What Is a “Byzantine Fault Tolerance” (BFT) Consensus Mechanism?

Byzantine Fault Tolerance (BFT) is a property of a distributed system that allows it to reach consensus even if some of the nodes are malicious or fail to operate correctly (Byzantine faults). BFT mechanisms, common in Proof-of-Stake (PoS) systems, ensure that all honest nodes agree on the same state and that the agreement is final.

They typically require a supermajority (e.g. 2/3rds) of honest nodes to function correctly.

This is a crucial design goal for achieving strong, deterministic finality in a decentralized environment.