BlockFL: blockchain-enabled decentralized federated learning and model trading

• Main Author: Pham, Tan Anh Khoa
• Other Authors: Dusit Niyato
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2022
• Subjects: Engineering::Computer science and engineering
• Online Access: https://hdl.handle.net/10356/156495
• Institution: Nanyang Technological University

Federated Learning (FL) is a promising privacy-preserving distributed machine learning paradigm. However, there is only a centralized parameter server to aggregate all the local model updates, which brings the challenges of a single point of failure and server overload, especially in large-scale training scenarios. To achieve secure, reliable, and scalable FL, we leverage a sharding technique to improve scalability of the Blockchain-based Federated Edge Learning (BFEL) framework with a main chain and multiple subchains in [Kang et al., 2020]. Specifically, to release the cross-chain transaction processing workload of the main chain, the number of working consensus nodes for the main chain can be divided into multiple clusters to process multiple cross-chain transactions in parallel. This method helps reduce the execution time for FL task training and improve transaction throughput on the main chain. This project presents a working prototype to utilize blockchain and sharding techniques, thereby scaling up decentralized FL for secure, scalable and large-scale FL task training.