Initially you should have router with OpenWRT firmware with OpenVPN client enabled. The main page of the firmware is http://openwrt.org Router, flashed with OpenWRT firmware image, initially accept connection only by telnet, so you should connect to it by telnet to the IP 192.168.1.1 and change root password with command "passwd". After this command it accepts connection via ssh. By default openvpn isn't included in the firmware image, so you should install it by use of opkg:   # opkg u