The evolution of the Industrial Internet of Things (IIoTs) greatly increases the volume of data generated by the connected IIoT devices. IIoT data are playing an increasingly important role in various industrial sectors. IIoT data sharing helps enterprises make better production decisions and respond to market changes timely. However, the distrust among IIoT entities and IIoT entities’ distrust of data-sharing platforms may hinder the realization of data sharing. In this article, a decentralized IIoT data-sharing scheme based on blockchain and edge computing is proposed. A Proof of Storage and Transmission (PoST) consensus mechanism is proposed to meet data storage and transmission requirements of data owners in IIoT data-sharing networks. Based on the manufacture ties of data owners, shared data request probabilities are derived. The IIoT data sharing interactions between data owners and edge devices are modeled as a multiple-leader and multiple-follower Stackelberg game. The alternating direction method of multipliers (ADMMs) algorithm is used to obtain the optimal IIoT data sharing solutions in a distributed manner. Simulation results show that compared with the cooperative scheme, the total profit of edge devices is maximally increased by 59%, and the total utility of data owners is maximally increased by 52%.
The adoption of blockchain and Distributed Ledger Technology is continuously increasing and offering solutions to various application areas. In the last few decades, much more developments in various features are seen to improve the performance, but still scalability is becoming the bottleneck for the performance enhancement. The scalability problem further leads to severe delays and high costs in a bitcoin network. Nowadays, the real-time transactions in cryptocurrencies need to be scaled up from seven transactions per second to thousands of transactions per second to handle real-life problems in the field of visa, healthcare, flights, etc. In this paper, a detailed study on the scalability issues, Proof of Work, and Practical Byzantine Fault Tolerant in blockchain was given. It also explored and analyzed the recent promising research areas in blockchain scalability such as net neutrality, sharding, side-chain, and off-chain scaling through blockchain distributed networks along with their effects.
The construction of enterprise party construction and big data information platform of party construction need a large number of outstanding talents. In order to better realize the integration of big data technology and party building, enterprises must establish a professional working team to effectively improve team skills. Only by constantly strengthening the skills of professional teams can we effectively realize the integration of party building and big data technology. In this paper, a decentralized storage system based on distributed ledger is proposed, and the optimal file redundancy is given. This method can guarantee the storage performance and reduce the size of redundant data by several times.
Quan Nguyen, André Cronje, Michael Kong, Egor Lysenko · 5 authors
This paper consolidates the core technologies and key concepts of our novel Lachesis consensus protocol and Fantom Opera platform, which is permissionless, leaderless and EVM compatible. We introduce our new protocol, so-called Lachesis, for distributed networks achieving Byzantine fault tolerance (BFT)~\cite{lachesis01}. Each node in Lachesis protocol operates on a local block DAG, namely \emph{OPERA DAG}. Aiming for a low time to finality (TTF) for transactions, our general model considers DAG streams of high speed but asynchronous events. We integrate Proof-of-Stake (PoS) into a DAG model in Lachesis protocol to improve performance and security. Our general model of trustless system leverages participants' stake as their validating power~\cite{stakedag}. Lachesis's consensus algorithm uses Lamport timestamps, graph layering and concurrent common knowledge to guarantee a consistent total ordering of event blocks and transactions. In addition, Lachesis protocol allows dynamic participation of new nodes into Opera network. Lachesis optimizes DAG storage and processing time by splitting local history into checkpoints (so-called epochs). We also propose a model to improve stake decentralization, and network safety and liveness ~\cite{stairdag}. Built on our novel Lachesis protocol, Fantom's Opera platform is a public, leaderless, asynchronous BFT, layer-1 blockchain, with guaranteed deterministic finality. Hence, Lachesis protocol is suitable for distributed ledgers by leveraging asynchronous partially ordered sets with logical time ordering instead of blockchains. We also present our proofs into a model that can be applied to abstract asynchronous distributed system.
The Proof of Stake (PoS) protocol is one of the consensus algorithms for blockchain, in which the integrity of a new block is validated according to voting by nodes called validators. However, due to validator-oriented voting, voting results are likely to be false when the number of validators with wrong votes increases. In the PoS protocol, validators are motivated to vote correctly by reward and penalty mechanisms. With such mechanisms, validators who contribute to correct consensuses are rewarded, while those who vote incorrectly are penalized. In this paper, we consider an incentivization mechanism based on the voting profile of a validator, which is estimated from the voting history of the validator. In this mechanism, the stake collected due to the penalties are redistributed to validators who vote correctly, improving the incentive of validators to contribute to the system. We evaluate the performance of the proposed mechanism by computer simulations, investigating the impacts of system parameters on the estimation accuracy of the validator profile and the amount of validator's stake. Numerical results show that the proposed mechanism can estimate the voting profile of a validator accurately even when the voting profile dynamically changes. It is also shown that the proposed mechanism gives more reward to validators who vote correctly with high voting profile.
Eranga Bandara, Sachin Shetty, Deepak K. Tosh, Xueping Liang
Enterprise-level energy delivery systems (EDSs) depend on different software or hardware vendors to achieve operational efficiency. Critical components of these systems are typically manufactured and integrated by overseas suppliers, which expands the attack surface to adversaries with additional opportunities to infiltrate into EDSs. Due to this reason, the risk management of the EDS supply chain is crucial to ensure that we are knowledgeable about the vulnerabilities in software and hardware components that comprise any critical part, quantifiable risk metrics to assess the severity and exploitability of the attack, and provide remediation solutions that can influence a prioritized mitigation plan. There is a need to realize cyber supply chain risk management for industrial control systems’ hardware, software, and computing and networking services associated with bulk electric system (BES) operations. This article proposes a blockchain-based cyber supply chain provenance platform (“Vind”) for EDSs to realize data provenance in a cyber supply chain ecosystem.
One of the main drivers behind blockchain adoption is a lack of trust among entities serving a common goal, but with different interests. Following the success of Bitcoin, several blockchain platforms have emerged, such as Ethereum and Hyperledger Fabric, to enable conducting distrusted processes in a non-repudiable manner. However, it is not safe to assume the applicability of conventional software design strategies to Blockchain-based solutions. In this paper, we assume an untrusted SLA (service level agreement) relationship between an IoT service provider and its consumer. We adopt Hyperledger Fabric for the purpose of implementing SLA compliance assessment. We design a smart contract that takes blockchain unique features into consideration. The design particularly accounts for the MVCC (multiversion concurrency control) mechanism, which while effective for resolving the double spending problem, causes read-write conflicts when high transmission rates are experienced between the IoT application and the blockchain. Using a fire station event monitoring scenario, we describe our smart contract design and solution for conflicting transactions. We experimentally evaluate our solution and demonstrate clear performance improvements in terms of throughput and latency.
Applications on blockchain are currently limited by the relatively poor performance of the blockchain network such as low TPS, high latency and the resulting high transaction fees. Hence, performance optimization is one crucial problem of blockchain. Focusing on the most prosperous public blockchain Ethereum, we model the on-chain transaction confirmation process with the knowledge of Poisson process and queueing theory, derives the mean transaction-confirmation time, and explores the effect of different transaction fees on latency. We also conduct a numeric simulation of the model, which indicates that the model fits in well with the real world blockchain.
In this paper, we report the measuring outcomes of Hyperledger, a Distributed Ledger, which is the derivation Blockchain Technology. A technique to evaluate Hyperledger in a limited infrastructure is developed. The measured infrastructure consists of 8 nodes with a load of up to 20000 transactions/second. Hyperledger constantly runs all evaluation, namely, for 20,000 transactions, the run time 74.30s, latency 73.40ms latency, and 257 tps. This initial evaluation can provide an overview for practitioners in making choices about the adoption of blockchain technology in their IT systems.
Blockchain is a distributed immutable ledger supporting strong secure transactions across various nodes in a Blockchain network after the mutual consensus of all the nodes in the associated network. Blockchain technology is the foundation technology of various crypto currencies. However, it has the potential to contribute to several mission-critical applications (MCA) or real-time applications such as Healthcare, e-Voting, Government Regulatory to securely regulate business processes or to identify any fictitious business transaction. Unfortunately, Blockchain implementations in MCAs are still being challenged by rigorous requirements. The most pressing among these challenges is scalability. The performance time in the current consensus model (related to scalability) is still questionable, especially in MCAs. That is, the model is lacking in high efficiency in many aspects such as transaction throughput, transaction latency, network bandwidth, and storage, despite strong reliability (in terms of advanced security and privacy) through an immutable shared distributed ledger. Hence, there is an exigent need for a new consensus model which could mitigate the scalability issues in MCAs. This paper is therefore aimed to propose a scalable consensus model to improve the scalability issue in MCA by improving the node syndicating time. This contribution is to elevate MCAs (other than Bitcoin)to positively impacting on social/business environment.
Juan Boubeta-Puig, Jesús Rosa-Bilbao, Jan Mendling
Blockchain provides an immutable distributed ledger for storing transactions. One of the challenges of blockchain is the particular processing of dynamic queries due to accumulating costs. Complex Event Processing (CEP) provides efficient and effective support for this in a way, however, that is difficult to integrate with blockchain. This paper addresses the research challenges of integrating blockchain with CEP. More specifically, we envision an effective development environment in which (i) event-driven smart contracts are modeled in a graphical way, which are, in turn, (ii) automatically transformed into complementary code that is deployed in both a CEP engine and a blockchain network, and then (iii) executed on off-chain CEP applications which, connected to different data sources and sinks, automatically invoke smart contracts when event pattern conditions are met. We follow a classic systems engineering approach for defining the concepts of our system, called CEPchain, which addresses the described requirements. CEPchain was evaluated using a real-world case study for vaccine delivery, which requires an unbroken cold chain. The results demonstrate that our approach can be applied without requiring experts on event processing and smart contract languages. Our contribution simplifies the design of integrated CEP and blockchain functionality by hiding implementation details and supporting efficient deployment.
Arjun Kumar, Adesh Sangoi, Shubham Raj, K. V. D. Kiran
Blockchain, the foundation of Bitcoin, has received extensive attentions in recent days. Blockchain-based applications are springing up, covering numerous fields including financial services, reputation system, Internet of Things (IoT), Healthcare systems, Supply Chain Management and so on. Blockchain serves as an immutable ledger which allows transactions to be securely accomplished via point-to-point connections in a distributed system without the need for a third-party. Since it is decentralized, consensus algorithms keeps hold the integrity of the transactions which are added in the chain. Consensus algorithms are the primary root of the blockchain technology and a good consensus algorithm can guarantee the fault tolerance and security of the blockchain systems. In this article, authors present a novel consensus algorithm for public blockchain which shards the miners based on their performance. Once the sharding of miners is done, the best miner from each shard is chosen to form a Super shard of miners, and then from Super shard, one miner is randomly chosen as a winner miner who will mine the next block in the blockchain network. For sharding, performance history of miners will be maintained in each miner and re-sharding will be done at regular intervals in order to bring fairness in the system. The proposed sharding based consensus algorithm solves one of the main problem of public blockchain which is scalability issue. This performance based consensus algorithm also ensures more fairness, avoids starvation, improves the trust among the miners and enhances the overall performance of the blockchain network.
Performance, security, and privacy are important factors to consider when implementing Blockchain in real-world industrial and governance applications. Blockchain is a Distributed Ledger Technology (DLT) that ensures integrity, immutability, transparency and decentralisation. Various Distributed Ledger Technology platforms have emerged over time. These platforms differ in terms of architecture, access permissions, mathematical models, and consensus algorithms. A performance benchmark for DLTs will aid in analysing them based on performance metrics. This paper presents a comparative analysis of existing benchmarking frameworks for DLT performance evaluation. The paper concludes with future research challenges.
Echidna is a widely used fuzzer for Ethereum Virtual Machine (EVM) compatible blockchain smart contracts that generates transaction sequences of calls to smart contracts. While Echidna is an essentially single-threaded tool, it is possible for multiple Echidna processes to communicate by use of a shared transaction sequence corpus. Echidna provides a very large variety of configuration options, since each smart contract may be best-tested by a non-default configuration, and different faults or coverage targets within a single contract may also have differing ideal configurations. This paper presents echidna-parade, a tool that provides pushbutton multicore fuzzing using Echidna as an underlying fuzzing engine, and automatically provides sophisticated diversification of configurations. Even without using multiple cores, echidna-parade can improve the effectiveness of fuzzing with Echidna, due to the advantages provided by multiple types of test configuration diversity. Using echidna-parade with multiple cores can produce significantly better results than Echidna, in less time.
Educational certificate verification is the process of checking and verifying the certificate legitimacy of graduate students. It is a costly, lengthy, and time-consuming procedure as university authorities invest millions of dollars in maintaining the entire process each year. The employer also takes plenty of time to verify the authenticity of the applicant's certificate. The current certification system provides traditional certificates to the candidates. That's why certificates can be tampered with and lost at any time. Moreover, counterfeiting the certificates by scammers and issued by many illegal institutions makes the process hazardous. People frequently lie about their degrees and qualifications by counterfeiting certificates. A fake certificate generated by skillful scammers is always tough to identify and address as the original one. Therefore, there is a crucial need to upgrade the certification and verification process. This paper introduced a Blockchain-based decentralized DIUcerts platform that offers an easy way to issue, check, and verify educational certificates. Additionally, in DIUcerts, data doesn't have to be stored in one place as each certificate's information is kept in an individual file; entire issuance and verifications are done through the Ethereum platform. With this infrastructure, the cost of maintaining a Blockchain-based certificate verification system could be highly minimized as compared to building a similar application on a centralized database. As a result, DIUcerts can lead to better security, cost savings, and a time-saving platform for educational certificate verification.
In a large-scale sharded blockchain, transactions are processed by a number of parallel committees collaboratively. Thus, the blockchain throughput can be strongly boosted. A problem is that some groups of blockchain nodes consume large latency to form committees at the beginning of each epoch. Furthermore, the heterogeneous processing capabilities of different committees also result in unbalanced consensus latency. Such unbalanced two-phase latency brings a large cumulative age to the transactions waited in the final committee. Consequently, the blockchain throughput can be significantly degraded because of the large transaction's cumulative age. We believe that a good committee-scheduling strategy can reduce the cumulative age, and thus benefit the blockchain throughput. However, we have not yet found a committee-scheduling scheme that works for accelerating block formation in the context of blockchain sharding. To this end, this paper studies a fine-balanced tradeoff between the transaction's throughput and their cumulative age in a large-scale sharded blockchain. We formulate this tradeoff as a utility-maximization problem, which is proved NP-hard. To solve this problem, we propose an online distributed Stochastic-Exploration (SE) algorithm, which guarantees a near-optimal system utility. The theoretical convergence time of the proposed algorithm as well as the performance perturbation brought by the committee's failure are also analyzed rigorously. We then evaluate the proposed algorithm using the dataset of blockchain-sharding transactions. The simulation results demonstrate that the proposed SE algorithm shows an overwhelming better performance comparing with other baselines in terms of both system utility and the contributing degree while processing shard transactions.
Mahdi Mallaki, Babak Majidi, Amirhossein Peyvandi, Ali Movaghar
In the last decade various crypto-currencies opened new doors to a decentralized electronic monetary system. Emergence of new Blockchain platforms, such as Ethereum, introduced new features for the implementation of decentralized software or smart contracts. The applications of blockchain technology for secure and efficient information systems is rapidly increasing. However, due to the limitations of this platform including high computational and storage cost, it is not possible to run sophisticated and computationally expensive software on the blockchain. In this paper, a new framework for execution of smart programs on blockchain called the Smart Program Runner Framework (SPRF) is proposed. The proposed framework works by moving decentralized applications to the off-chain and only storing the hash of the state of the application on-chain. This framework can be implemented by creating a side-chain to an existing blockchain without any modifications. The proposed framework is implemented on Stellar blockchain and has various applications for secure and efficient information systems and can provide the required platform for execution of computationally demanding software on blockchain.
In recent years, the application of distributed computing has become more and more widespread. Volunteer computing has gained people's favor in terms of only requiring low cost to exchange for a large amount of computing power. Volunteer computing is defined as a kind of distributed computing infrastructure with a large number of computers voluntarily provided by the public. The integrated computing and storage resources are collected and processed by a central server. However, for volunteer computing, security issues are of paramount importance due to the computing source provided by the volunteers. The attack on any computer in the volunteer network may have an impact on the whole network. On the other hand, blockchain is a chain storage structure that has been widely used in recent years, and non-tamperability is one of its most important characteristics. Therefore, this research aims to improve the security and credibility of volunteer computing by using blockchain technology. Accordingly, a novel volunteer network is established on the Ethereum test network named Ropsten. Its performance and consumption are evaluated with a neural network used for computing. The results demonstrate that proper security properties of volunteer computing can be guaranteed by the proposed blockchain-based approach, although a comparatively low time cost and commission consumption is required.
Consensus protocols are the essential algorithms to achieve overall network reliability in the distributed system. As the representative of the distributed system, the blockchain applies its specific consensus algorithm to ensure security and consistency in the system. The three main consensus algorithms in the blockchain system now are Proof of Work (PoW), Proof of Stake (PoS), and Delegated Proof of Stake (DPoS). The development process of consensus algorithms illustrates the trend of consensus protocols in the blockchain. This paper analyzes the development of three representative consensus protocols: PoW, PoS, and DPoS. Then we compare the advantages and disadvantages of them and discusses the future direction of consensus protocols.
One of the requirements for mining cryptocurrency (Crypto) is that the secured ledger of the blockchain must be updated. However, updating the secured ledger requires that the miner develop and solve complex mathematical equations in higher orders hexadecimal 64-digit solution called a hash. In addition to this challenge, the mining processes of cryptocurrency are both resource and cost-intensive. The resources required include, but not limited to mining software, hardware, power (energy usage), CPU or compute cycles, and NP-hard problem. Apart from these numerous challenges that are associated with mining cryptocurrency, the amount of speed that is required to mine a single block is core. Cryptocurrency mining speed requirement is significantly important because only miners that can have the fastest mining device are most likely to get the reward (profit) from competing for a block. In this paper, we designed and implemented a model to speed up mining process which is capable of giving miners an advantage to arrive at a block earlier. The novelty of our architecture is that our design is based on high performance computing paradigm where we achieve processor speed up by parallelizing the number of processors p. We experimented by varying p = 4, 8, 16. Our experimental results where we used the MC6800 simulated on Easy68k emulator demonstrate feasibility of our proposed model and prove that speed was an essential key to cryptocurrency mining. Keywords: Cryptocurrency, Blockchain, Architecture, Mining, Speedup, Bitcoin. CISDI Journal Reference Format Allenotor, D. & Oyemade, D. A. (2021): An Optimized Parallel Hybrid Architecture for Cryptocurrency Mining. Computing, Information Systems, Development Informatics & Allied Research Journal. Vol 12 No 1, Pp 95-104 DOI - https://doi.org/ 10.22624/AIMS/CISDI/V12N1P10. Available online at www.isteams.net/cisdijournal
Md. Arafatur Rahman, Mohd Saharudin Abuludin, Ling Xi Yuan, Md. Shohidul Islam · 5 authors
Massive data handling requirement in education Industry 4.0 has attracted interests in the research of microservice architectures due to their scalability, resilience, and elasticity characteristics. This development has been challenged by extensive data exchange required by a set of independent microservices to build a complete application, which could result in increasing risks and exposure to the security and privacy breaches of the data. It is imperative to see that educational data are highly sensitive, critical for ascertaining educational attainment and facilitating credentials for qualification verifications. This article puts forward a new proposal of devising a security and privacy-preserving design mechanism of data transactions in educational microservices leveraging the blockchain technology. The design comprises three phases, namely the blockchain framework, data sending–receiving, and confidentiality-integrity-availability over a secured platform with each phase having detailed mechanisms for algorithm implementation. The proposal is shown to exhibit favorable performance in terms of time cost of publishing, throughput, and latency, and shown to have high survey acceptance in terms of confidentiality, integrity, and availability with approximately 10% improvement from prior blockchain adoption.