Trading off $t$-Resilience for Efficiency in Asynchronous Byzantine Reliable Broadcast

TL;DR

This paper introduces a simple, efficient asynchronous reliable broadcast algorithm that offers a tradeoff between resilience and communication cost, requiring fewer messages and steps for systems with up to less than a fifth of processes being Byzantine.

Contribution

It presents a new reliable broadcast algorithm that reduces communication steps and messages while tolerating up to less than one-fifth Byzantine processes, improving efficiency over existing solutions.

Findings

Requires only two communication steps and $n^2-1$ messages.

Tolerates up to $t<n/5$ Byzantine processes.

Offers a resilience-efficiency tradeoff compared to Bracha's algorithm.

Abstract

This paper presents a simple and efficient reliable broadcast algorithm for asynchronous message-passing systems made up of $n$ processes, among which up to $t<n/5$ may behave arbitrarily (Byzantine processes). This algorithm requires two communication steps and $n^2-1$ messages. When compared to Bracha's algorithm, which is resilience optimal ($t<n/3$) and requires three communication steps and $2n^2-n-1$ messages, the proposed algorithm shows an interesting tradeoff between communication efficiency and $t$-resilience.