Proof of Authority (PoA)

Proof-of-Authority (PoA) is an alternative consensus mechanism typically used by large companies and private organizations that want to build closed and permissioned blockchains. Since these private chains don’t require public users for consensus, they don’t need miners to validate transactions. On Proof-of-Authority (PoA) blockchains, a single private key can be used to generate all the blocks and validate all of the transactions.