In my previous post I was talking about how to configure your Pi to be able connect to it with Remote Desktop Connection. But this was only on a local network. What if you want to be world wide?
Open a web browser like Chrome and write 192.168.1.1 or 192.168.0.1 to connect to your router.
Search in the options and you should find NAT or Port Forwarding in the Advanced Settings or Expert Mode (depending on your router’s brand).
If your Raspberry Pi’s IP address is 192.168.0.2 then enter this address and for the Port 3389 for both TCP and UDP protocols.
So now if you take your laptop outside of your home network (with your phone’s data connection for example) the you should be able to reach your Pi with Remote Desktop Connection from the outside world.
To get your external address just ask it to Google: “What is my ip”, and enter this address into the RDP Client.
But you have to know that your Internet provider change your external IP address sometimes everyday. There is a free and easy solution for that. See my post about the Dynamic DNS.