Digital Signature
What is Digital Signature?
Digital SignatureA public-key cryptographic mechanism that proves the authenticity, integrity and non-repudiation of a message or document.
A digital signature is produced by hashing a message and encrypting that hash with the signer's private key; anyone with the corresponding public key can verify the signature, providing authentication, integrity, and non-repudiation. Common algorithms include RSA-PSS, RSA-PKCS#1 v1.5, ECDSA (over P-256/P-384), EdDSA (Ed25519, Ed448) and the NIST post-quantum signature ML-DSA (CRYSTALS-Dilithium). Digital signatures underpin TLS certificates, code signing, software updates, blockchain transactions, and email standards like S/MIME and DKIM. Their security relies on the hardness of factoring or discrete-logarithm problems and on collision-resistant hash functions; quantum computers would break classical schemes, motivating the ongoing migration to ML-DSA and SLH-DSA.
● Examples
- 01
TLS server certificates are issued and validated using ECDSA or RSA signatures.
- 02
Apple notarisation signs macOS binaries to assure users they come from a known developer.
● Frequently asked questions
What is Digital Signature?
A public-key cryptographic mechanism that proves the authenticity, integrity and non-repudiation of a message or document. It belongs to the Cryptography category of cybersecurity.
What does Digital Signature mean?
A public-key cryptographic mechanism that proves the authenticity, integrity and non-repudiation of a message or document.
How do you defend against Digital Signature?
Defences for Digital Signature typically combine technical controls and operational practices, as detailed in the full definition above.
What are other names for Digital Signature?
Common alternative names include: Cryptographic signature, Public-key signature.