Visible to the public The Security Ingredients for Correct and Byzantine Fault-tolerant Blockchain Consensus Algorithms

TitleThe Security Ingredients for Correct and Byzantine Fault-tolerant Blockchain Consensus Algorithms
Publication TypeConference Paper
Year of Publication2020
AuthorsAltarawneh, A., Skjellum, A.
Conference Name2020 International Symposium on Networks, Computers and Communications (ISNCC)
Date PublishedOct. 2020
ISBN Number978-1-7281-5628-6
KeywordsAvailability, blockchain, blockchain security taxonomy, byzantine fault-tolerance, Consensus algorithm, Consensus algorithm security, consistency, Fault tolerance, Fault tolerant systems, liveness, Peer-to-peer computing, pubcrawl, resilience, Resiliency, Safety, Scalability, security

The blockchain technology revolution and the use of blockchains in various applications have resulted in many companies and programmers developing and customizing specific fit-for-purpose consensus algorithms. Security and performance are determined by the chosen consensus algorithm; hence, the reliability and security of these algorithms must be assured and tested, which requires an understanding of all the security assumptions that make such algorithms correct and byzantine fault-tolerant.This paper studies the "security ingredients" that enable a given consensus algorithm to achieve safety, liveness, and byzantine fault tolerance (BFT) in both permissioned and permissionless blockchain systems. The key contributions of this paper are the organization of these requirements and a new taxonomy that describes the requirements for security. The CAP Theorem is utilized to explain important tradeoffs between consistency and availability in consensus algorithm design, which are crucial depending on the specific application of a given algorithm. This topic has also been explored previously by De Angelis. However, this paper expands that prior explanation and dilemma of consistency vs. availability and then combines this with Buterin's Trilemma to complete the overall exposition of tradeoffs.

Citation Keyaltarawneh_security_2020