Window’s network sharing

On the university network here, we’re only allowed to plug one computer into the network points in our rooms. If you try plug a hub in, or bridge connections to other computers the network detects this and blocks all the computers on your network point until the problem is rectified. I’m sure the varsity has several reasons for doing this, one of which being that they assign every computer a unique IP address, and there list of addresses is limited, as well as it being a way to keep track of what computer’s are on the network, as one is required to register your computer’s mac address, so they can assign the same IP address.

In any case, this makes life difficult for people with more than one computer, or with a computer and a console. One way to get around this is to setup a NAT. You plug your registered computer into the network, and then plug other devices into that computer. By setting it up correctly, those devices are hidden from the network, and all traffic is just routed via your main computer. I made use of this last year, but this year invested in a MikroTik Router Board 750 which effectively does the same thing.

In any case, from Windows, the easiest way to do NATing is to make use of Windows built in Network Sharing. It’s a fairly straightforward setup. All that’s required is two network cards. And you can plug a hub into the 2nd network card if you require more devices. I recently put together a step by step guide to setting it up which can be downloaded at the bottom of this page.

It gives instructions for setting up Windows Network Sharing in both Windows 7 and Windows XP. One example is with sharing an internet connection from a WiFi network to a LAN network, and the other is LAN to LAN setup.

If you are wanting to setup a wireless AP, that is use a WiFi card to share a network connection, I advise making use of a program such as Connectify, which I have used on several occasions to great success. It allows one to easily setup a wireless AP, and automatically allows password encryption.

You can download my step by step guide here (592 kB).