암호학적 해시 함수
데이터를 고정된 길이의 고유한 문자열로 변환하는 알고리즘.
In blockchain, hash functions link blocks together (the hash of the previous block is included in the current block), creating an immutable chain. They also protect passwords, verify file integrity, and enable digital signatures.
graph LR
Center["암호학적 해시 함수"]:::main
Pre_cryptography["cryptography"]:::pre --> Center
click Pre_cryptography "/terms/cryptography"
Pre_computer_science["computer-science"]:::pre --> Center
click Pre_computer_science "/terms/computer-science"
Pre_algorithm["algorithm"]:::pre --> Center
click Pre_algorithm "/terms/algorithm"
Rel_bitcoin["bitcoin"]:::related -.-> Center
click Rel_bitcoin "/terms/bitcoin"
Rel_blockchain["blockchain"]:::related -.-> Center
click Rel_blockchain "/terms/blockchain"
Rel_proof_of_work["proof-of-work"]:::related -.-> Center
click Rel_proof_of_work "/terms/proof-of-work"
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classDef child fill:#0f172a,stroke:#10b981,color:#94a3b8,rx:5,ry:5;
classDef related fill:#0f172a,stroke:#8b5cf6,stroke-dasharray: 5 5,color:#94a3b8,rx:5,ry:5;
linkStyle default stroke:#4b5563,stroke-width:2px;
🧒 5살도 이해할 수 있게 설명
데이터를 넣으면 고유한 '번호표'를 만들어주는 기계입니다. 파일 내용이 조금이라도 바뀌면 이 번호표가 아예 다르게 변해요.
🤓 Expert Deep Dive
Cryptographic hash functions like SHA-256 and Keccak-256 are the workhorses of blockchain. They underpin Proof of Work (finding a hash below a target), Merkle Trees (efficient data verification), and Address Generation (deriving public keys). Security depends on Pre-image Resistance (difficult to find input from output) and Collision Resistance (difficult to find two inputs with same output). As quantum computing advances, older standards like MD5 and SHA-1 have been deprecated due to collision vulnerabilities, driving the move towards SHA-3 and quantum-safe algorithms.