Port Mapping for Airport.
1) Go to your finder and type in Airport in the search and find your Airport Utility program.
2) If it prompts you to be configured manually or not select Manual
3) Find the Advanced Tab at the top and select it
4) Choose the Port Mapping option here, or depending the “IPV6Firewall” (You will have one or the other)
When you try to access your camera over the internet when you are away from your local network, the external IP address to your router will be used. But, you need to be able to direct the incoming connection straight to your camera. This is particularly important when you want to address multiple cameras. You will add a special port number to the external IP address. Port mapping tells the router which device is accessed by which port. To start adding ports you must click the little “+” sign at the bottom and you will see something similar to the screen below.
In the dialog box that comes up, leave the ‘Choose a service” dropdown menu untouched. Enter the Private IP address for the camera, as it appears in IP Scanner. Assign a port number to the camera, that isn’t being used by anything else like 81, 82, 83, etc. (see Well known TCP and UDP ports used by Apple software products: http://support.apple.com/kb/TS1629?viewlocale=en_US).
Be sure to click on the Update button after making these changes to upload them to your Airport.
Now go back to your cameras interface and under Basic Network Settings verify that the “Http Port” is the same as the port that you forwarded.
You should be just about done by now, you can try out your routers external IP Address which can be found on the router (or by googling “whatsmyip”) and at the end of it put the port of your camera for example port 81 (Example:18.104.22.168:81). And you should be done.
If you are having any trouble check out the detailed guide for PC’s as the process is very similar, yet the PC version is far more detailed and it may be able to help you.