What is Byzantine Fault Tolerance (BFT)?
Byzantine Fault Tolerance is the property of a distributed system that continues operating correctly even when some nodes act maliciously or fail arbitrarily. Blockchains use BFT-style consensus (Nakamoto, PBFT, Tendermint) to agree on state without trusting any single participant.
Why Byzantine Fault Tolerance (BFT) matters
Understanding Byzantine Fault Tolerance (BFT) is part of building a solid mental model of how Bitcoin, blockchain and Web3 systems actually work. Concepts in the Concepts category sit at the foundation of the broader stack — get them right and the rest is far easier.
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Related terms
- Consensus Mechanism — The rules a network uses to agree on the canonical chain.
- Nakamoto Consensus — Bitcoin's consensus rule: follow the chain with the most work.
- Proof of Stake — A consensus mechanism where validators stake capital instead of burning energy.
More concepts terms
- Decentralization — Distributing control across many independent participants.
- Atomic Swap — Trustless cross-chain trade using hash time-locked contracts.
- Bridge — A protocol that moves assets or messages between chains.
- Staking — Locking tokens to secure a network and earn rewards.
- Validator — A node that proposes and attests to blocks in PoS.
- Layer 1 (L1) — A base blockchain network with its own consensus.
- Layer 2 (L2) — A scaling network that settles to a Layer 1.
- Rollup — An L2 that posts transaction data to L1 for security.
Keep exploring
Continue with the full blockchain glossary — 136 terms in total — or read the developer blog and FAQ for deeper context.