ED25519

Ed25519 is an EdDSA signature scheme that uses Edwards curve equivalent of Curve25519 for digital signatures.
The "25519" in Ed25519 and Curve25519 refers to the prime number ( $2^{255} - 19$ ), which is a fundamental part of the curve's definition. Ed25519 uses 256-bit private keys and produces 256-bit public keys.
- therefore, cryptographic-length of Ed25519 is 256 bits, i.e. $2^{256}$ of possible private keys.

cryptographic algorithm: use ED25519. No <3k RSA, no NIST

Therefore, we could say 256-bit ED25519 key has the security level the same as 128-bit symmetric-cryptography key