Byzantine Fault Tolerance
Web3 / infrastructure applications
Byzantine Fault Tolerance (BFT) is a property of distributed systems that enables them to reach consensus and continue operating correctly even when some nodes fail, behave erratically, or act maliciously. Named after the historical "Byzantine Generals Problem," BFT ensures that a network can maintain agreement on the current state as long as the majority of nodes remain honest. This is fundamental to blockchain systems because nodes do not inherently trust one another, yet must collectively validate transactions and maintain a single authoritative ledger. Different consensus mechanisms implement BFT through various voting and validation schemes. Example: Tendermint is a Byzantine Fault Tolerant consensus engine that powers the Cosmos ecosystem. It uses a round-robin validator selection process where nodes vote on blocks, and consensus is reached when two-thirds of validators agree, allowing the network to tolerate up to one-third of validators being offline or dishonest. Why it matters for blockchain infrastructure: BFT is essential for blockchain security because it guarantees that malicious actors cannot unilaterally control the network or forge false transactions. Without Byzantine Fault Tolerance, a blockchain could be compromised by coordinated attacks or node failures, making it unreliable for storing value.
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