What Is Blockchain Technology and How Does It Function?Part-2

 Decentralization of the Blockchain

A blockchain is a method of distributing the data stored in a database across the nodes that make up a network of computers or other devices that are running blockchain software. It ensures that the data is accurate. If someone tries to update a record in a file within the database, for instance, other nodes will block it from taking effect to ensure the integrity of the data. Because of this, no one is able to alter the data that is stored in any of the nodes that make up the network.

Because the data is encrypted and the information is distributed in this way, information and history (such as transactions in cryptocurrencies) cannot be changed.

Transparency of the Blockchain 

Because blockchain is a decentralized ledger, all transactions may be viewed in an open and transparent manner by anybody with access to a private node or by utilizing Blockchain Explorer, which makes it possible for anyone to view transactions directly. Every node maintains its own independent copy of the chain, which is kept up to date whenever new blocks are validated and added. This indicates that you have the ability, if you so want, to follow a cryptocurrency wherever it goes. 

Is it safe to use blockchain?
In a number of different ways, blockchain technology has successfully accomplished decentralized security and trust. In the beginning, new blocks are consistently and linearly stored in chronological order. To put it another way, they are invariably added to the "end" of the blockchain. When a new block is placed to the end of the blockchain, all of the blocks that came before it are paused in their progression. They can no longer be modified in any way.

Any modification to the data will result in a new hash for the block it was in. Any modification to one block will result in modifications to the blocks that follow it since each block carries the hash of the previous block. A modified block will be immediately rejected by the network since the modified hash will no longer be compatible with the hashes of the previous blocks.

However, not every blockchain offers the same level of safety. They generate the security layer for which they are famous by the use of code. Exploitation of coding vulnerabilities, as well as hacking of the blockchain itself, are also possible outcomes.

Take, for instance, the scenario in which a hacker controls a node in a blockchain network and intends to change an existing blockchain or create a new one in order to steal bitcoin from other users. In the event that they modify their own node, it is incumbent upon them to persuade other nodes that their copy is accurate. Because the information is dispersed over several different locations.

In order to accomplish this, they need to maintain control over the majority of the network and assemble the nodes at the appropriate time. Because they need to control more than half of the network in order to execute this attack, it is referred to as a "51% Attack."

In this kind of attack, timing will be everything; by the time the hacker makes a move, the network will have probably already secured the blocks they were trying to modify and will have begun to fill additional forward blocks.

The reason for this is that the rate at which these networks generate hashes is noticeably lot faster than other networks.

On April 21, 2023, for instance, the rate at which Bitcoin created hashes was 348.1 exHash (18 zeros after 348.1). This represents one hash every second.

It is therefore possible to say that changing this many blocks of the blockchain simultaneously before new blocks are created is nothing more than a pipe dream.

I hope that by the end of these two parts, everyone has a basic understanding of what "Blockchain" is, how secure and transparent it is, and how it operates through decentralization.