So far, we have discussed how BABE creates blockchain candidates and GRANDPA finalizes them. We know that we need more than two-thirds of validators to properly follow the protocol.
Blind Assignment for Blockchain Extension (BABE) is a block production engine that was inspired by Ouroboros Praos, another proof-of-stake protocol.
In the introduction to this series, I outlined that a consensus algorithm helps a network of computers answer three questions. GRANDPA addresses the second.
This series will be a discussion about security and consensus in Polkadot. In part 1, we will define some terms before getting into the details of how Polkadot creates and secures blocks.