Cryptography And Security In Blockchain

Cryptography And Security In Blockchain

Cryptography and Security in Blockchain Fundamentals of Cryptography Cryptography plays a central role in blockchain technology, ensuring data integrity, privacy, and security. The blockchain is a distributed ledger, and cryptography is used to safeguard transactions and to maintain the trustworthiness of the data being recorded across many decentralized nodes. Here's a breakdown of the fundamentals of cryptography in the context of blockchain: 1. Hash Functions Hash functions are a type of cryptographic algorithm that takes an input and produces a fixed-size string of characters, which is typically a hexadecimal number. These functions are designed to be fast, deterministic (always producing the same output for the same input), and irreversible (impossible to retrieve the original input from the hash value). Purpose in Blockchain : Hash functions are used to create a "fingerprint" of the transaction data. In a blockchain, each block contains a hash of the previous block, creating a chain of blocks (hence, the name "blockchain"). This ensures data integrity—if a piece of data is altered, its hash changes, and the entire chain becomes invalid. Example : SHA-256 (Secure Hash Algorithm 256-bit) is a commonly used hash function in Bitcoin and other blockchain platforms. 2. Public Key Cryptography (Asymmetric Encryption)

Updated July 15, 2026