Simple summary:

challenge-response authentication.

Generate your ssh-keys with <ssh-keygen -d> for ssh2.

You will have the files $HOME/.ssh/id_dsa.pub and $HOME/.ssh/id_dsa.

The id_dsa.pub - file is your public key. Copy that file to the target
+ to
$HOME/.ssh/machinename.pub and do a
"cd .ssh; cat machinename.pub >>authorized_keys".

Now you should be able to connect to the target
machine via ssh without using passwords.
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