Deconstructing Blockchains: A Comprehensive Survey on Consensus, Membership and Structure

TL;DR

This survey simplifies blockchain understanding by deconstructing it into membership, consensus, and structure, providing an evaluation framework to analyze various blockchain systems and clarify their design principles and properties.

Contribution

The paper introduces a framework that decomposes blockchains into three core components, aiding analysis and comparison of diverse blockchain proposals.

Findings

Provides a clear overview of blockchain components

Offers an evaluation framework for blockchain systems

Clarifies design principles and properties of existing blockchains

Abstract

It is no exaggeration to say that since the introduction of Bitcoin, blockchains have become a disruptive technology that has shaken the world. However, the rising popularity of the paradigm has led to a flurry of proposals addressing variations and/or trying to solve problems stemming from the initial specification. This added considerable complexity to the current blockchain ecosystems, amplified by the absence of detail in many accompanying blockchain whitepapers. Through this paper, we set out to explain blockchains in a simple way, taming that complexity through the deconstruction of the blockchain into three simple, critical components common to all known systems: membership selection, consensus mechanism and structure. We propose an evaluation framework with insight into system models, desired properties and analysis criteria, using the decoupled components as criteria. We use this framework to provide clear and intuitive overviews of the design principles behind the analyzed systems and the properties achieved. We hope our effort will help clarifying the current state of blockchain proposals and provide directions to the analysis of future proposals.