If you're working with a Raspberry Pi, you can attach a Wi-Fi dongle (like this one)
to get wireless access on the device.
To connect to a WPA authenticated wireless network:
> set_network 0
> set_network 0 ssid "<ssid>"
> set_network 0 psk "<password>"
> enable_network 0
# (Ctrl+C to exit)
Note: you need the double quotes.