what happens internally in a router when lan is configured?

How do I set up a private LAN in my dorm room if the university issues publicly visible IP addresses for all devices connected to its network?

• I just moved into university housing and the most irritating thing about their network is that their internal/external IP addresses are the same i.e., the LAN IP itself is publicly visible. I have multiple devices and I share a lot of content among them (tablets, Laptops/PCs etc.,) Ex. Streaming from my desktop to my tablet etc., If I have each device on the university network I can't do any kind of remote screen sharing or streaming or any sharing in general. I was thinking if it's possible to set up my own private LAN/network in my room but don't know how to go about it. I have a router that is connected to the ethernet port in my room. However, if I try connecting to the router's Channel/SSID nothing really happens. I'm redirected to an authorization page which asks me to restart the machine(s) after entering valid credentials. This keeps happening no matter what. I know my university stores the MAC addresses of the devices that connect to their network and am not sure if that's the problem. I've cloned the MAC address to the router but it doesn't seem to work either. I've also contacted the IT staff of the university and they said that it's not "allowed" although I'm not sure how/why? I was told discreetly by one staff member that some folks had done this and he didn't see why it was a problem. However, I'm surprised it's this tricky! I'm sure it's not rocket science and should be fairly easy to pull off but doesn't seem like it. How should I set up my own private LAN with my router and devices given this scenario?

• Answer:

  It sounds like you have a standard Cable Modem-ready router in that it's WAN port is an Ethernet port which you are connecting to the University network. My first thought here is what are you login settings? There are two methods of establishing a connection via these routers normally: PPPoE (PPP over Ethernet) or DHCP. Your commend about entering credentials and restarting the machines could suggest it's configured to operate via PPPoE. Have you configured it to work with DHCP on the WAN port?