Proof of Authority (PoA) is a reputation-based consensus mechanism that introduces a practical and scalable solution for blockchains. While PoS means that validators stake coins, the PoA consensus algorithm leverages on the value of identities, which means that block validators are staking their own reputation instead. Therefore, PoA blockchains are validated by the nodes that are selected because of their reputation.
PoA blockchains will only choose a limited number of block validators, making it a highly efficient system. These validators are approved beforehand as valid moderators of the system. As such, PoA is a valid logistical solution for larger blockchain companies.
Benefits of POA
Proof of Authority, as aforementioned, are scalable and efficient options for larger-scale companies. However, it is important for companies to know that there are a few conditions before you can launch a Proof of Authority Consensus
First, validators would need to be valid and trustworthy. They would have to go through thorough screening and put their reputation on the line before becoming a validator. In essence, the validator is a huge part of POA, because without a reputable validator, POA will not work.
Limitations of Proof of Authority
A criticism is that PoA validators expose their identities to the public. This means that the validators can be a target of attack because they hold a large part of the power to the blockchain. For instance, these validators may be hacked, or influenced to act dishonestly.
In Conclusion
Proof of Authority presents itself as a viable alternative compared to Proof of Work and Proof of Stake. Having said this, there are some disadvantages and tradeoffs in the PoA framework. It is important to ensure that the advantages and disadvantages are balanced in any blockchain network.
