Curve25599 is a very fast elliptic-curve-Diffie-Hellmann function that was proposed by Daniel J. Bernstein in his paper â¦ I recently implemented the elliptic-curve algorithms X25519 (RFC 7748) and Ed25519 (RFC 8032) for TrustonicÊ¼s crypto library, in portable C. These algorithms provide primitives for key agreement and digital signatures respectively. Full html documentation is available here. Ed25519 is a deterministic signature scheme using curve25519 by Daniel J. Bernstein, Niels Duif, Tanja Lange, Peter Schwabe and Bo-Yin Yang. Key size comparison: symmetric AES, asymmetric RSA and elliptic curve The importance of using the right key size (e.g. Description. ssh-keygen -t ed25519 -C "