Improved PBFT Algorithm For High-Frequency Trading Scenarios of Alliance Blockchain

With the continuous development of blockchain technology and the emergence of application scenarios, consensus algorithms are still the bottleneck restricting the number of network nodes and data writing efficiency that blockchain can support. How to improve the performance of alliance blockchains safely and efficiently has become an urgent problem to be solved at present. For the practical Byzantine fault tolerance algorithm (PBFT) commonly used in alliance blockchains, there are some problems, such as large communication overhead, simple selection of master nodes, and inability to expand and exit nodes dynamically in the network. This paper proposes an improved algorithm tPBFT (trust-based practical Byzantine algorithm), which is suitable for the high-frequency transaction scenario of alliance chains and introduces a trust interest scoring mechanism between network nodes to adjust the list of consensus nodes dynamically, simplify the PBFT consensus process and reduce the interaction overhead between network nodes. Theoretical analysis and experiments show that the improved tPBFT algorithm can effectively reduce the amount of information interaction between nodes, improve consensus efficiency and support more network nodes.

A blockchain-based cooperative modeling method for digital twin ontology model of the mechanical product

With the rapid increase of multi-source heterogeneous dynamic data of mechanical products, the digital twin technology is considered to be an important method to realize the deep integration of product data and intelligent manufacturing. As a digital archive of the physical entity in entire life cycle, the mechanical product digital twin model is cross-phased and multi-domain. Therefore, safe and stable cooperative modeling has become a basic technical problem that needs to be solved urgently. In this paper, we proposed a blockchain-based collaborative modeling method for the digital twin ontology model of mechanical products. First, an authorization network was constructed among stakeholders. Then modeling processes of the digital twin were mapped to ontology operations and formatted through extensible markup language. Finally, consensuses were obtained based on practical byzantine fault tolerance. And a material modification process of a helicopter damper bearing was taken as an example to verify. The proposed method enables all participants to accurately obtain the latest state of the digital twin model, and has the advantages of tamper-proof, traceability, and decentralization.

Intrusion Detection Analysis of Internet of Things considering Practical Byzantine Fault Tolerance (PBFT) Algorithm

In order to improve the security performance and accuracy of the Internet of things in the use process, it is necessary to use the Internet of things intrusion detection method. At present, the problem of inconsistency between the accuracy of detection results and nodes is more prominent when the Internet of things intrusion detection methods are running. This paper proposes a practical Byzantine fault-tolerant intrusion detection method for the use process of the Internet of things. This method introduces the intrusion detection method and the operation function of foreign attackers on the basis of practical Byzantine fault tolerance; using the expected utility function to the corresponding benefit function of practical Byzantine fault tolerance, the results of Internet of things intrusion detection model can be effectively calculated. Finally, the experimental results show that compared with the existing intrusion detection methods, the proposed method can effectively reduce the energy consumption of the Internet of things in the operation process, can effectively reduce 14.3% and 7.8%, and can effectively reduce the energy consumption of the Internet of things in the operation process.

Practical Byzantine Consensus for Internet-of-Things

Use of IoT/WSN assisted smart-systems in the current age is making our living much more easier. However, components of such systems bear a high chance of getting compromised which may result in a substantial damage or loss. Use of fault tolerant consensus protocols provides a way towards solving this problem. Existing solutions for IoT/WSN systems mostly assume simple non-Byzantine node failures which is not enough to solve the problem. To combat the presence of smart devices with malicious intention, Byzantine fault tolerance support is highly essential in building trustworthy decentralised system. Byzantine fault tolerance has not been addressed much in the context of IoT/WSN because of its inherent requirement of extensive data sharing among the nodes. In this work, we approach to bring a solution to the problem using synchronous communication. In particular, we recast the well-known \textit{Practical Byzantine Fault Tolerant} (PBFT) consensus strategy to an efficient form that is suitable for use in IoT/WSN systems. We demonstrate that our proposed design can work upto 80% faster and consume upto 82% lesser energy compared to a naive implementation of the strategy in publicly available IoT/WSN testbed having 45 nodes.<br>

Practical Byzantine Consensus for Internet-of-Things

Use of IoT/WSN assisted smart-systems in the current age is making our living much more easier. However, components of such systems bear a high chance of getting compromised which may result in a substantial damage or loss. Use of fault tolerant consensus protocols provides a way towards solving this problem. Existing solutions for IoT/WSN systems mostly assume simple non-Byzantine node failures which is not enough to solve the problem. To combat the presence of smart devices with malicious intention, Byzantine fault tolerance support is highly essential in building trustworthy decentralised system. Byzantine fault tolerance has not been addressed much in the context of IoT/WSN because of its inherent requirement of extensive data sharing among the nodes. In this work, we approach to bring a solution to the problem using synchronous communication. In particular, we recast the well-known \textit{Practical Byzantine Fault Tolerant} (PBFT) consensus strategy to an efficient form that is suitable for use in IoT/WSN systems. We demonstrate that our proposed design can work upto 80% faster and consume upto 82% lesser energy compared to a naive implementation of the strategy in publicly available IoT/WSN testbed having 45 nodes.<br>

Hyperledger Healthchain: Patient-Centric IPFS-Based Storage of Health Records

Blockchain-based electronic health system growth is hindered by privacy, confidentiality, and security. By protecting against them, this research aims to develop cybersecurity measurement approaches to ensure the security and privacy of patient information using blockchain technology in healthcare. Blockchains need huge resources to store big data. This paper presents an innovative solution, namely patient-centric healthcare data management (PCHDM). It comprises the following: (i) in an on-chain health record database, hashes of health records are stored as health record chains in Hyperledger fabric, and (ii) off-chain solutions that encrypt actual health data and store it securely over the interplanetary file system (IPFS) which is the decentralized cloud storage system that ensures scalability, confidentiality, and resolves the problem of blockchain data storage. A security smart contract hosted through container technology with Byzantine Fault Tolerance consensus ensures patient privacy by verifying patient preferences before sharing health records. The Distributed Ledger technology performance is tested under hyper ledger caliper benchmarks in terms of transaction latency, resource utilization, and transaction per second. The model provides stakeholders with increased confidence in collaborating and sharing their health records.

A Three-Tier Authentication Scheme for Kerberized Hadoop Environment

Apache Hadoop answers the quest of handling Bigdata for most organizations. It offers distributed storage and data analysis via Hadoop Distributed File System (HDFS) and Map-Reduce frameworks. Hadoop depends on third-party security providers like Kerberos for its security requirements. Kerberos by itself comes with many security loopholes like Single point of Failure (SoF), Dictionary Attacks, Time Synchronization and Insider Attacks. This paper suggests a solution that aims to eradicate the security issues in the Hadoop Cluster with a focus on Dictionary Attacks and Single Point of Failure. The scheme roots on Secure Remote Password Protocol, Blockchain Technology and Threshold Cryptography. Practical Byzantine Fault Tolerance mechanism (PBFT) is deployed at the blockchain as the consensus mechanism. The proposed scheme outperforms many of the existing schemes in terms of computational overhead and storage requirements without compromising the security level offered by the system. Riverbed Modeller (AE) Simulation results strengthen the aforesaid claims.

Renewable Energy Certificate Trading via Permissioned Blockchain

With the continuous advancement of the green certificate trading mechanism, information verification needs to span multiple departments, which causes the application process cumbersome and human errors. In order to solve problems of cumbersome issuance process of the renewable energy certificate (REC) and the inflexible pricing mechanism, in this paper, a hybrid REC trading system was proposed based on an permissioned blockchain technology (BT), which combined advantages of the BT and the continuous double auction (CDA). The operation process of the system was introduced in detail, and the view change protocol in the Practical Byzantine Fault Tolerance algorithm was revised according to the characteristics of the system to improve the system stability. The continuous double auction rule was also introduced in the system. And corresponding bidding strategies were designed to maximize the revenue of users (buyer and seller) and transaction probability. The simulation experiment proves that the bidding mechanism can flexibly adjust the REC price according to the supply and demand relationship. At the same time, the effectiveness and feasibility of trading rule and bidding strategy were also verified.

μDFL: A Secure Microchained Decentralized Federated Learning Fabric atop IoT Networks

<div>Federated Learning (FL) has been recognized as a privacy-preserving machine learning (ML) technology that enables collaborative training and learning of a global ML model based on the aggregation of distributed local model updates. However, security and privacy guarantees could be compromised due to malicious participants and the centralized aggregation manner. Possessing attractive features like decentralization, immutability and auditability, Blockchain is promising to enable a tamper-proof and trust-free framework to enhance performance and security in IoT based FL systems. However, directly integrating blockchains into the large scale IoT-based FL scenarios still faces many limitations, such as high computation and storage demands, low transactions throughput, poor scalability and challenges in privacy preservation. This paper proposes uDFL, a novel hierarchical IoT network fabric for decentralized federated learning (DFL) atop of a lightweight blockchain called microchain. Following the hierarchical infrastructure of FL, participants in uDFL are fragmented into multiple small scale microchains. Each microchain network relies on a hybrid Proof of Credit (PoC) block generation and Voting-based Chain Finality (VCF) consensus protocol to ensure efficiency and privacy-preservation at the network of edge. Meanwhile, microchains are federated vie a high-level inter-chain network, which adopts an efficient Byzantine Fault Tolerance (BFT) consensus protocol to achieve scalability and security.</div><div>A proof-of-concept prototype is implemented, and the experimental results verify the feasibility of the proposed uDFL solution in cross-devices FL settings with efficiency, security and privacy guarantees.</div>