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BFT (Byzantine Fault Tolerance) is called Byzantine Fault Tolerance. Byzantine fault-tolerant technology is a type of fault-tolerant technology in the field of distributed computing. The Byzantine hypothesis is a model of the real world. Due to hardware errors, network congestion or interruption, and malicious attacks, computers and networks may exhibit unexpected behavior. Byzantine fault-tolerant technology is designed to handle these abnormal behaviors and meet the specifications of the problem to be solved.
Byzantine generals problem
Byzantine fault-tolerant technology originates from the Byzantine general problem. The Byzantine Generals problem is a famous example used by Leslie Lamport (Turing in 2013) to describe the Distributed Consensus in the paper.
The Byzantine Empire wanted to attack a powerful enemy, so it sent 10 troops to surround the enemy. Although this enemy is not comparable to the Byzantine Empire, it is also capable of resisting simultaneous attacks by 5 conventional Byzantine armies. These 10 armies attacked simultaneously in a separate state of encirclement. Either of their armies will have no chance of winning a single attack, unless at least 6 armies (more than half) attack at the same time to attack the enemy country. They are scattered around the enemy's country, relying on the communication troops to communicate with each other on horseback to negotiate the attack intention and attack time. The problem that bothers these generals is that they are not sure whether there are traitors among them, and traitors may change their attack intentions or attack time without authorization. In this state, the Byzantine generals can guarantee that more than 6 armies can attack together at the same time and win the battle?