Foundations of Blockchain

Linking blocks in a blockchain

As defined in the introductory chapter, a blockchain is a continuously growing collection of blocks that are chained together to form an open ledger by using cryptography as a key ingredient. Each block in the blockchain is given an identity to mark that block as unique, and this is achieved by using the hash functions that will generate a digest for that block. The collision resistance property of the cryptographic hash function, as mentioned in the previous chapter, Chapter 2, A Bit of Cryptography, ensures that it is infeasible to find two blocks that will result in the same hash value. As a result, the hash function guarantees the uniqueness of the identity created for the block.

When a new block is created, ...