Voting-based probabilistic consensuses and their applications in distributed ledgers

TL;DR

This paper reviews probabilistic majority dynamics models for consensus in distributed ledgers, highlights their limitations in Byzantine environments, and discusses the FPC protocol that uses external randomness to address these issues.

Contribution

It provides a critical analysis of probabilistic consensus models and introduces the FPC protocol as a practical solution using external randomness.

Findings

Probabilistic models face challenges in Byzantine settings.

External randomness can improve consensus reliability.

Further research is needed for practical Byzantine consensus solutions.

Abstract

We review probabilistic models known as majority dynamics (also known as threshold Voter Models) and discuss their possible applications for achieving consensus in cryptocurrency systems. In particular, we show that using this approach straightforwardly for practical consensus in Byzantine setting can be problematic and requires extensive further research. We then discuss the FPC consensus protocol which circumvents the problems mentioned above by using external randomness.