手法を比較

	SHAハッシュ関数	デジタル署名方式
分野	暗号学	暗号学
系統	Process / pipeline	Process / pipeline
提唱年	1993	1978
提唱者	National Institute of Standards and Technology (NIST)	Ronald Rivest, Adi Shamir, Leonard Adleman
種類	One-way hash algorithm	Asymmetric signature algorithm
原典	National Institute of Standards and Technology (1993). Secure Hash Standard (SHS). Federal Information Processing Standards (FIPS) Publication 180.	Rivest, R. L., Shamir, A., & Adleman, L. (1978). A method for obtaining digital signatures and public-key cryptosystems. Communications of the ACM, 21(2), 120–126.
別名	SHA-1, SHA-256, SHA-512, Secure Hash Algorithm	Digital Signature Algorithm, Message Authentication and Integrity, Public Key Signature
関連	4	4
概要	The Secure Hash Algorithm (SHA) is a family of cryptographic hash functions standardized by NIST starting in 1993. SHA functions produce fixed-length digests from arbitrary-length input data, serving as a fundamental building block for digital signatures, message authentication, and data integrity verification across security-critical applications.	A digital signature scheme provides authentication, integrity assurance, and non-repudiation of electronically signed documents. Using public-key cryptography (such as RSA, DSA, or ECDSA), the originator signs a message with a private key in a way that any recipient can verify the signature using the originator's public key, proving that the message was created by the claimed author and has not been tampered with.