The Nakamoto’s solution to running a network of distributed nodes without relying on a trusted third party led to birth of Blockchain technology. At the time, his solution was relying on provable cryptographic hashes. That’s why his method was named Proof of Work, where the worker can prove that they have indeed worked. However, his solution came up with a problem: too much energy consumption. This problem made other researches look for new ways to establish consensus, without consuming too much energy and PoS was born. Read more about Pow & PoS on our article here.
Even though PoW & PoS both offer participation of the individuals on the block generation, they bring miner associated risks to the blockchain. It is the main reason why it is still risky and not cost effective for businesses to integrate their products and services with blockchain but fear not, Proof of Authority (PoA) is there for us!
Proof of Authority
As the name states, proof of authority (PoA) based consensus algorithms rely on an authority for block generation. Even though this might seem a blocker for the decentralization, most PoS based blockchains already rely on service providers like AWS and PoW based blockchains are already dominated by large pools.
Proof of Authority consensus eliminates that risk by blocks being generated by the authority, in our case, by the team behind the omchain network. Any user is allowed to run a node themselves too in order to keep the records of the blocks and make sure that no block is being modified by the block generator and there happens no block reorganizations.
On the other hand blocks being generated by the authority allows shorter block generation intervals and more transactions to be processed in the blocks. For that reason, it becomes the most reliable consensus protocol for the sustainable blockchain usage.
How does it work?
There are different algorithms for sustaining a PoA based blockchain. Namely; QBFT, IBFT, IBFT2, Clique and many more. Each of those consensus algorithms have differences in terms of how nodes communicate with each other and how to sustain security. PoA based consensus algorithms are called Byzantine Fault Tolerant if the algorithm is resistant to the byzantine generals attack.
In general rights to generate new blocks are awarded to nodes that have proven their authority to do so in PoA. To gain this authority and a right to generate new blocks, a node must pass a preliminary authentication, often provided by the project’s owner or the team.
Advantages of PoA Consensus
Compared to other consensus types that require a proof of spent computational resources (Proof-of-Work) or an existing “share” (Proof-of-Stake), PoA consensus has several notable advantages:
- High-performance hardware is not required. Compared to PoW consensus, PoA consensus does not require nodes to spend computational resources for solving complex mathematical tasks.
- The interval of time at which new blocks are generated is predictable. For PoW and PoS consensuses, this time varies.
- High transaction rate. Blocks are generated in a sequence at appointed time interval by authorized network nodes. This increases the speed at which transactions are validated.
- Tolerance to compromised and malicious nodes, as long as 51% of nodes are not compromised. Apla implements a ban mechanism for nodes and means of revoking block generation rights.
To learn more about omchain and how our infrastructure works, visit documentation