Consensus Algorithm Security Course

This course introduces blockchain consensus algorithms and discusses the security of two major consensus algorithms.

1 hour, 28 minutes

Course description

Consensus algorithms are essential to a distributed, decentralized ledger, where a network of nodes must agree on an official version of the ledger without a central authority. This course describes the underlying principles of consensus algorithms, how two of the primary consensus algorithms work under the hood and how they can be attacked.


Course Recap

Video - 00:02:00

This video reviews the information covered in this course and introduces the next one.
Attacking Proof of Stake

Video - 00:30:00

This video discusses attacks against Proof of Stake consensus algorithms.
Proof of Stake

Video - 00:12:00

This video introduces the Proof of Stake consensus algorithm and describes how it works.
Attacking Proof of Work

Video - 00:17:00

This video discusses attacks against Proof of Work consensus algorithms.
Proof of Work

Video - 00:10:00

This video introduces the Proof of Work consensus algorithm and describes how it works.
Introduction to Blockchain Consensus Algorithms

Video - 00:14:00

This video introduces some of the fundamental principles behind blockchain consensus algorithms and describes some common ones.
Course Introduction

Video - 00:02:00

This video introduces this course, providing an overview of topics to be covered.

Meet the author

Howard Poston

Howard Poston is a copywriter, author, and course developer with experience in cybersecurity and blockchain security, cryptography, and malware analysis. He has an MS in Cyber Operations, a decade of experience in cybersecurity, and over five years of experience as a freelance consultant providing training and content creation for cyber and blockchain security. He is also the creator of over a dozen cybersecurity courses, has authored two books, and has spoken at numerous cybersecurity conferences. He can be reached by email at or via his website at

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