$ ssh-keygen -t rsa -b 4096 -f ~/.ssh/id_rsa_iso2
>Generating public/private rsa key pair.
>Enter passphrase (empty for no passphrase):
>Enter same passphrase again:
>Your identification has been saved in /home/akira/.ssh/id_rsa_iso2.
>Your public key has been saved in /home/akira/.ssh/id_rsa_iso2.pub.