M D Praveen, Shashikumar G. Totad, Mahadev Rashinkar, Ribhav Ostwal · 6 authors
Blockchain and Distributed Ledger Technology are evolving in today's digital world for faster processing and secure transactions. Most IT industries are migrating their applications to blockchain frameworks because of high security and faster processing operations. Cryptocurrencies and bitcoin applications use Blockchain and distributed ledger technology to perform decentralized transactions. With the current blockchain technology, there is a limitation in storing and processing a large volume of transactions and data, affecting memory and throughput. To overcome this limitation, we propose a methodology to integrate Blockchain with IPFS to enhance the throughput and optimize the memory. As a case study marks card validation application is being developed on the Ethereum framework considering Geth and Parity clients. Blockchain consensus protocol, i.e., proof of work (POW) and proof of stake (POS), are used to build smart contracts and process transactions. InterPlanetary File System (IPFS) is integrated with Blockchain to enhance the throughput and performance of the application. The results indicate that Blockchain integrated with IPFS performs better by optimizing the memory and reducing the transaction delay. The comparative analysis shows that the proposed approach reduces the transaction processing cost by 10% and enhances the throughput by 8% compared to the Fileshare and BlockIPFS techniques.
The Practical Byzantine Fault Tolerant (PBFT) consensus algorithm has many advantages, which makes PBFT utilized widely. Nonetheless, PBFT is not suitable for large-scale node scenarios due to its high communication complexity and it also has an apparent disadvantage of inadequate fault tolerance. The typically derived PBFT algorithms focus on reducing communication complexity at the cost of diminished system security or fault tolerance. In this paper, Dual-Primary-Node derived Practical Byzantine Fault Tolerance (DPNPBFT) is proposed to achieve the best balance of the above three performances. First, DPNPBFT selects dual master nodes based on the idea of power separation. The two master nodes check balance and supervise each other to avoid excessive centralization as a single master node system. It also reduces the communication complexity of the replica node, which only communicates with the master node. Furthermore, we designed the architecture of DPNPBFT to get a practical 49% fault tolerance rate, and it is close to the current mainstream Proof of Work and Proof of Stake algorithms. Experimental results demonstrate that DPNPBFT has O(N) level communication complexity and excellent anti-host node malicious performance. The Transactions Per Second of DPNPBFT is stable at 1700. It proves DPNPBFT has the best performance balance and excellent comprehensive performance for large-scale Internet of Things application scenarios.
Non-Fungible Tokens (NFTs) have lately piqued the interest of investors, with some NFTs achieving selling levels previously inconceivable for a non-fungible virtual asset. This raises intriguing questions about "value" and "scarcity" in relation to blockchain technology, viewed through the lens of a digital asset's non-fungibility, This study seeks to attract attention to these issues inasmuch as they may create a future alternative environment for blockchain development and trading.
Blockchain has become an unavoidable future in enterprise finance, particularly enabling and securing cross-company transactions. By introducing a comparable notion of smart contract, the trusted sub-ledger operation (TSLO), this article will propose a complete architecture based on the Blockchain to solve the traceability and validity of accounting data by assets groupement. TSLO is a more flexible and adaptable method for asset management in the corporate accounting system and the enterprise resource planner. This method is built on a decentralized microservices tree (DMST) and is an extendable E-Binding form of TEA (Triple Entry Accounting). Instead of using a multi-ledger architecture, the Hyperledger Fabric skeleton, limited to participant channels inside one entity or organization, our approach uses decentralized sub-ledgers with an implementation tree (DMST) for an assets-driven transaction. Furthermore, the government’s audit and taxation procedures for financial groups are more accessible by combining Proof of Authority and Proof of Stake to assure the logic of More stake more reputation to preserve.
Piero Fraternali, Sergio Luis Herrera González, Matteo Frigerio, Mattia Righetti
Distributed Ledger Technology (DLT) is one of the most durable results of virtual currencies, which goes beyond the financial sector and impacts business applications in general. Developers can empower their solutions with DLT capabilities to attain such benefits as decentralization, transparency, non-repudiability of actions and security and immutability of data assets, to the price of integrating a distributed ledger framework into their software architecture. Model-Driven Development (MDD) is the discipline that advocates the use of abstract models and of code generation to reduce the application development and integration effort by delegating repetitive coding to an automated model-to-code transformation engine. In this paper, we explore the suitability of MDD to support the development of hybrid applications that integrate centralized database and distributed ledger architectures and describe a prototypical tool capable of generating the implementation artefacts starting from a high-level model of the application and its architecture.
Louis Tremblay Thibault, Tom Sarry, Abdelhakim Hafid
Blockchain systems have seen much growth in recent years due to the immense potential attributed to the technology behind these systems. However, this popularity has outlined a critical scalability issue that most blockchain systems are now confronted with. With their increasing popularity comes an increasing amount of load on the system. Several scaling solutions that modify either the functioning of the underlying protocol or that build on top of them have already been proposed; however, each of these solutions comes with their advantages and disadvantages. This paper aims to survey the current state-of-the-art of rollups as a scaling solution. We discuss the mode of operation of the different types of rollups, outline state-of-the-art implementations of each type together with their features and limitations. We also conduct a performance analysis comparing these implementations. Finally, we outline avenues for future research around rollups as a scaling solution.
Ensuring a production-ready state of the application under development is the imminent feature of the Continuous Delivery (CD) approach. In a blockchain network, nodes communicate and store data in a distributed manner. Each node executes the same business application but operates in a distinct execution environment. The literature lacks research focusing on continuous practices for blockchain and Distributed Ledger Technology (DLT). Specifically, it lacks such works with support for both design and deployment. The author has proposed a solution that takes into account the continuous delivery of a business application to diverse deployment environments in the DLT network. As a result, two continuous delivery pipelines have been implemented using the Jenkins automation server. The first pipeline prepares a business application whereas the second one generates complete node deployment packages. As a result, the framework ensures the deployment package in the actual version of the business application with the node-specific up-to-date version of deployment configuration files. The Smart Contract Design Pattern has been used when building a business application. The modeling aspect of blockchain network installation has required using Unified Modeling Language (UML) and the UML Profile for Distributed Ledger Deployment. The refined model-to-code transformation generates deployment configurations for nodes. Both the business application and deployment configurations are stored in the GitHub repositories. For the sake of verification, tests have been conducted for the electricity consumption and supply management system designed for prosumers of renewable energy.
Sura I. Mohammed Ali, Haitham Farouk, Hussien Sharaf
Blockchain stores a series of transactions in form of a sequence of linked blocks. Hence, the concept of a single decentralized ledger is easily maintained. Transactions and interactions that take place among the participants accessing the distributed and decentralized but cooperative blockchain network are held through a single ledger. A student information system (SIS) can make use of a decentralized, reliable, and highly trusted ledger that stores vital information. Traditional education systems encounter problems such as centralized record keeping where fault tolerance depends on a single cloud provider; not to mention locally hosted databases. The implementation of blockchain in the education sector provides a new horizon for set of non-functional requirements including but not limited to: security, immutability, independence from the institution, immutability of official records and certificates. In addition, total trust in the accuracy and infallibility are all gathered in the decentralized ledgers of blockchain. The proposed models emphasize on the data availability; represented in students' ability to access all of their data at any time. This paper proposes three models for using blockchains to implement fully functional SIS that maintains transactions such as students’ and faculty members’ records, course registration records and student marks. In addition, avoiding the role of a super administrator or a centralized exposed store where data integrity is vulnerable. Using the proposed models pushes towards an electronic community where genuine certificates can be easily issued and published to the interested parties without the need for involving a centralized administration.
Many cross-organization cooperation applications of blockchain-based distributed ledger technologies (DLT) do not aim at innovation at the cooperation pattern level: essentially the same ''business'' is conducted by the parties, but this time without a central party to be trusted with bookkeeping. The migration to DLT is expected to have a negative performance impact, but some DLTs, such as Hyperledger Fabric, are accepted to be much better suited performance-wise to such use cases than others. However, with the somewhat surprising, but ongoing absence of application-level performance benchmarks for DLTs, cross-DLT comparison for "classic" workloads and the evaluation of the performance impact of "blockchainification" is still ill-supported. We present the design and Hyperledger Caliper-based open implementation of a full port of the classic TPC-C benchmark to Hyperledger Fabric, complete with a structured approach for transforming the original database schema to a smart contract data model. Initial measurements about the workload characteristics that will affect the design of large-scale performance evaluations are also included.
The distributed transmission of a dynamic blockchain in a cloud computing platform may cause network overload. To overcome this challenge, a novel idea for a network architecture that is suitable for blockchain transmission and storage is proposed. Emerging edge computing technology has been proven to improve the efficiency of blockchain construction and operation. In this paper, we focus on solving the problem of unbalanced resource allocation for blockchain construction and transmission in a novel edge computing network architecture. We propose the edge bandwidth and storage optimization (EBSO) algorithm to balance effective bandwidth allocation and storage space selection during dynamic blockchain processing. In addition, we build a dynamic blockchain based on a link bandwidth allocation analysis in an edge computing network environment. Subsequently, the reasonable value range of the tradeoff parameter γ between the link bandwidth and storage space during the transmission of the constructed dynamic blockchain is determined. Finally, we use version 2 of the network simulator (ns-2) to simulate the performance of the EBSO algorithm and compare it with other excellent algorithms in terms of transmission bandwidth efficiency (TBE), storage space efficiency (SSE), blockchain construction efficiency (BCE), average throughput, and average delay in the same network environment.
Ensuring a production-ready state of the application under development is the immanent feature of the continuous delivery approach. In a blockchain network, nodes communicate, storing data in a decentralized manner. Each node executes the same business application but operates in a distinct execution environment. The literature lacks research, focusing on continuous practices for blockchain and distributed ledger technology. In particular, such works with support for both software development disciplines of design and deployment. Artifacts from considered disciplines have been placed in the 1 + 5 architectural views model. The approach aims to ensure the continuous deployment of containerized blockchain distributed applications. The solution has been divided into two independent components: Delivery and deployment. They interact through Git distributed version control. Dedicated GitHub repositories should store the business application and deployment configurations for nodes. The delivery component has to ensure the deployment package in the actual version of the business application with the node-specific up-to-date version of deployment configuration files. The deployment component is responsible for providing running distributed applications in containers for all blockchain nodes. The approach uses Jenkins and Kubernetes frameworks. For the sake of verification, preliminary tests have been conducted for the Electricity Consumption and Supply Management blockchain-based system for prosumers of renewable energy.
Abdullah Ayub Khan, Zaffar Ahmed Shaikh, Лаура Байтенова, Lyailya Mutaliyeva · 9 authors
Quality-of-service (QoS) is the term used to evaluate the overall performance of a service. In healthcare applications, efficient computation of QoS is one of the mandatory requirements during the processing of medical records through smart measurement methods. Medical services often involve the transmission of demanding information. Thus, there are stringent requirements for secure, intelligent, public-network quality-of-service. This paper contributes to three different aspects. First, we propose a novel metaheuristic approach for medical cost-efficient task schedules, where an intelligent scheduler manages the tasks, such as the rate of service schedule, and lists items utilized by users during the data processing and computation through the fog node. Second, the QoS efficient-computation algorithm, which effectively monitors performance according to the indicator (parameter) with the analysis mechanism of quality-of-experience (QoE), has been developed. Third, a framework of blockchain-distributed technology-enabled QoS (QoS-ledger) computation in healthcare applications is proposed in a permissionless public peer-to-peer (P2P) network, which stores medical processed information in a distributed ledger. We have designed and deployed smart contracts for secure medical-data transmission and processing in serverless peering networks and handled overall node-protected interactions and preserved logs in a blockchain distributed ledger. The simulation result shows that QoS is computed on the blockchain public network with transmission power = average of −10 to −17 dBm, jitter = 34 ms, delay = average of 87 to 95 ms, throughput = 185 bytes, duty cycle = 8%, route of delivery and response back variable. Thus, the proposed QoS-ledger is a potential candidate for the computation of quality-of-service that is not limited to e-healthcare distributed applications.
Runkai Yang, Xiaolin Chang, Jelena Mišić, Vojislav B. Mišić
Bitcoin and Ethereum are the top two blockchain-based cryptocurrencies whether from cryptocurrency market cap or popularity. However, they are vulnerable to selfish mining and stubborn mining due to that both of them adopt Proof-of-Work consensus mechanism. In this paper, we develop a novel Markov model, which can study selfish mining and seven kinds of stubborn mining in both Bitcoin and Ethereum. The formulas are derived to calculate several key metrics, including relative revenue of miners, blockchain performance in terms of stale block ratio and transactions per second, and blockchain security in terms of resistance against double-spending attacks. Numerical analysis is conducted to investigate the quantitative relationship between the relative-revenue-optimal mining strategy for malicious miners and two miner features in Bitcoin and Ethereum, respectively. The quantitative analysis results can assist honest miners in detecting whether there is any malicious miner in the system and setting the threshold of mining node's hash power in order to prevent malicious miners from making profit through selfish and stubborn mining.
The current micro-teaching process is readily online, and it is functional anywhere and anytime ubiquitously. All or most teaching and learning activities are accessible in centralized storage. However, centralized storage has inherent problems, such as a single point of failure with many possible data breaches, much duplication of data stored repeatedly in one location, and the lack of trust in third parties for data stored in centralized storage. Further issues include the high cost and low performance of the online systems that hinder the quality of the education process. In this paper, we propose a new framework Education Exchange Storage Protocol (EESP). EESP aims to improve the efficiency of the decentralized storage ecosystem in micro-teaching, coupled with blockchain technology acting as a control layer. Blockchain empowers the decentralized system by bringing together the most incompatible unstructured entities and integrate them. The decentralized storage system is armed with a blockchain smart contract that acts as a control layer, featuring impregnable security, immutability, trace-ability, and transparency. The EESP framework aims to elevate teaching and learning through blockchain decentralized storage systems in a transformational way, including but not limited to things like micro-credential, massive open online courses, and gamification, all in a single immersive learning platform. Finally, we tested and evaluated this framework using the truffle simulator, and the results demonstrate that the EESP model significantly improves performance.
The Ethereum ecosystem was maintained by a distributed global network of computers that required massive amounts of computational power. Previous work on estimating the energy use and emissions of the Ethereum network has relied on top-down economic analysis and rough estimates of hardware efficiency and emissions factors. In this work we provide a bottom-up analysis that works from hashrate to an energy usage estimate, and from mining locations to an emissions factor estimate, and combines these for an overall emissions estimate. We analyze the entire history of PoW Ethereum, from creation to the merge.
N. Sánchez-Gómez, Jesús Torres Valderrama, M. Mejías, Alejandra Garrido
One of the key benefits of blockchain technology is its ability to keep a permanent, unalterable record of transactions. In business environments, where companies interact with each other without a centralized authority to ensure trust between them, this has led to blockchain platforms and smart contracts being proposed as a means of implementing trustworthy collaborative processes. Software engineers must deal with them to ensure the quality of smart contracts in all phases of the smart contract lifecycle, from requirements specifications to design and deployment. This broad scope and criticality of smart contracts in business environments means that they have to be expressed in a language that is intuitive, easy-to-use, independent of the blockchain platform employed, and oriented towards software quality assurance. In this paper we present a key component: a first outline of a UML-based smart contract meta-model that would allow us to achieve these objectives. This meta-model will be enriched in future work to represent blockchain environments and automated testing.
Aleksandr Zavodovski, Lorenzo Corneo, Andreas Johnsson, Nitinder Mohan · 8 authors
Edge computing promises to bring computation close to the end-users to support emergent applications such as virtual reality. However, the computational capacity at the edge of the network is currently limited. To become a pervasive paradigm, edge computing needs highly dispersed decentralized deployments, that, contrary to cloud, cannot benefit from economies of scale. In this situation, crowdsourcing appears attractive - there are plenty of computing devices at the disposal of the general public, and these devices are located exactly where computing power is needed the most - at the edge of the network. Crowdsourcing has been a success maker for scientific computing projects, e.g., [email protected], or distributed ledger systems empowering decentralized finance. However, as of now, there is no crowdsourced system that addresses the needs of edge computing. In this position paper, we aim to identify the causes of this shortcoming, analyze the potential ways to overcome it, and outline future directions.
Befekadu G. Gebraselase, Bjarne E. Helvik, Yuming Jiang
Blockchain is a technology that provides a distributed ledger that stores previous records while maintaining consistency and security. Bitcoin is the first and largest decentralized electronic cryptographic system that uses blockchain technology. It faces a challenge in making all the nodes synchronize and have the same overall view with the cost of scalability and performance. In addition, with miners' financial interest playing a significant role in choosing transactions from the backlog, small fee or small fee per byte value transactions will exhibit more delays. To study the issues related to the system's performance, we developed an $M(t)/M^N/1$ model. The backlog's arrival follows an inhomogeneous Poison process to the system that has infinite buffer capacity, and the service time is distributed exponentially, which removes $N$ transactions at time. Besides validating the model with measurement data, we have used the model to study the reward distribution when miners take transaction selection strategies like fee per byte, fee-based, and FIFO. The analysis shows that smaller fee transactions exhibit higher waiting times, even with increasing the block size. Moreover, the miner transaction selection strategy impacts the final gain.
Blockchain technology has been recognized as a promising solution to enhance the security and privacy of Internet of Things (IoT) and Edge Computing scenarios. Taking advantage of the Proof-of-Work (PoW) consensus protocol, which solves a computation intensive hashing puzzle, Blockchain assures the security of the system by establishing a digital ledger. However, the computation intensive PoW favors members possessing more computing power. In the IoT paradigm, fairness in the highly heterogeneous network edge environments must consider devices with various constraints on computation power. Inspired by the advanced features of Digital Twins (DT), an emerging concept that mirrors the lifespan and operational characteristics of physical objects, we propose a novel Miner-Twins (MinT) architecture to enable a fair PoW consensus mechanism for blockchains in IoT environments. MinT adopts an edge-fog-cloud hierarchy. All physical miners of the blockchain are deployed as microservices on distributed edge devices, while fog/cloud servers maintain digital twins that periodically update miners’ running status. By timely monitoring miner’s footage that is mirrored by twins, a lightweight Singular Spectrum Analysis (SSA) based detection achieves to identify individual misbehaved miners that violate fair mining. Moreover, we also design a novel Proof-of-Behavior (PoB) consensus algorithm to detect byzantine miners that collude to compromise a fair mining network. A preliminary study is conducted on a proof-of-concept prototype implementation, and experimental evaluation shows the feasibility and effectiveness of proposed MinT scheme under a distributed byzantine network environment.
Ethereum, that enable development of decentralized applications, will likely to leverage cloud computing. In this research, we evaluate the performance of a cloud-based Ethereum network. We researched 3 Ethereum networks, namely: Ethereum mainnet, Ethereum testnet Ropsten, and Ethereum testnet Rinkeby. We analyze the computational resource utilization required to run an Ethereum node for a month as well as the costs involved. Research shows that the utilization of computing resources on the Main Net is generally higher than on the Test Net network. Computing resources used in the cloud cost thousands of dollars and this will increase as the number of nodes running to support the Ethereum network.
With the development of blockchain and digital currencies, central banks all over the world are accelerating the process of CBDC development. However, it is still controversial on adoption of blockchain in CBDC design. In the paper, we analyze both functional and non-functional requirements of CBDC design, and make a literature review on blockchain based CBDC schemes. Analysis findings show that permissioned blockchain is more suitable for CBDC than permissionless blockchain. Besides, there are some challenges in blockchain based CBDC, such as performance, scalability, and cross-chain interoperability. Our analysis is timely and can provide guidelines for blockchain based CBDC design.
Network Function Virtualization (NFV) is considered to be a hopeful technology for supporting blockchain with many features like flexible networks and intelligent equipment. NFV decreases the expenses incurred on the maintenance and operation of assets that are generated through expenses, in addition to capital expenditures based on the isolate the physical devices from the main tasks executed by that equipment. Blockchain currency transfers or technology is the most powerful security tool that ensures the security of data. The prominent challenges in NFV are the processes of transition, vendor compatibility, network management, rapid growth, and security. The software industry and skills of networking are experiencing fast expansion and deployment of the Network Functions Virtualization (NFV) approach, jointly in blockchain and cloud networks. In this paper, a novel method is offered to virtualize the work of the blockchain based on the NFV with auto work of the smart contract between virtual nodes based on cloud computing. By blending NFV with Blockchain, all of the above-mentioned challenges have been overcome by moving to software environments through creating virtual nodes, as well as smooth interaction among them and managing the transactions between nodes and clients, indicating ideal network management. Through the proposed work, a throughput of up to 20% is obtained by applying NFV compared to not applying NFV to the blockchain. In addition, the costs of the hardware are eliminated and eventually a secure environment is used which distances the system from virtual attacks.
Recent years have witnessed the advancement of the Internet of Things (IoT) and its emergence as a technology that could revolutionize many businesses. It helps considerably in creating data-driven business models with the insights it provides. IoT systems are deployed in data collection, monitor processes, provide insights and allow businesses to make data-driven productivity improvements. However, IoT systems are often experiencing data loss due to inevitable failures ranging from devices, networks, to the application layer, especially in scarce infrastructure resources environments. Data loss might be unrecoverable in many circumstances. As such, this research presents a blockchain based IoT model (framework) with the aim of circumventing data loss. We envisioned IoT blockchain technology in enhancing data veracity with data loss tolerance. That is, to have blockchain enhancing the IoT data veracity by leveraging on the features existed in its peer-to-peer network (P2P) and distributed ledger storage technology (DLT). Additionally, the edge computing of IoT blockchain technology is also conceptually workable; with intelligent small computing resources, it opens up a new era of bringing the intelligence of data collection, connectivity, computation and storage into the edge/device layer. A novel IoT blockchain strength monitoring system is also been studied to further enhance data veracity; this is achieved through a capacitance monitoring on the IoT blockchain system. The empirical results show that the proposed IoT blockchain with a strength monitoring model can alleviate data loss and thus enhance data veracity with data loss tolerance.