# The Evolution and Optimization Strategies of a PBFT Consensus Algorithm for Consortium Blockchains
## 3 An Introduction to Mainstream Consensus Algorithms
### The Mainstream Consensus Algorithms Used in Consortium Blockchains
#### 3.3.2 Kafka  
Kafka, originally developed by LinkedIn, is a distributed, partitioned, and multi-replicated messaging system coordinated by ZooKeeper. Its most prominent feature is the ability to process large amounts of data in real-time to meet various use case scenarios. Fundamentally, Kafka provides transaction sequencing services alongside fault tolerance \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Author** & **Year** & **Improvement Method** & **Core Mechanism** & **Limitations** \\ \hline \multirow{2}{*}{[PERSON] [63]} & \multirow{2}{*}{2021} & Dynamic Validator & The dynamic election of validation nodes to & Frequent validator changes may introduce \\  & & Selection Optimization & reduce the risk of Sybil attacks. & instability and increase \\ \hline \multirow{2}{*}{[PERSON] [66]} & \multirow{2}{*}{2021} & Consortium Blockchain Carpool & Privacy-preserving transaction validation, & Privacy mechanisms may add computational \\  & & Data Protection & adapted for urban transportation scenarios. & overhead, affecting system efficiency. \\ \hline \multirow{2}{*}{[PERSON] [72]} & \multirow{2}{*}{2021} & Adjacent Voiting & Adjacent voting combined with fuzzy value & Fuzzy value analysis may introduce \\  & & Decentralization Enhancement & analysis to improve fair participation. & ambiguity, impacting decision reliability. \\ \hline \multirow{2}{*}{[PERSON] [65]} & \multirow{2}{*}{2021} & Network Public Opinion & Embedding fairness constraints to ensure the & Enforcing fairness constraints may introduce \\  & & Collaborative Governance & credibility of decision-making. & subjectivity in governance rules. \\ \hline \multirow{2}{*}{[PERSON] [64]} & \multirow{2}{*}{2021} & Anomaly Detection Reward and & Anomaly detection combined with reward & \multirow{2}{*}{Effectiveness depends on the accuracy of \\  & & Punishment Mechanism & self-regulation. & anomaly detection algorithms. \\ \hline \multirow{2}{*}{[PERSON] [67]} & \multirow{2}{*}{2021} & Multi-Robot System & DPoS based on PLTS, optimized for & Requires effective delegation strategies to \\  & & Coordination Protocol & delay-sensitive scenarios. & prevent centralization risks. \\ \hline \multirow{2}{*}{[PERSON] [68]} & \multirow{2}{*}{2022} & \multirow{2}{*}{Industrial IoT Privacy Sharing} & DPoS combined with zero-knowledge proofs & Zero-knowledge proofs can introduce \\  & & & to protect IIoT data. & computational overhead, \\ \hline \multirow{2}{*}{[PERSON] [70]} & \multirow{2}{*}{2022} & Digital Twin Intelligent Traffic & The integration of DPoS with digital twin to & Digital twin modeling requires significant \\  & & achieve real-time consensus. & computational resources for \\ \hline \multirow{2}{*}{[PERSON] [71]} & \multirow{2}{*}{2022} & Federated Learning & Social IoT framework to incentivize data & Effectiveness depends on user participation \\  & & Market incentives & contribution and model integrity. & and incentive distribution fairness. \\ \hline \multirow{2}{*}{[PERSON] [69]} & \multirow{2}{*}{2024} & \multirow{2}{*}{Lightweight IoT Data Management} & Resource-optimized consensus to reduce the & May sacrifice some security guarantees to \\  & & overhead on edge devices. & achieve lower computational overhead. \\ \hline \hline \end{tabular}
\end{table} 
Table 7: A comparison of DPoS consensus optimization. capabilities. For each chain, Kafka assigns a partition and a single partition topic. Ordering nodes can read from the partition to obtain a consistent transaction ordering list across all ordering nodes. When the transaction threshold is reached, batching occurs, generating new blocks. In the event of node failure, alternative ordering nodes can take over to distribute the blocks. All ordering nodes maintain local block logs, ensuring the integrity and security of transaction data. The Hyperledger Fabric open-source platform [73] adopts the Kafka consensus algorithm, benefiting greatly from Kafka's high performance.