If you are new to blockchain and starting to know about it, you may have heard about consensus term many times and may be wondering how this is related to blockchain.
Consensus is one of the most important concept in Blockchain. In this post, we will provide consensus introduction and explain it with very basic example.
Let's take very basic example to understand it. There are 5 young kids playing some math puzzle games and one of them gave below puzzle for others to solve.
X + 55/11 = 89
There are few condition and reward to this puzzle like,
- This puzzle need to be solved in 1 minute.
- Calculator or cell phone or laptops can be used.
- Once it is solved by one, other need not to continue solve rather they need to validate the answer given.
- Who so ever solve the puzzle will get $10.
Once the puzzle is given, everyone try to solve the puzzle and after 30 seconds one of the them raise the hand and say, he solved the puzzle and share the value of X (84) with everyone.
Now others stop the calculations from their end and try to validate the value of X provided by kid who solved the puzzle. They say the value is correct and then the kid who solved the puzzle will get $10.
So, in this example, all 5 kids reached to consensus that value of X is 84.
Now question comes how this apply to Blockchain. Let's understand that.
As we all aware, blockchain is chain of blocks where every block is tied to previous block and contains set of transaction records. Every blockchain has different block structure and you can read more details from below links.
Now these blocks are not getting added by default, the process here is the same as mentioned in below example. Here the miner will solve the mathematical puzzle for the block and then other nodes in the network validate that answer and reach to consensus. once the consensus is reached, block gets added to blockchain.
So, consensus play very vital role in Blockchain. There are different types of consensus algorithm exist in blockchain and we will explain in next few posts.