How Does PoA’S Reliance on Identity Differ from PoW’s Reliance on Computational Power?

Proof-of-Authority (PoA) relies on the known identity and reputation of the validators, who are pre-selected and explicitly trusted. Security is maintained by the risk of reputational damage or legal penalty for misbehavior.

Proof-of-Work (PoW) relies on anonymous participants expending computational power to solve a complex puzzle. Security is maintained by the high cost of acquiring enough computing power to execute a 51% attack.

PoA is permissioned; PoW is permissionless.