Data Immutability in Blockchain Network

One of the primary reasons for blockchain's popularity is the data security that it provides. Features like hashing, decentralization, consensus mechanism ensure that there is no data hacking into the system. They also prevent malicious activities in the network. Apart from these features, blockchain offers one more important feature that differentiates it from other networks: Data Immutability. Let’s learn from Shebin what is data immutability and how does blockchain offer this feature in the upcoming video.

Immutability means something that is permanent and cannot be changed. In practical terms, it refers to the extreme difficulty that one will face in trying to alter or make changes to the existing data. Blockchain forms a chain of blocks that are connected to each other via a link also known as the previous hash pointer or simply previous hash. The hash of a block is calculated for all the contents in the block header using a hashing algorithm. Recall that Merkel root is a part of the block header and any change in any constituent transaction results in the change in the Merkel root. Hashing algorithms are deterministic and result in a different output in case the input is changed. Change in the Merkel root will result in changing the hash of the entire block. In case the hash of one block is changed, the block next to it will not have a link to this block as the previous hash will not match the new block. Hence, the link between the blocks will be broken and these blocks will become invalidated.

Immutability is an important feature of the blockchain that helps in data from being manipulated and also helps in identifying malicious nodes in the network.