To get rid of password authentication, use DSA keys. Follow these steps:

Create the public/private key pair, they are placed in “~/.ssh”

usuario1@sshclient:~$ ssh-keygen -t dsa

Copy the public key to the other host:

usuario1@sshclient:~$ cat ~/.ssh/id_dsa.pub | ssh usuario2@sshserver "cat >> .ssh/authorized_keys"

Change permissions:

usuario1@sshclient:~$ ssh usuario2@sshserver chmod 600 .ssh/authorized_keys