# On the correctness of Egalitarian Paxos

## TL;DR

This paper examines a critical correctness issue in Egalitarian Paxos related to replica ballot switching, which can cause divergence and violate linearizability, highlighting the need for correction in the protocol's specification and implementation.

## Contribution

It identifies a specific flaw in Egalitarian Paxos's handling of ballot dependencies that can lead to divergence and correctness violations.

## Key findings

- The flaw can cause replicas to diverge.
- The issue affects the linearizability of the protocol.
- The paper suggests the need for protocol correction.

## Abstract

This paper identifies a problem in both the TLA+ specification and the implementation of the Egalitarian Paxos protocol. It is related to how replicas switch from one ballot to another when computing the dependencies of a command. The problem may lead replicas to diverge and break the linearizability of the replicated service.