Cryptology Engine

Digital Signatures

ECDSA, RSA-PSS, Ed25519 and other signature algorithms

What is Digital Signatures?

Digital signatures are the digital equivalent of physical signatures. They are used to prove that a document or message was truly created by a specific person or institution and has not been altered. Digital signatures work using asymmetric encryption - the sender signs with a private key, and the receiver verifies with a public key. This way, the integrity of a document and the identity of the sender can be mathematically proven.

Use Cases

  • Software signing
  • Email security
  • Digital documents
  • Blockchain transactions
  • Cryptocurrency transfers
  • Legal documents
  • Identity verification
Key Features
  • Authentication
  • Data integrity
  • Non-repudiation
  • Asymmetric encryption
  • Mathematical proof
Algorithm Comparison
Algorithm
Security
Speed
Use Cases
ECDSA-P256Very HighFast
Example: BlockchainModern applicationsHigh-performance modern systems
ECDSA-P384Very HighMedium
High-security applicationsModern systemsNon-performance-critical, high-security use casesSlower than P-256
Ed25519Very HighVery Fast
Fast, secure defaultHigh-performance applicationsModern security protocols
Ed448Very HighFast
High-security applicationsModern systemsSlower than Ed25519 but higher security
RSA-PSSVery HighSlow
Systems requiring wide compatibilityClassic applications
RSA-PKCS#1 v1.5Not recommended for new designs - should only be used for compatibility with legacy systems. RSA-PSS should be preferred.Slow
Legacy, compatibility onlyCompatibility with legacy systemsNot recommended for new designs

* Comparisons are relative to reference/hardware acceleration on 64-bit CPU

ECDSA (Elliptic Curve)

Modern and efficient signature algorithms using elliptic curve cryptography. Suitable for high-performance modern systems.

EdDSA (Edwards-curve)

High-performance and secure modern signature algorithm. Fast, secure default choice.

RSA

Classic and widely used asymmetric encryption-based signature algorithm. RSA-PSS is modern, RSA-PKCS#1 v1.5 is legacy (compatibility only).

Related Standards
  • FIPS PUB 186-4
  • RFC 8032
  • RFC 8017
  • ISO/IEC 14888-3