It uses ssh(secure shell) protocol(encrypt communication between client and remote machine), so you can safely execute command. In addition, since the ssh command can use key authentication using secret key / public key, you can further improve security by using them.
ssh -i /path/to/key
Specify the private key file(identity file). In the initial setting, SSH version 1 is /.ssh/identity, ssh version 2 is /.ssh/id_rsa and /.ssh/id_dsa
