# A Simple Single Slot Finality Protocol For Ethereum

## TL;DR

This paper introduces a simple, non-blackbox consensus protocol for Ethereum that achieves single slot finality, reducing reorg risks and enabling faster, more secure transaction confirmation.

## Contribution

It proposes a novel combination of synchronous and partially synchronous protocols to achieve block finality within a single slot, improving Ethereum's finality efficiency.

## Key findings

- Finalizes one block per slot
- Reduces reorg vulnerability
- Enables faster transaction confirmation

## Abstract

Currently, Gasper, the implemented consensus protocol of Ethereum, takes between 64 and 95 slots to finalize blocks. Because of that, a significant portion of the chain is susceptible to reorgs. The possibility to capture MEV (Maximum Extractable Value) through such reorgs can then disincentivize honestly following the protocol, breaking the desired correspondence of honest and rational behavior. Moreover, the relatively long time to finality forces users to choose between economic security and faster transaction confirmation. This motivates the study of the so-called single slot finality protocols: consensus protocols that finalize a block in each slot and, more importantly, that finalize the block proposed at a given slot within such slot. In this work we propose a simple, non-blackbox protocol that combines a synchronous dynamically available protocol with a partially synchronous finality gadget, resulting in a consensus protocol that can finalize one block per slot, paving the way to single slot finality within Ethereum. Importantly, the protocol we present can finalize the block proposed in a slot, within such slot.