Byzantine Fault Tolerance (BFT)

What Is Byzantine Fault Tolerance (BFT)?

Byzantine Fault Tolerance (BFT) is a computer system attribute that permits it to reach consensus despite the collapse of some of its components. The Byzantine Generals' Problem is a well-known abstraction that illustrates one of the key challenges in computer science, particularly in networked computer systems (For example, cryptocurrency).

Consider numerous Byzantine generals stationed around an enemy city, communicating exclusively through messengers. They must decide whether to attack or withdraw from the city as a group. Some of the generals, though, are rebels and may work actively against reaching an agreement. 

Is it possible to create a mechanism that ensures loyal generals agree on a single course of action irrespective of which generals are traitors? A careful examination of the problem reveals that such an algorithm is feasible only if more than two-thirds of the generals are loyal. 

Diving Deep Into the Concept of Byzantine Fault Tolerance (Bft)

Decentralized cryptocurrencies, such as Bitcoin (BTC), are distributed computer systems. Their networks are made up of individual nodes run by unaffiliated people or organizations that compete to conduct payments and add them to the blockchain's conclusion. 

With nodes geographically distant and autonomous of each other or any centralized administration, it is hard to determine which nodes produce erroneous transaction information – purposefully or accidentally.

The Byzantine Fault Tolerance is a quality of a distributed system that allows it to address these challenges and build stable agreement despite the reality that some nodes dispute with the others, either mistakenly or on purpose. Technical solutions, such as Bitcoin's proof-of-work method, can do this, but only until more than two-thirds of nodes stay loyal to the system.