- Used to verify the authenticity and integrity of digital messages or documents.
- Employ a mathematical algorithm and a pair of keys (private and public):
- Private key: Used to create the signature.
- Public key: Used to verify the signature.
Key features:
- Uses twisted Edwards curves, known for efficiency and security.
- Nonces are not required, reducing the risk of implementation errors.
- Resistant to timing attacks and other side-channel attacks.
- Generates deterministic signatures (same message and key always yield the same signature).
- Commonly used with Curve25519, a popular and efficient elliptic curve.
- Examples: SSH (Secure Shell), TLS 1.3 (Transport Layer Security), Tor, Signal, and other security-critical applications.
Key features:
- Based on elliptic curves in Weierstrass form.
- Requires random nonce generation for each signature, potentially leading to implementation vulnerabilities if not done properly.
- Generates non-deterministic signatures (same message and key can produce different signatures).
- Commonly used with the secp256k1 curve, especially in cryptocurrencies.
- Examples: Bitcoin, Ethereum, and other cryptocurrencies, as well as TLS, digital certificates, and smart contracts.
- Security: EdDSA generally offers a higher level of security due to its resistance to side-channel attacks and deterministic signature generation.
- Performance: EdDSA is often faster than ECDSA, especially for signature generation.
- Compatibility: ECDSA is more widely adopted in some areas, particularly in cryptocurrencies.
- Specific requirements: Consider the specific needs of your application when making a choice.