Tame the Wild with Byzantine Linearizability: Reliable Broadcast, Snapshots, and Asset Transfer

TL;DR

This paper introduces Byzantine linearizability, a new correctness condition for concurrent objects under Byzantine failures, and demonstrates resilient implementations for reliable broadcast, snapshots, and asset transfer from registers.

Contribution

It formalizes Byzantine linearizability and provides the first resilient implementations of key objects from registers under Byzantine failures.

Findings

Resilient implementation of reliable broadcast from registers

Resilient snapshot object from registers

Resilient asset transfer from registers

Abstract

We formalize Byzantine linearizability, a correctness condition that specifies whether a concurrent object with a sequential specification is resilient against Byzantine failures. Using this definition, we systematically study Byzantine-tolerant emulations of various objects from registers. We focus on three useful objects -- reliable broadcast, atomic snapshot, and asset transfer. We prove that there is an $f$-resilient implementation of such objects from registers with $n$ processes $f<\frac{n}{2}$.