Is the blockchain secure?
Blockchain technology solves security and trust issues in several ways. New blocks are always stored linearly. They are always added to the “end” of the blockchain. If you look at the Bitcoin blockchain, you will see that each block has a position in the chain called “High”. As of November 2020, the block height has reached 656,197 blocks.
After adding a block to the end of the blockchain, it is difficult to go back and change the contents of the block unless most people reach a consensus. This is because each block contains its own hash value, the hash value of the previous block and the timestamp mentioned above. A hash code is created by a mathematical function that converts digital information into a sequence of numbers and letters. If the information is manipulated in any way, the hash code also changes.
Because it is important for safety. Suppose a hacker wants to modify the blockchain and steal bitcoins from other people. If they choose to change their unique copy, it will no longer match anyone else’s copy. When other people cross your copy with each other, they will find that the copy is noticed and the pirated version of the chain is considered illegal and discarded.
A successful hack of this type requires the hacker to simultaneously control and modify 51% of the blockchain copies so that the new copy becomes the majority copy or agreed chain. Such attacks also require a large amount of resources and resources because they have to process all the blocks because they now have different timestamps and hash codes.
Due to the size and growth rate of the Bitcoin network, the costs of performing this feat are insurmountable. Not only can it be very expensive, it can also be useless. This is not ignored as network members will see such drastic changes in the blockchain. The network member then forks to the new unaffected version of the chain.
This will cause the attacked version of Bitcoin to lose its value, ultimately rendering the attack futile as bad people control useless assets. The same thing would happen if bad guys wanted to attack the new Bitcoin fork. It is designed so that participating in the network is more of a financial challenge than an attack.
Bitcoin and Blockchain
The purpose of the blockchain is to allow the recording and dissemination of digital, but not editable, information. Blockchain technology was first proposed in 1991 by Stuart Haber and W. Scott Storneta. These two researchers want to implement a system that cannot change the labeling of temporary documents. But it wasn’t until 20 years later, with the introduction of Bitcoin in January 2009, that blockchain got its first practical application.
The Bitcoin protocol is based on the blockchain. In a research paper on digital currencies, the creator of the pseudonym Bitcoin, Satoshi Nakamoto, described it as “a new system for equivalent electronic money without a reliable third party”.
The key to understand here is that Bitcoin only uses the blockchain to transparently record the ledger, but in theory blockchain can be used to record any number of data points without exception. As noted above, this could be a transaction, a vote, a product inventory, a government identification, a residency deed, etc.
Today there are many blockchain-based projects that hope to implement blockchain in such a way that, apart from capturing transactions, it will help society. The invariability of the blockchain means fraudulent voting becomes more difficult.
For example, blockchain based decentralization system can be used for a voting system. Each candidate then receives a specific address in the wallet, and voters send their token or cryptocurrency to the address of each candidate they wish to vote for. The transparency and traceability of the blockchain will eliminate the need for manual counting of votes and the ability for poor participants to manipulate physical votes.