Understanding the technical details of how blockchain works can be complex. In this post, we will take a look behind the scenes of blockchain to understand how blocks, hashes, and nodes work together to make this revolutionary technology possible.
Image Credit: Cdac.in
Working of Blocks and Nodes in Blockchain
Blocks in blockchain are the basic unit of data and they hold the information of the transactions that are executed in the network. They are linked together in a chain, forming a secure and unbreakable chain. Each block contains a reference to the previous block, which is called a "hash pointer", and it is this linking that creates the security of the blockchain.
Nodes are the backbone of a blockchain network, they are responsible for maintaining the integrity of the blockchain and ensuring that all the data is accurate and secure. Each node on a blockchain network has a copy of the entire blockchain and helps to validate new transactions and add new blocks to the chain.
When a new transaction is made on the blockchain, it is broadcasted to all the nodes on the network. Each node then verifies the transaction to ensure that it is valid. This verification process typically involves checking the digital signature of the transaction to ensure that it came from the correct sender, and checking to see if the sender has enough funds to complete the transaction.
Once a transaction is verified, it is grouped with other transactions into a new block. The block is then passed through a complex mathematical problem called consensus algorithm, this problem is solved by a node, also called miner, and the first one to solve it, is allowed to add the block to the blockchain and broadcast it to the other nodes.
Once a block is added to the blockchain, it is broadcasted to all the nodes on the network. Each node then verifies the new block by checking the hash of the block and comparing it to the previous block. If the block is valid, the node adds it to its copy of the blockchain. If the block is invalid, the node does not add it to its copy of the blockchain, and it is not considered a part of the blockchain.
The blocks in the blockchain are arranged in a chronological order and once they are added to the chain, they cannot be altered. This is because, in order to alter a block, one would have to alter all the blocks that come after it, and this would require an immense amount of computational power, making it almost impossible to achieve.
In summary, blocks in a blockchain are the basic unit of data, they hold the information of the transactions that are executed in the network, they are linked together in a chain, forming a secure and unbreakable chain and are tamper-proof. The process of adding a block to the blockchain is called mining and it's done through a consensus algorithm, which ensures that the blockchain is accurate and secure. And nodes in a blockchain network are responsible for maintaining the integrity of the blockchain by validating transactions, solving complex mathematical problems, and adding new blocks to the chain, they also keep a copy of the entire blockchain, which ensures that the blockchain is accurate and secure. This process is called consensus, and it's designed to ensure that all nodes on the network have the same copy of the blockchain, and that the blockchain is tamper-proof.
Working of Hash in Blockchain
The working of a hash in blockchain is a crucial aspect of maintaining the integrity and security of the blockchain. A hash is a fixed-length string of characters that is created using a mathematical algorithm. The algorithm takes the data in a block as input, and outputs a unique hash that represents that data.
When a new block is added to the blockchain, the data in the block is passed through a hash function, such as SHA-256. This function takes the data in the block and converts it into a unique hash. This hash is then added to the block, and the block is added to the blockchain.
Once a block is added to the blockchain, the hash of that block becomes a permanent part of the blockchain. If any data in that block is altered, the hash will change, making it easy to detect any tampering with the data. This is because the hash function is a one-way function, meaning that it's not possible to determine the input data from the output hash.
In order to verify that a block has not been tampered with, a node on the blockchain network can calculate the hash of the block using the same hash function, and compare it to the hash that is stored in the block. If the two hashes match, the block is considered to be valid, and it is added to the node's copy of the blockchain. If the two hashes do not match, the block is considered to be invalid, and it is not added to the blockchain.
In summary, the hash function in blockchain is a one-way function, which takes the data in a block as input, and outputs a unique hash that represents that data. This hash is added to the block and become a permanent part of the blockchain. The hash function ensures the integrity of the blockchain by making it easy to detect any tampering with the data in the block.
Blockchain technology is like a digital ledger, where blocks are the pages and hashes are the locks, while nodes are the keepers of the ledger, making sure that everything is accurate and secure.