SoK: DAG-based Consensus Protocols

TL;DR

This paper systematically analyzes DAG-based consensus protocols, categorizing them by their focus on availability or consistency, and discusses their design trade-offs, security, scalability, and future research directions.

Contribution

It provides a comprehensive classification and analysis of DAG-based consensus protocols, highlighting their core principles, trade-offs, and recent advancements.

Findings

DAG protocols are classified into availability-focused and consistency-focused categories.

Security and scalability challenges are identified and discussed.

Research gaps and future directions for DAG-based consensus are outlined.

Abstract

This paper is a Systematization of Knowledge (SoK) on Directed Acyclic Graph (DAG)-based consensus protocols, analyzing their performance and trade-offs within the framework of consistency, availability, and partition tolerance inspired by the CAP theorem. We classify DAG-based consensus protocols into availability-focused and consistency-focused categories, exploring their design principles, core functionalities, and associated trade-offs. Furthermore, we examine key properties, attack vectors, and recent developments, providing insights into security, scalability, and fairness challenges. Finally, we identify research gaps and outline directions for advancing DAG-based consensus mechanisms.