Ok, so I think I've worked out what is going on with "iGrid":
Essentially the PAW box runs both PAW and Router services (I'll call this PAW-Router).
The PAW service transceives aircraft traffic info and provides a web interface
The PAW-Router service manages subnet 192.168.1.*. It identifies itself as 192.168.1.1. The PAW service is bound to this IP address.
It has a Wifi network of SSID "PilotAware_<mac-address>" and assigns IP addresses via DHCP
However, PAW can also join an upstream network (typically a mobile phone running a hotspot wifi such as "Johns Iphone") which will assign it a DHCP address, such as 192.168.214.116 on its subnet (e.g. 192.168.214.*) . This will be used as the gateway (to get to the Internet).
The mobile phone will have its own IP address, e.g. 10.60.200.76 on the network provider's subnet.
A device (such as a tablet) can now join the "PilotAware..." network and will receive an address 192.168.1.2+
Skydemon running on this device will look for the PAW component on address 192.168.1.1
A device could attach to the mobile phone's hotspot wifi "Johns Iphone" and that device, or the phone itself, could run Skydemon and the phone will route requests for 192.168.1.1 back to the PAW-Router which will pass on to the PAW webservice.
Essentially PAW becomes a local network that, when connected to a hotspot, provides devices that connect access to the PAW webservice and upstream to the internet. One could connect one or more devices to receive traffic information but also a passenger could connect to the PAW Wifi network and use it to access the internet.
Phew.
It's a neat, if complex, solution.
Questions:
Can you plug a USB GSM dongle into the PAW box for upstream internet access instead of joining a mobile phone's hotspot?
Can you connect the PAW box using an ethernet cable to an upstream network? So one wifi dongle and one wired connection (to the upstream network)?
Can you connect a wired consuming device to the PAW network? One or two wifi dongles and the wired connection will provide an address on the local PAW network?
What does the "Router" setting actually do?
Looking at the network info available it would be useful to have other info on there as well as IP... subnet... gateway... even dns... so one can see what's happening.. I've got mine currently with one wireless dongle and an ethernet cable into my home router. I can access "paw.local" over my network and I can have a device that can connect to PAW's Wifi. However my local network's subnet is 192.168.1.*, and my router is 192.168.1.1 and so conflicts with the PAW's network. So whilst a device can connect on the PAW wifi.. when it tries to access 192.168.1.1 it can't...
It's a shame PAW didn't originally use, for example, 192.168.201.* for its subnet. Then there would never be conflict with home networks when one is fiddling at home.. doesn't really matter in real life but would have been good.
Perhaps even advanced settings - for each network interface (ethernet, wifi dongle, GSM dongle - which I don't think is supported) ability to configure usage..
