Hey I found out that this Wi-fi network named BT-WiFi uses people’s networks which optted in. Apparently it shares connections. How would that work?
so if your BT wifi is down because of IP reset, DDoS attack, whatever, would your BT Wi-fi hotspot still be up?
No, if you have no broadband connection, your BT WiFi signal obviously can't connect to the internet either. It uses the same physical broadband line as your own wifi, just a totally separate subnet.
As has been said, BTWifi uses your broadband connection. If your connection goes down so does BTWifi . See links for further information about BTWifi