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Proof of Authority (PoA)

Proof of Authority (PoA) is a consensus process employed by several blockchain networks to certify and secure transactions. It is a variant of the Proof of Work (PoW) and Proof of Stake (PoS) processes, which are more widely used.

A small group of trusted nodes or validators are appointed as network authority in a PoA consensus method. These organizations are in charge of validating transactions and adding fresh blockchain blocks. PoA depends on a reputation-based method. In contrast to PoS, where validators are chosen based on the amount of cryptocurrency they have. And PoW, where miners compete to solve challenging mathematical puzzles.