PROOF OF AUTHORITY

The Proof of Authority consensus mechanism might not be as popular as Proof of Work and Proof of Stake, but it is used by one of the most famous blockchains in the Crypto space Binance Smart Chain. Although it's not the only consensus mechanism used by BSC, it also plays a major role in making BSC as safe and scalable as it is. Proof of Authority was first mentioned by the co-founder of Ethereum blockchain Gavin Wood in 2017.
So how does Proof of Authority work? Compared to other consensus mechanisms we've talked about in this article, Proof of Authority works a bit different. Here in order to be a validator, you have to stake a certain number of tokens as well as your identity and reputation. The choosing process for a validator is very rigorous and complex so that weak and fake validators can be weeded out. Users that eventually make it as validators through the PoA algorithm have an incentive to maintain a high reputation. The incentives motivate the validators to maintain a stable transaction process so as not to tarnish the reputation tied to their real-world identities. As a result, most users appreciate their role as a hard-earned validator. After these validators have been picked, they use a software to organize transactions into blocks, unlike the other consensus mechanisms, they do not have to the active all the time as the process of validation is automated.
Some of the blockchains that use the Proof of Authority consensus mechanism are:
- Binance Smart Chain (BSC)
- VeChain (VET)
- Bitgert.
- Palm Network.
PROS AND CONS OF PROOF OF AUTHORITY
PROS
Scalability: Transactions on blockchains that use the Proof of Authority consensus mechanism are very fast and smooth and this is because of its automated setup.

Security: Any attacker with 51% processing power cannot mount a successful attack on the network. The attacker will need to take control of 51% of the validators whose identities are at risk to turn in in the network which is impossible.
CONS
Centralization: The Proof of Authority traded Decentralization for Scalability. It is considered to be centralized because the validators are pre-approved (chosen).

The identities of validators are known and this could put the validators at risk of corruption which also leads to putting the whole network at risk as well.