Added instructions for streaming over the internet.

Setup-Guide.md

@@ -1,6 +1,7 @@
 In this guide: 
 * [Prerequisites](https://github.com/moonlight-stream/moonlight-android/wiki/Setup-Guide#prerequisites)
 * [Quick Setup Instructions](https://github.com/moonlight-stream/moonlight-android/wiki/Setup-Guide#quick-setup-instructions)
+* [Streaming over the Internet](https://github.com/moonlight-stream/moonlight-android/wiki/Setup-Guide#streaming over-the-internet)
 
 ***
 
@@ -30,12 +31,17 @@ Use SixAxis in "Native Gamepad" mode. The default button mapping needs to be adj
 
 Using an external mouse as a relative input on Android requires a rooted device. If you want to use an external mouse on your rooted device, you should download "Moonlight for Rooted Devices" on the Play Store or app-root-release.apk from releases.
 
-##Quick Setup Instructions:
+##Quick Setup Instructions
 1. Make sure GeForce Experience is installed, updated, and that you've scanned for games.
 2. In most cases, your PC will show up automatically in the PC list. Click the entry in the PC list to start pairing.
 3. On your PC, enter the PIN displayed on the Android device and accept the pairing dialog.
 4. Choose your PC in the PC list and the app list will be displayed where you can select a game to stream.
 
+##Streaming over the Internet
+NVIDIA has disabled UPnP support in GFE 2.4.1, so it is necessary to forward ports manually if you're behind a router. Forwarding ports is only required to stream from outside your network. The following ports must be forwarded for streaming to work:
+* TCP 35043, 47984, 47989, 47995, 47996, 48010
+* UDP 47998, 47999, 48000
+
 ***
 
 This page is under construction