Partially Synchronous BFT Consensus Made Practical in Wireless Networks

TL;DR

The paper tackles the challenge of achieving reliable, low-latency Byzantine fault-tolerant consensus in dynamic ad hoc wireless networks under partial synchrony. It introduces ReduceCatch, a two-phase MAC-level protocol that first reduces active participants and then ensures reliable delivery via NACK-based catch, enabling efficient 1-to-N, N-to-1, and N-to-N communication patterns. By adapting PBFT, Tendermint, and HotStuff to wireless settings and validating them on a three-layer testbed with LoRa hardware, the authors demonstrate significant latency and throughput improvements over baseline MAC strategies, especially under high packet loss. The work provides a practical route to deploying BFT consensus in mobile wireless environments and offers a modular testbed and open-source code to accelerate further development and experimentation in this domain.

Abstract

Consensus is becoming increasingly important in wireless networks. Partially synchronous BFT consensus, a significant branch of consensus, has made considerable progress in wired networks. However, its implementation in wireless networks, especially in dynamic ad hoc wireless networks, remains challenging. Existing wireless synchronous consensus protocols, despite being well-developed, are not readily adaptable to partially synchronous settings. Additionally, reliable communication, a cornerstone of BFT consensus, can lead to high message and time complexity in wireless networks. To address these challenges, we propose a wireless communication protocol called ReduceCatch (Reduce and Catch) that supports reliable 1-to-N, N-to-1, and N-to-N communications. We employ ReduceCatch to tailor three partially synchronous BFT consensus protocols (PBFT, Tendermint, and HotStuff) for seamless adaptation from wired to ad hoc wireless networks. To evaluate the performance of the ReduceCatch-enabled consensus protocols, we develop a three-layer wireless consensus testbed, based on which we implement 20 distinct consensus protocols and measure their latency and throughput. The experimental results demonstrate the superiority of the ReduceCatch-based consensus protocol in terms of latency and throughput.

Figures (7)

• Figure 1: An example of packet loss
• Figure 2: Communication patterns based on ReduceCatch. S denotes the sender and R denotes a receiver.
• Figure 3: Multi-Hop topology
• Figure 4: Wireless consensus testbed. (a) Wireless consensus testbed architecture. The black arrows indicate the support relations. (b) Smart car parts breakdown.
• Figure 5: The latency of four consensus algorithms vs. network dynamism