TL;DR

This paper proposes replacing the trusted central server in federated learning with a blockchain aggregation layer using smart contracts, reputation-based client selection, and token incentives to achieve decentralized, Byzantine-tolerant model training.

Summary

Standard federated learning depends on a trusted central server — a single point of failure for trust and auditability. This paper replaces it with a blockchain layer where smart contracts automate model aggregation and record updates as immutable transactions. Reputation-based client selection filters Byzantine participants before aggregation, and a token incentive mechanism encourages honest gradient contributions. Evaluated on image classification, the system matches centralized FL accuracy while adding auditability and removing the central trust assumption.

Key contributions

  1. Proposes replacing the FL central server with a blockchain aggregation layer using smart contracts for coordination.
  2. Introduces reputation-based client selection as a Byzantine filtering mechanism before gradient aggregation.
  3. Demonstrates a token incentive system that sustains honest participation in open federated networks.
  4. Shows that decentralized aggregation achieves accuracy comparable to centralized FL on image classification benchmarks.

When to cite

  1. When proposing trustless or decentralized federated learning architectures for regulated or adversarial settings.
  2. When discussing smart contracts as transparent, auditable coordination mechanisms for ML aggregation.
  3. When evaluating incentive mechanisms for sustaining honest participation in open FL networks.
  4. When comparing reputation-based Byzantine filtering against cryptographic Byzantine defenses in FL.

FL PET Blockchain ML