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.

Blockchain Technology

Blockchain is a distributed decentralized peer-to-peer network aiming to facilitate the immutability and security of data. Towards the service orientation, blockchain is a collection of distributed blocks having unique hash codes without any point of failure. Each block is stored on distributed ledgers, and transactions with them are secure, transparent, immutable, and traceable. To create a new block and allow a transaction to complete, an agreement between all parties is required. To reach an agreement in a blockchain network, consensus algorithms are used. In this chapter, fundamental principles and algorithms of blockchain networks have been discussed, and a detailed review of the blockchain consensus algorithms PoW, PoS, DPoS, PoET, PoWeight, PoB, PoA, and PoC have been provided including the merits and demerits of consensus algorithms with analysis to provide a deep understanding of the current research trends and future challenges.

Data Integrity Time Optimization of a Blockchain IoT Smart Home Network Using Different Consensus and Hash Algorithms

Data security is a major issue for smart home networks. Yet, different existing tools and techniques have not been proven highly effective for home networks’ data security. Blockchain is a promising technology because of the distributed computing infrastructure network that makes it difficult for hackers to intrude into the systems through the use of cryptographic signatures and smart contracts. In this paper, an architecture for smart home networks that could guarantee data integrity, robust security, and the ability to protect the validity of the blockchain transactions has been investigated. The system model is tested using various sizes of realistic datasets (30, 3 k, and 30 k to represent a small, medium, and large number of transactions, respectively). Four different consensus algorithms were considered, the conventional schemes concatenated hash transactions (CHT) and Merkle hash tree (MHT), as well as the newly proposed odd and even modified MHT (O&E MHT) and modified MHT (MMHT). Moreover, 15 hash functions were also examined and compared to understand the effects of each consensus algorithms on the data integrity verification check execution time and the time optimization provided by the proposed MMHT algorithm. The results show that even though the CHT algorithm gives the lowest execution time, it is impractical for a blockchain implementation due to the requirement to copy the entire blockchain ledger in real time. Meanwhile, the O&E MHT does not give any tangible benefit in the execution time. However, the proposed MMHT offers a minimum of 30% gain in time optimization than the conventional MHT algorithm typically used in blockchains. This work shows that the proposed MMHT consensus algorithm not only can identify malicious codes but has an improved data integrity check performance in smart homes, all while ensuring network stability.

Mathematical Analysis of Parametric Characteristics of the Consensus Algorithms Operation with the Choice of the Most Priority One for Implementation in the Financial Sphere

Blockchain is one of the leading data transfer technologies that eliminate the need for centralized management through consensus algorithms. This article describes the consensus algorithms, their benefits, and their applications within a micropayment system in the financial sector. Preliminary studies have shown that the performance of distributed databases largely depends on the chosen consensus algorithm. The main task of the study is to create a mathematical model to assess their performance. The most popular crypto projects and the consensus algorithms are analyzed to determine their performance. The obtained model was tested by calculating the parameters of the distributed register based on the directed acyclic graph algorithm and calculating the parameters of other algorithms used. The result is a mathematical model for evaluating the parametric characteristics of the work of consensus algorithms with the choice of the most priority one for implementation in the financial sector. The analysis focuses on the mathematical steps taken by each consensus algorithm. The data obtained using the developed mathematical model demonstrates that PoW, PoS, and DAG algorithms depend on various resources, such as computing power, the number of connected nodes, and the speed of receiving transactions.