The earlier post (since locked) got me to thinking, how do I make sure my hub isn't exposed to the internet? I don't have it on a vpn or anything, it's just connected to my AT&T modem/ router (that in itself has been bothering me lately, but that's another topic). So can anyone offer any suggestions on how to make sure my hub isn't exposed, and to keep it that way?
Most likely your hub gets its IP address assigned from your router in the range of 192.168.0.0 - 192.168.255.255, and if you are doing it right, you actually have told your router to reserve that IP for exclusive use of the MAC address (globally unique identifier assigned to the hub's ethernet adapter) so it will always get the same one.
Addresses in that range are non-routable outside of the scope of your router. This allows everyone to have networks in this range without conflict with anyone else's local LAN. It also means that things outside of your own network cannot reach your hub because those addresses aren't unique in the world.
Port forwarding means that you tell your router to forward traffic for its own IP address, which is NOT in this range externally to a local, otherwise non-routable, IP address. So as long as your router is doing what it is supposed to do, and it is giving your hub a 192.168.x.x IP address, and you haven't set up port forwarding, your hub is unreachable from the rest of the world.
Hope that helps.
Hum, I don't think I ever told my router to do anything, one way or the other , I just plugged it in and started adding devices. I didn't really give it much if any thought.
Well, as long as your router and hub stay active, the hub may from time to time ask for an IP address but there will be a tendency for the router to keep handing it the same one. However, to make sure this happens even if, say, you unplugged your hub for a few days, you should make a reservation. How you do that would be documented in your router's instructions (google your router's brand and model along with "DHCP reservation").
Then your hub is very likely not exposed to the internet for the reasons @HAL9000 explained. The way home internet modem/router devices are configured, you’d have to take some affirmative step in almost all cases to expose your hub in some way.
I would second his suggestion re: assigning a local reserved DHCP address for your hub.