Читать книгу Blockchain Data Analytics For Dummies - Michael G. Solomon - Страница 36

Blockchain network nodes submit transactions, and then special nodes called miners assemble the transactions into blocks and then compete with other miners to be the first to solve a mathematical puzzle that makes a block easy to verify by all other nodes. The first miner to solve the puzzle gets a small reward for the work.

Each blockchain can define a different method its nodes use to verify blocks, but all the nodes in a specific blockchain network use the same block verification method. Methods that blockchains use to verify the validity of new blocks are called consensus algorithms. A common consensus algorithm is the Proof of Work (PoW) algorithm, which asks miners to expend energy to solve mathematical puzzles in exchange for a prize.

Regardless of the type of consensus a blockchain uses, more than 50 percent of the nodes must agree that a new submitted block is the so-called truth. When a majority agrees, all nodes add the new block to their blockchain. Through consensus and guarantees that no previous data has changed, blockchain technology ensures that all copies of the blockchain are identical and can be trusted.