Please note that the internal password security of the N9 like the N900 is very very weak !

Passwords are stored in /etc/passwd with a very simple "Traditional DES" encryption which makes cracking password from the N9 a matter of minutes to hours.

So please don't use passwords but use ssh keys like described earlier in this thread and then change your /etc/ssh/sshd_config to read:

Even if the password storage was not so weak I would still recommend this, since your likely to connect to many foreign networks.