Assessing Security and Performances of Consensus algorithms for Permissioned Blockchains

TL;DR

This paper evaluates the security and performance of various consensus algorithms used in permissioned blockchains, highlighting the need for formal security analysis and trust assumptions.

Contribution

It provides a comprehensive assessment of consensus algorithms in permissioned blockchains, emphasizing the importance of formal security analysis and trust models.

Findings

Certain algorithms show better performance in specific scenarios.

Many algorithms lack formal security proofs.

Trust assumptions vary significantly across algorithms.

Abstract

Blockchain is a novel technology that is rising a lot of interest in the industrial and re- search sectors because its properties of decentralisation, immutability and data integrity. Initially, the underlying consensus mechanism has been designed for permissionless block- chain on trustless network model through the proof-of-work, i.e. a mathematical challenge which requires high computational power. This solution suffers of poor performances, hence alternative consensus algorithms as the proof-of-stake have been proposed. Conversely, for permissioned blockchain, where participants are known and authenti- cated, variants of distributed consensus algorithms have been employed. However, most of them comes out without formal expression of security analysis and trust assumptions because the absence of an established knowledge. Therefore the lack of adequate analysis on these algorithms hinders any cautious evaluation of their effectiveness in a real-world setting where systems are deployed over trustless networks, i.e. Internet ...