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Byzantine Fault Tolerance (BFT) is a new consensus algorithm for the Lisk protocol. BFT is designed to guarantee that a particular block is never reverted. It tries to recover from forks as quickly as possible to grow the network chain with better finality. Each node does not only maintain the blockchain, it also maintains additional metadata in memory to validate and verify blocks. This information will also be partially persisted on the blockchain itself, to make sure that a node can rebuild this in-memory dataset if it crashes.