standard specifies additional key types, including one based on Ed25519.
Use of U2F security keys does not automatically imply multi-factor
-authentication. From sshd’s perspective, a security key constitutes a
+authentication. From sshd's perspective, a security key constitutes a
single factor of authentication, even if protected by a PIN or biometric
authentication. To enable multi-factor authentication in ssh, please
refer to the AuthenticationMethods option in sshd_config(5).