In this session, we have discussed the consensus mechanism of blockchain. we try to explain what is consensus protocol, why do we use it on blockchain.
Consensus protocol protects us in two way
1.Prevent attacks
2.Competing chain problem
Types of Consensus protocol:
1.Proof of work(POW)
2.Proof of stake(POS)
3. PBFT (Practical Byzantine Fault Tolerance)
4. DAG (Directed Acyclic Graph)
proof of work(POW):
Blockchain is a consist of lots of nodes or miner.if we want to add new block in the network ,then miner have to solve the mathematical equation and which miner solve it first is called POW.if 50% up nodes or miner validate it then new block is added to the network.
Concern:-i)lots of energy usage cause only one miner solve it but rest of them are trying butcan’t solve but as their energy is usage which is completely waste
.ii) if more miners collaborate with one another and try to solve the puzzle then51% attack can be happen which is bad for the decentralized
proof of stake(POS):
proof of stake solves the proof of work’s problem. Here one node is randomly chosen who will only mine and solve the mathematical puzzle. Here its called a validator. To become a validator, a node has to deposit stake. If the stake size is big then it has agreat chance of mining. Validator loses stake if they approve fraud transaction.