I am semi-tech savvy but, about the security concern with my Wi-Fi network, wouldn't someone need to know my network name and password to get in?
Also want to thank Anthony for a fantastic writeup.
DD - from what I can infer - you access the app via a URL. That URL is an IP address/Port Combo.
When I'm on WiFi, my internal boxes are 192.168.x.x.
One of those boxes is running my webserver and it's also 209.177.x.x.
I'd guess that if you never want to access your AHP remotely -- only use it when you're at home and connected via WiFi to your own network, then sure, set up the embedded webserver to be your internal address.
When instructions usually talk about opening up ports in your firewall, you're then exposing an internal host to the public internet. Hence the security concerns.
In my house there are precious few ports open to the internet.