Blockchain technology has wide applications in the fields of finance, public welfare, and the Internet of Things. Owing to a blockchain's characteristics, which include decentralization, openness, autonomy, immutability, and anonymity, it is difficult to quickly reach a reliable consensus result among its nodes. This work proposes a performance-optimized consensus mechanism based on node classification. Nodes are classified into accounting, validating, and propagating ones based on their trust values. All accounting nodes form an accounting node group, from which one is selected as the current accounting node to package transactions into a block, and the remaining nodes in the accounting node group can be used to validate the block quickly, owing to their high trust values. Validating and propagating nodes are responsible for validating and propagating transactions, respectively. All nodes' trust values are dynamically updated according to their behavior and performance. Corresponding algorithms are designed to realize the proposed consensus mechanism. The experimental results show that the proposed consensus mechanism provides higher throughput, lower consumption, and higher fault tolerance than some popularly used methods, thereby advancing the field of consortium blockchains.
Mahdi Fahmideh, John Grundy, Aakash Ahmad, Jun Shen · 11 authors
Many scientific and practical areas have shown increasing interest in reaping the benefits of blockchain technology to empower software systems. However, the unique characteristics and requirements associated with Blockchain-based Software (BBS) systems raise new challenges across the development lifecycle that entail an extensive improvement of conventional software engineering. This article presents a systematic literature review of the state-of-the-art in BBS engineering research from the perspective of the software engineering discipline. We characterize BBS engineering based on the key aspects of theoretical foundations, processes, models , and roles . Based on these aspects, we present a rich repertoire of development tasks, design principles, models, roles, challenges, and resolution techniques. The focus and depth of this survey not only give software engineering practitioners and researchers a consolidated body of knowledge about current BBS development but also underpin a starting point for further research in this field.
Smart contract execution engines are a central part of transaction processing in blockchains. One of the most widely used execution engines is the Ethereum Virtual Machine (EVM). EVM performance is a key determinant of the overall blockchain system. Being able to gather detailed insights into EVM performance characteristics is essential not only when implementing EVMs, but also when designing and dimensioning blockchain-based information systems. Today, there is no precise and easy-to-use solution to gather such information. To address this issue, we introduce EVM-Perf, a high-precision EVM evaluation, and analysis framework. Our framework allows detailed performance analysis of arbitrary EVM implementations. Unlike previous work, it leverages statical analysis methods to achieve higher levels of accuracy. We provide an open-source implementation of EVM-Perf and use it to conduct extensive performance analysis for different physical machines. It comprises both machines with x86_64 as well as ARMv8 instruction set architecture. We discuss how EVM-Perf supports system architects with machine selection as well as configurations of Ethereum deployments, e.g., determining Gas limits or block intervals.
Remigijus Paulavičius, Saulius Grigaitis, Ernestas Filatovas
Since the introduction of Bitcoin, blockchain has attracted tremendous interest from both academia and industry. During the last decade, various large-scale blockchain systems were developed. However, the complexity of large-scale distributed systems makes the performance evaluation process challenging and costly. Here, blockchain simulators give the possibility to repeat complex real-world processes at a low cost. Simulators are easily extensible and can test distributed ledger performance using different settings and parameter variations. This work reviews and summarizes the current status of the state-of-the-art blockchain simulators.
Binh Minh Nguyen, Thang Nguyen, Thieu Nguyen, Ba-Lam Do
Over the last years, many blockchain platforms opt for Delegated Proof-of-Stake (DPoS) consensus protocol for their network deployment. However, using the DPoS, nodes on the network tend to vote for the nodes that are more likely to become block producers after several voting rounds. Hence, with DPoS, the number of block producers is quite small compared to the total number of nodes in the blockchain network. Besides, with DPoS consensus, the distribution of block producers often centralizes into several individual nodes. This paper proposes a novel consensus protocol called Meta-heuristic Proof of Criteria (MPoC) to overcome the disadvantages. Our protocol enables multiple operational criteria to evaluate all blockchain nodes during the block producer selection process. We apply meta-heuristic algorithms to optimize the decentralized level of the node selection based on the set of criteria weights to increase the democracy of the blockchain network.We carry out experiments to evaluate the block producer decentralization of MPoC as compared with DPoS. The achieved results show that our consensus protocol improves the decentralization of block producers as expected. We also show the feasibility of applying different meta-heuristic algorithms to our consensus protocol of blockchain through experiments.
Proof of Staked Hardware Consensus (PoSH) Consensus was designed to achieve Nakamoto-style probabilistic consensus on the contents of a cryptocurrency ledger in a permissionless decentralized network while serving as the foundation of an openly mintable cryptocurrency without winner-takes-all lottery-style block rewards. This demo paper presents a proof of concept implementation of a PoSH consensus blockchain and the technical solutions the implementation introduces to realize PoSH in practice.
Cyril Naves Samuel, Severine Glock, François Verdier, Patricia Guitton-Ouhamou
Enterprises are realizing their distributed ledger use-cases with private blockchains as it is more secure, efficient, and reliable compared to the public networks. Due to this reason we evaluate the behavior and performance of Ethereum clients namely Geth, OpenEthereum (Parity), and Hyperledger Besu along with their Proof of Authority consensus algorithms from an enterprise perspective. We propose a testing methodology adapted to Microsoft Azure Cloud infrastructure overcoming the drawbacks of existing works. We analyze the behavior in each of the clients from different Ethereum focused parameters. We propose a novel load-balancer middleware specific to Ethereum and integrate in our test tool for uniform and reliable distribution of transactions. We analyze the bottlenecks and their root causes in each of the clients and report it to the community.
May 1, 2021·2021 7th IEEE Intl Conference on Big Data Security on Cloud (BigDataSecurity), IEEE Intl Conference on High Performance and Smart Computing, (HPSC) and IEEE Intl Conference on Intelligent Data and Security (IDS)
Contemporarily, DPoS is the fastest, most effective, decentralized and flexible consensus mechanism among all consensus mechanisms. Similar to the vote of the board, the holders cast a certain number of delegates to perform verification and accounting on their behalf in DPoS. In order to select the most appropriate delegates to implement the operations in blockchain, the DPoS consensus mechanism needs to be improved. Therefore, an improved DPoS consensus mechanism based on Probabilistic Linguistic Term Set (PLTS) is proposed in this paper. Just like human elections, this method allows each node to vote “support” and “oppose” for the delegate node. The efficient and flexible method reduces the probability of malicious nodes becoming delegates and guarantees the security of block generation in the blockchain. The effectiveness of the improved DPoS was verified by examples.
With the continuous development and innovation of blockchain technology, a large number of blockchain networks with different characteristics and adapting to the needs of different scenarios have emerged in the fields of payment settlement, product traceability, identity authentication and so on, forming many islands of value. Blockchain cross-chain technology is an important technical means to realize inter-chain interconnection and value transfer. This paper systematically summarizes the current blockchain mainstream cross-chain technology. Firstly, this paper summarizes the basic knowledge of cross-chain technology, and then introduces the mainstream cross-chain techniques. Finally, this paper analyzes the challenges of cross-chain technology and forecasts its future prospect.
Andrzej Wilczyński, Joanna Kołodziej, Daniel Grzonka
The intensive development and growth in the popularity of mobile cloud computing services bring a critical need to introduce new solutions that increase the level of cloud and users security. One of the critical issues in highly distributed computational systems is a task scheduling process. This process may be exposed to many external and internal security threats, like task injection, machine failure or generation of incorrect schedule. These problems are especially important in mobile environments. It can be even more complicated if we take into consideration the personalization of the services offered. Recently, blockchain has been gaining rapidly in popularity, combining high efficiency with applications in distributed and highly personalized computational environments. In this paper, we developed and described a novel model for security-aware task scheduling in cloud computing based on blockchain technology. Unlike other blockchain-based solutions, the proposed model uses Proof of Stake, which does not have high requirements for computing power. A series of conducted experiments confirmed the high efficiency of the proposed model.
Anne Sofie Vingerhoets, Samedi Heng, Yves Wautelet
New blockchain-based projects do appear every day. The technology has indeed been popularized by cryptocurrencies but is now gaining interest in various domains and new types of applications are evaluated constantly. Understanding the impact of blockchain adoption on the organization and the internals of blockchain-related behavior nevertheless remains a challenge for managers but also for IT professionals. This article studies how two existing organizational and software modeling languages can be fit to document a blockchain development project in Supply Chain Management (SCM) at its earliest stages. These two frameworks are i* on the one side and the Unified Modeling Language (UML) use case and sequence diagrams on the other side. The real life project used as a case study in this application is ‘Farm-to-Fork’ where a blockchain solution for the Supply Chain (SC) of farm animals is developed. The application of the frameworks is intended to identify their strengths and weaknesses. An extension of i* is proposed to deal with blockchain privacy issues as well as laws and norms. We finally point to the complementarity of i* and UML use case and sequence diagrams in a Blockchain-Oriented Software Engineering (BOSE) context. The i* framework indeed supports early requirements to understand the impact of the project on stakeholders while UML use case and sequence diagrams support the late requirements and the design by depicting the use of blockchain and some of its behavioral mechanisms.
The act of maintaining educational records both online and on paper have become a norm. With the enforcement of lockdowns due to the Covid-19 pandemic, the education sector attempted to move their entire operations online. However with this move, various operations such as Verification of Documents, Approval of LORs have become harder to deal with in a legitimate manner. In this paper, we have compared various existing methods to deal with the problem at hand and proposed our system for the same.
Jae-Yun Kim, Jun-Mo Lee, Yeon-Jae Koo, Sang-Hyeon Park · 5 authors
Ethereum is a popular account-based blockchain whose number of accounts and transactions has skyrocketed, causing its data explosion. As a result, ordinary clients using PCs or smartphones cannot easily bootstrap as a full node, but rely on other full nodes to verify transactions, thus being exposed to security risks. The most serious overhead is caused by synchronizing the state of all accounts in the block's state trie, which takes several tens of gigabytes. Observing that more than 95% of the accounts are dormant, we propose a novel state optimization technique, named Ethanos. Ethanos downsizes the state trie by periodically emptying it, and then re-build it only with the active accounts used in the period's transactions. Ethanos runs transactions using the accounts available in the current period's state trie as well as those available at the end of the previous period's state trie. For an account in neither of the tries, the account first restores itself by transmitting a restore transaction. One important result of this state management is that a node can now bootstrap only with the latest period's state trie, yet can fully verify all transactions thereafter. We evaluated Ethanos with real Ethereum transactions for 300,000 blocks from the 7.0 million block, with a one-week period of emptying the state trie. Our result shows that Ethanos can sharply reduce the state trie, with only a tiny fraction of the restore transactions. More importantly, unlike the Ethereum state trie which continues to grow as time goes on, the Ethanos state trie size at the end of each period is bounded by a few hundred MB, when there are more than one million, one-week-active accounts.
B. Prabadevi, N. Deepa, Quoc‐Viet Pham, Dinh C. Nguyen · 8 authors
Blockchain is gaining momentum as a promising technology for many application domains, one of them being the Edge-of- Things (EoT) that is enabled by the integration of edge computing and the Internet-of-Things (IoT). Particularly, the amalgamation of blockchain and EoT leads to a new paradigm, called blockchain enabled EoT (BEoT) that is crucial for enabling future low-latency and high-security services and applications. This article envisions a novel BEoT architecture for supporting industrial applications under the management of blockchain at the network edge in a wide range of IoT use cases such as smart home, smart healthcare, smart grid, and smart transportation. The potentials of BEoT in providing security services are also explored, including access authentication, data privacy preservation, attack detection, and trust management. Finally, we point out some key research challenges and future directions in this emerging area.
Bishakh Chandra Ghosh, Tanay Bhartia, Sourav Kanti Addya, Sandip Chakraborty
With the increasing adoption of private blockchain platforms, consortia operating in various sectors such as trade, finance, logistics, etc., are becoming common. Despite having the benefits of a completely decentralized architecture which supports transparency and distributed control, existing private blockchains limit the data, assets, and processes within its closed boundary, which restricts secure and verifiable service provisioning to the end-consumers. Thus, platforms such as e-commerce with multiple sellers or cloud federation with a collection of cloud service providers cannot be decentralized with the existing blockchain platforms. This paper proposes a decentralized gateway architecture interfacing private blockchain with end-users by leveraging the unique combination of public and private blockchain platforms through interoperation. Through the use case of decentralized cloud federations, we have demonstrated the viability of the solution. Our testbed implementation with Ethereum and Hyperledger Fabric, with three service providers, shows that such consortium can operate within an acceptable response latency while scaling up to 64 parallel requests per second for cloud infrastructure provisioning. Further analysis over the Mininet emulation platform indicates that the platform can scale well with minimal impact over the latency as the number of participating service providers increases.
The increasing adoption of multi-cloud computing has created new opportunities for improving resource utilization, service reliability, and reducing dependence on a single cloud provider. However, the distributed nature of multi-cloud infrastructures introduces significant challenges in maintaining data security, privacy, and continuous service availability. This study presents a dynamic security framework designed for multi-cloud environments that integrates adaptive monitoring with a multi-layer encryption mechanism. The proposed approach intelligently selects suitable encryption techniques based on data sensitivity, file size, and available computing resources to achieve an optimal balance between security and performance. The framework Dynamic Resource Management Algorithm(DRMA) for secure key establishment, efficient symmetric encryption for protecting data, and zero-knowledge proof-based authentication to ensure secure user verification without revealing sensitive information. A comprehensive performance evaluation was conducted by comparing the proposed model with conventional RSA-based security approaches. Experimental results demonstrate improved computational efficiency, reduced encryption overhead, enhanced scalability, and stronger protection against unauthorized access. Furthermore, the framework provides resilience against both conventional cyberattacks and emerging quantum computing threats while maintaining efficient resource utilization. These findings indicate that the proposed solution offers a practical and secure approach for protecting data and improving the reliability of modern multi-cloud environments.
Blockchain is an emerging technology for decentralized transactional data sharing networks of untrusted participants. Monitoring and alerting are crucial functionalities when it comes to blockchain projects running in production. In the meantime, different blockchain monitoring systems lack detailed and real-time metrics. In addition to that, the adoption of different DLTs (Distributed Ledger Technologies) is poor. To solve this problem, we propose a realtime-based information framework to monitor blockchain applications. Our monitoring framework is not only a log-based method but also gathers other system metrics (e.g., CPU throughput, latency). The main benefits of our approach are lower configuration setup, more detailed metrics, and, larger DLTs adoption than the existing monitoring tools. We implement the framework to monitor three well-known blockchain systems. The experimental results show that our framework can make a detailed and realtime monitoring of blockchain projects.
Ethereum is a promising but revolutionary blockchain approach to support rich computational services enabled by Turing-complete instructions, also known as smart contract. Using smart contract as "back-end", any party can publish its Decentralized Applications (DApps) available to all Internet users. In other words, blockchain and smart contract enable evolving existing Internet services and applications to decentralised versions. With the developments of versatile Internet applications, the QoS requirements can be very different. For example, new-age applications such as AR/VR can be quite sensitive to even millisecond delays. End-to-end transaction latency in blockchain is a critical factor that affects the performance of DApps. It is the time duration from sending out a transaction (from the client) to having the transaction recorded on the chain. In this paper, we experimentally evaluate the end-to-end latency in Ethereum and discuss the factors that may affect latency on the Ethereum main-net. It has a particular focus on the gas price because it is a key parameter controlled by users. The experiment results demonstrate some counter intuitive finding, e.g. increasing gas price does not reduce the Ethereum end-to-end latency significantly for a certain range of gas prices.
Blockchain technology is the need of an hour for ensuring security and data privacy. However, very limited tools and documentation are available, therefore, the traditional code-centric implementation of Blockchain is challenging for programmers and developers due to inherent complexities. To overcome these challenges, in this article, a novel and efficient framework is proposed that is based on the Model-Driven Architecture. Particularly, a Meta-model (M2 level Ecore Model) is defined that contains the concepts of Blockchain technology. As a part of tool support, a tree editor (developed using Eclipse Modeling Framework) and a Sirius based graphical modeling tool with a drag-drop palette have been provided to allow modeling and visualization of simple and complex Blockchain-based scenarios for security labs in a very user-friendly manner. A Model to Text (M2T) transformation code has also been written using Acceleo language that transforms the modeled scenarios into java code for Blockchain application in the security lab. The validity of the proposed framework has been demonstrated via a case study. The results prove that our framework can be reliably used and further extended for automation and development of Blockchain-based application for security labs with simplicity.
Large-scale development and maintenance projects involve numerous dependencies across multiple disparate organizations, and these projects are subject to contractual stipulations, customer requirements, stakeholder expectations, and compliance/regulatory issues. Because these dependencies and constraints can change over time, mechanisms must exist to absorb, propagate, and implement perturbations to the original scope of work. Such mechanisms are generally human-oriented, involving significant effort to confirm successful modification while avoiding systemic regression. Distributed Ledger Technology alleviates concerns of regression while providing costeffective, actionable business insight during the development of large-scale, integrated systems. Fine-grained insights benefit all parties involved in the system's development, allowing for the incorporation of necessary systemic changes in an economical and informed manner. The system described in this work provides users of varying business roles with a single, clear, and concise view of their collaborative, large-scale development projects. This approach provides needed flexibility and functionality, allowing its users to maintain rigorous traceability while minimizing the time and attention needed to maintain valid project records. Further, practitioners are more well-informed regarding change impact and need not rely solely on subject-matter experts' insights and judgments; instead, they rely on artifact provenance to reliably view the past and present of the project and reliably predict future impacts. Combining distributed ledgers and distributed storage creates a scalable, flexible platform for enterprise-grade project management.
Blockchain is a distributed database shared among disparate parties. It promises to enable new applications and solutions to wide-ranging domains. However, today's blockchains suffer from low throughput and high latency. This impedes widespread adoption of more complex blockchain-based applications. We propose a new direction for the future development of blockchains: pushing utmost work to client-side to make the blockchain-core as simple as possible. To show the feasibility and practicability of this idea, we construct both client-assisted consensus and client-assisted smart contracts. The client-assisted consensus only requires a single round-trip between clients and blockchain nodes; it is leaderless and parallelizable. Our experimental results show that it can process thousands of transactions per second when the number of replicas is 400. The client-assisted smart contract pushes the expensive execution to client-side and ensures the correctness by verifiable computation. It avoids duplicated execution, allows parallel execution and reduces transaction/blockchain sizes.
Simonetta Balsamo, Andrea Marin, Isi Mitrani, Nicola Rebagliati
In the last years, blockchains have become a popular technology to store immutable data validated in a peer-to-peer way. Software systems can take advantage of blockchains to publicly store data (organised in transactions) which is immutable by design. The most important consensus algorithm in public blockchains is the proof-of-work in which miners invest a huge computational power to consolidate new data in a ledger. Miners receive incentives for their work, i.e., a fee decided and paid for each transaction. Rational miners aim to maximise the profit generated by the mining activity, and thus choose the transactions offering the highest fee per byte for their consolidation. In this paper, we propose a queueing model to study the relation between the fee offered by a transaction and its expected consolidation time, i.e., the time required to be added to the blockchain by the miners. The solution of the queueing model, although approximate, is computationally and numerically efficient and software systems can use it online to analyse the trade-off between costs and response times. Indeed, a static configuration of the model would not account for the high variations in the blockchain workload and fees offered by other users.
Because of the anti-tampering, decentralization, anonymous transaction, and other characteristics of the blockchain, it is considered to be a technology that can bring huge changes to the Internet field, especially the financial Internet. As a huge distributed ledger, the blockchain has obvious deficiencies in query processing module design and client query performance. In addition, the current blockchain storage engine cannot provide version control and multi-person collaboration functions. This article proposes to solve the problem of query performance and query semantics not rich by linking other databases, the version control function is realized by separately designing the version control semantics, and the function of deleting the duplicate data by the Pos-tree can be effectively used to solve the problem of waste of storage space during version control. Experiments show that under normal network delay $(\lt 80$ ms), the middleware system proposed in this paper has a slight improvement in query performance, and can also save storage space as much as possible during version control.
Sarah Iqbal, Rafidah Md Noor, Asad Waqar Malik, Anis Ur Rahman
The industrial Internet of Things (IIoT) has emerged as an essential paradigm to enhance industrial operations and productivity through efficient utilization of available resources. The paradigm allows industrial devices to share computing resources based on locality constraints to support innovative services. In this article, we propose a trusted multihop collaborative computing model for the efficient utilization of nearby devices in an IIoT environment. To establish trust, we explore a social-aware incentive scheme managed by network edge, using distributed ledgers. The extensive simulation results demonstrate the effectiveness of the proposed model in the presence of malicious nodes in the industrial environment.