One of the great innovations introduced with blockchain was solving the Byzantine Generals Problem: coming to consensus in a setting with many unknown and potentially untrustworthy actors. Consensus mechanisms allow blockchains to achieve just that. Because we want to take a detailed look at the two most researched ways of achieving consensus, we split this topic into two articles:
Consensus in Distributed Systems
In this first article, we look at consensus in distributed systems. What are the main challenges that arise when a system is operated by many unknown actors? And how does one ensure agreement on a common transaction history is reached?
Proof of Work
Proof-of-Work (PoW) was the first consensus mechanism that worked in a distributed environment of untrusted parties. Its principle is based on voting on a version of the history with the weight of your computing power.