Asynchronous Byzantine Fault Tolerance (aBFT) is a consensus mechanism that improves on typical Byzantine Fault Tolerance (BFT) consensus by solving the Byzantine General's Fault problem in a unique way. Through aBFT, nodes are able to reach consensus independently by making use of a two-stage block confirmation process using a two-thirds supermajority. The first stage proposes a last irreversible block (LIB), while the second stage finalizes the proposed LIB to make the block irreversible. ABFT consensus is considered leaderless, with no independent leading node responsible for block creation and finalization, resulting in a faster and more secure network. The Fantom and Hedera Hashgraph protocols and other networks employ different variations of aBFT.
