from digital assets.
Abstract Industry and research communities have widely studied Blockchain technology, and the consortium blockchain is currently the most used category with a wide range of applications. However, issues, such as the performance of consensus mechanisms, have become essential constraints on promoting and applying the consortium blockchain. To improve the performance of the consortium blockchain consensus, we use the practical Byzantine fault tolerance (PBFT) consensus widely used in consortium blockchains to reduce the number of consensus nodes to optimize performance. Using the PBFT consensus, we screen high-performance nodes and obtain a reliable and limited number of consensus nodes. We propose a genetic algorithm-based blockchain consensus algorithm improvement scheme, design the fitness function of blockchain nodes and the genetic algorithm to iterate out consensus node groups with excellent indicators continuously, and finally iterate the nodes participating in the consensus. This algorithm can increase the speed and efficiency of the consensus, block generation, and computation. The algorithm in this article is tested on the FISCO BCOS (i.e., a consortium blockchain platform built by the FISCO open-source working group), and controlled experiments and the experimental results illustrate the safety and practicability of the method.
Blockchain consensus algorithms are generally used to ensure data consistency in the blockchain. The current blockchain consensus algorithm has some problems, such as high computing resource consumption, slow block generation speed and difficulty in dealing with malicious node and failure node, which lead to the uncertainty of authenticity of new blocks and trading transaction delay. In view of these problems, we firstly turn the question into solving the problems of electing the one node to keep ledger while ensuring the correctness of ledger information and then synchronize the distributed ledger among most nodes. we propose a consensus algorithm named ENET (Evil Node Elimination Tree) using single chain blockchain structure, with integrating Boyer-Moore majority vote algorithm ensuring the correctness of all new generated blocks. A bottom-up promotion approach to election was adopted to gradually eliminate evil nodes, meanwhile the structure of elimination tree of evil nodes is being constructed. In addition, the distributed synchronization mechanism of top-down update is adopted to recursively update the distributed ledger of all nodes. Theoretical derivation and computer multithreading simulation results show that the communication complexity of this algorithm is at a linear level, and the fault tolerance ratio is 1/4 at the lowest and 3/4 at the highest. The transaction duration is significantly shortened while the double payment problem is eliminated in the system.
This paper covers a novel solution to reduce the gas consumed by Decentralized Applications (DApps) running on Ethereum Virtual Machine (EVM). Smart contracts extend the capabilities of the Blockchain, but the strict gas policy of the EVM limits the implementation of various DApps. On the other hand, Oracle provides a means to use an external execution environment for smart contracts, but its functional limitations and additional costs limit the growth of the DApp market to DApp users. To address the gas consumption crisis of DApps, we designed an event-based resource offloading solution that allows DApp developers to run their own compute servers. By adopting our solution, DApp users only pay the constant and minimized amount of gas fee, while the external server pays highly reduced amount of gas fee instead. We describe the solution in detail with a sample DApp model and mathematically demonstrate the effectiveness of the solution compared to an Oracle-based implementation. Furthermore, we conducted empirical experiment of actual DApp using EVM and verified the reduction of the gas consumption.
Sara Nikolić, Sasa Matic, Darko Čapko, Srđan Vukmirović · 5 authors
Traditional academic certificates have mostly been issued in paper or other physical format and maintained in a registry or a database for a long period of time by a certification authority. The blockchain technology has enabled creation of a decentralized, transaction-based systems, where any transaction ever completed is recorded in a verifiable and permanent way. In this paper, we propose a blockchain-based school management system, named "Ethernal Digital Certificate". Its main purpose is maintaining the data considering summer school events and its participants, as well as issuing certificates for those events. The data is stored on Polygon Supernets blockchain platform. The certificates are issued in the form of NFTs for students who have successfully completed all the courses on an event and they are kept on students' wallets. Once issued, the certificates can't be sold and transferred from one wallet to another. Since the system is based on the blockchain technology and therefore decentralized, there is no need for any third-party organization to verify the certificates.
Despite the success in various scenarios, blockchain systems, especially EVM-compatible ones that serially execute transactions, still face the significant challenge of limited throughput. Concurrent transaction execution is a promising technique to accelerate transaction processing and increase the overall throughput. Existing concurrency control algorithms, however, fail to obtain enough speedups in real-world blockchains due to the high-contention workloads. In this paper, we propose a novel operation-level concurrency control algorithm designed for blockchains. The core idea behind our algorithm is that only operations depending on conflicts should be executed serially, while all other conflict-free operations can be executed concurrently. Therefore, in contrast to the traditional approaches, which block or abort the entire transaction when encountering conflicts, our algorithm introduces a redo phase to resolve conflicts at the operation level by re-executing conflicting operations only. We also develop a set of data dependency tracking mechanisms to achieve precise identification and speedy re-execution for conflicting operations. We implement an open-source prototype based on Go Ethereum and evaluate it using real-world Ethereum blocks. The evaluation results show that our algorithm achieves an average speedup of 4.28$\times$. If combined with state prefetching techniques, our approach can further accelerate the transaction execution by 7.11$\times$.
This paper presents an inter-domain transport net-work slice management with Service Level Agreements (SLA) using the ETSI TeraFlowSDN (TFS) controller. Different instances of the TFS controller are deployed for each involved domain. The communication between the TFS instances is supported by a Distributed Ledger Technology (DLT)-based database. The different TFS instances upload the abstracted view of their topologies and retrieve that from remote peers. When the end- to-end SLA of the transport network slice is violated, the slice is reconfigured avoiding the domain that originated the violation.
With features like immutability and transparency, blockchain and Distributed Ledger Technologies (DLT) can enable the telco industry to exchange services using smart contracts. Consequently, various 6G network stakeholders can participate in a marketplace for inter-provider agreements as either service providers or consumers. As, a blockchain-based 6G network can aid administrative domains in sharing resources (virtual network functions, services, or slices). However, such a dynamic environment requires strict Service Level Agreement (SLA) monitoring and management. Therefore, this paper considers a use case of a smart contract-based inter-provider agreement. We use novel solutions like IOTA Tangle to perform transactions, IPFS to store the hash of use case data files, and chainlink to access off-chain data feeds for SLA monitoring, reducing costs and increasing transparency. We also provide experimental evaluations of and divide the emulation into two phases. Phase 1 consists of choosing the approach and creating a smart contract (SC) (i.e., SC-Marketplace or SC-Auction). Furthermore, phase 2 consists of off-chain data feed to monitor SLA through chainlink. Finally, we measure transaction latency, response time, overall time consumption, and transaction & storage cost. The maximum latency observed in phase 1 is$\approx 25\text{ms}$and$\approx 15\mathrm{s}$for phase 2. Similarly, the average response time for both phases is$\approx 14\mathrm{s}$~ 20s. Lastly, the results also explain that using IOTA-EVM, we can have fee-less transactions, and IPFS helps reduce the storage cost by up to$\approx 80\%$. However, it is concluded that adding chainlink adds additional cost for SLA data feeds.
Dalia Elwi, Osama Abu-Elnasr, A. S. Tolba, Samir Elmougy
Abstract Bitcoin is a digital cryptocurrency which had become the focus of scientific research in the modern era. Blockchain is the underlying technology of Bitcoin because of its decentralization, transparency, trust-less, and immutability features. However, blockchain can be considered the cause of Bitcoin scalability issues especially storage. Nodes in Bitcoin network need to store the full blockchain to validate transactions. By time, the blockchain size will be extremely huge. So, the full nodes will prefer to leave the network, and this leads to the blockchain being centralized and trusted. Therefore, security will be adversely affected. In this paper, we propose a Stateful Layered Chain Model which is based on storing accounts’ balances to reduce the size of the Bitcoin blockchain. This model changes the structure of the traditional blockchain from blocks to layers. The experimental results demonstrated that the proposed model reduces the size of blockchain by about 50.6%. Imlicitly, the transaction throughput can also be nearly doubled.
Damilare Peter Oyinloye, Je Sen Teh, Norziana Jamil, Jiashen Teh
Blockchain is a distributed ledger in which participating users with varying levels of trust agree on the ledger’s content using a consensus mechanism called consensus protocols. There has been a rising interest in the design of consensus protocols since they play a central role in blockchain architecture. However, many recently proposed consensus protocols lack experimental verification which hampers the possible deployment of these protocols in real-world blockchain networks. In this article, we propose a simple tool called simplified consensus protocol simulator (SIM-P) that can accurately simulate the behavior of these consensus protocols with ease. It is an agent-based stochastic simulator that relies on the sequential Monte Carlo method to model how block publishers are selected. The likelihood of each node (represented as agents) being selected as a block publisher is represented by independent trials in a binomial experiment. We provide a base SIM-P model that simulates Proof of Work (PoW) for benchmarking purposes. The PoW model also serves as the basic structure of the simulator that can be adapted to other protocols. We showcase the flexibility of SIM-P by proposing two additional simulation models for Proof of Reputation-X and Proof of Contribution, both of which lack experimental verification in their original design specifications. We show how the simulator can be used to produce vital metrics, such as throughput, resistance against the 51% attack, and energy consumption. We verify the accuracy of SIM-P by comparing PoW’s simulated results with theoretical estimates and historical Bitcoin data.
In this work, we propose a stateless blockchain called CompactChain, which compacts the entire state of the UTXO (Unspent Transaction Output) based blockchain systems into two RSA accumulators. The first accumulator is called Transaction Output (TXO) commitment which represents the TXO set. The second one is called Spent Transaction Output (STXO) commitment which represents the STXO set. In this work, we discuss three algorithms - (i) To update the TXO and STXO commitments by the miner. The miner also provides the proofs for the correctness of the updated commitments; (ii) To prove the transaction's validity by providing a membership witness in TXO commitment and non-membership witness against STXO commitment for a coin being spent by a user; (iii) To update the witness for the coin that is not yet spent; The experimental results evaluate the performance of the CompactChain in terms of time taken by a miner to update the commitments and time taken by a validator to verify the commitments and validate the transactions. We compare the performance of CompactChain with the existing state-of-art works on stateless blockchains. CompactChain shows a reduction in commitments update complexity and transaction witness size which inturn reduces the mempool size and propagation latency without compromising the system throughput (Transactions per second (TPS)).