Is Ethereum blockchain really temper proof or immutable?

Question

Suppose there is a user A which transfers some ethers to user B through a proper transaction.
So is it possible to alter the transaction. Something like going back to the block which contains the transaction and creating another chain with a new transaction in which ethers are not sent to User B. So, will the second transaction override the first one.
In short, I want to know what will happen to both of the transaction and how the blockchain will discard one and will keep the other?

Ismael · Answer

It is possible to rewrite blockchain history and replace a transaction by another one. To do so you have to replace already mined blocks by new ones and this new "fork" has to have a larger proof of work.
Your need to have more computation power than the honest miners. This attack is called a 51% attack.

Is Ethereum blockchain really temper proof or immutable?

One Answer

Add your own answers!

Ask a Question