ssh-keygen -t dsa

Will generate a pair of public-private key (with type DSA) inside ~/.ssh/. Defaults are:

id_dsa

and

id_dsa.pub

The public key can be tranfered to other host with running sshd (ssh server). Default authorization key file used by sshd is ~/.ssh/authorized_keys (this can be configured from /etc/ssh/sshd_config). Append the generated id_dsa.pub to this file in remote host:

$ cat id_dsa.pub >> authorized_keys

My host with private key id_dsa can now ssh to remote host containing my public key in its authorized_keys file.