Ed25519

wikipedia:Ed25519 is the EdDSA signature scheme using SHA-512 (SHA-2) and Curve25519.

OpenSSH

• OpenSSH 8.5 March, 2021 changes the first-preference signature algorithm from ECDSA to ED25519.

• OpenSSH 6.8: March 18, 2015
  • Added new [email protected] extension to facilitate public key discovery and rotation for trusted hosts (for transition from DSA to Ed25519 public host keys)
  • AuthenticationMethods=publickey,publickey to require that users authenticate using two different public keys

Key management

Key generation:

• ssh-keygen -t ed25519
• ssh-keygen -t ed25519 -f your_new_ed25519_key

ssh-keygen -e -m PEM -f private_key_in_ed25519_format
do_convert_to_pem: unsupported key type ED25519

Related terms

• ssh-ed25519 in .authorized_keys config file
• ssh-copy-id
• EdDSA
• djb
• Key size
• aws ec2 create-key-pair

See also

• OpenSSH (changelog): /etc/ssh/sshd_config | /etc/ssh/ssh_config | ~/.ssh/ | openSSL | sshd logs | sftp | scp | authorized_keys | ssh-keygen | ssh-keyscan | ssh-add | ssh-agent | ssh | Ssh -O stop | ssh-copy-id | CheckHostIP | UseKeychain, OpenSSF
• Public-key cryptography: RSA, DSA, ECDSA, EdDSA (Ed25519), AES, RSA Conference, hash, pkeyutl, Signature, key length, Easyrsa, OAEP, Ron Rivest, Adi Shamir, Leonard Adleman

Murenin, Constantine A. (2015-02-01). Soulskill (ed.). "OpenSSH Will Feature Key Discovery and Rotation For Easier Switching To Ed25519". Slashdot. Retrieved 2015-02-01.

https://lwn.net/Articles/637147/