Setting up a shared internet connection in Windows XP

If you have one computer connected to the internet (from now on called the "server"), and another connected to that computer (from now on called the "client") via a wireless connection you may wish to have the client access the internet through the server. The normal way of doing this is to use Windows built in ICS, however if you dont wish to use this (eg it doesnt work or doesnt provide you with enough control over the connection) you may wish to manually set up a proxy server. This tutorial tells you how.

You will need..

· One computer connected to the internet, with a Wireless card
· One (or more) computers with wireless cards
· FreeProxy (see below) installed on the server pc
· Windows XP

Note: You do not need a router for this configuration, meaning you can just get two ten pound wireless c ards for this to work. The down side of not using a router is that the server pc has to be running whenever you want to access the internet through a client. Also note that the following screenshots and instructions are for Windows XP SP2, though the instructions should be simliar for any version of Windows XP.

Implementation

Firstly you need to make sure that the two computers have their wireless cards installed, and that they are connected to each other. When they are both connected there should have a small icon visible on the taskbar like so:  If they dont seem to be connected to each other then see the troubleshooting section below.

Setting up the server

Instead of using Windows built in ICS, you can set up a proxy server manually on the server. To do this we're going to use a proxy server called "Fr eeProxy" - you can download it for free here or here. Install FreeProxy then choose "Free Proxy Control Centre" from the start menu. Once FreeProxy is running click the ports option, then fill in the protocol as "HTTP Proxy", any name and the local binding as "Wireless" (you may wish to save setting the local binding until later to make sure the connection works). You should also select "Any Ip Address"

Now click "Done" then Start/Stop. Now press start for Console Mode to test whats happening, and Start under service mode so the service shold run automatically.

Assigning IPs Manually

Whilst technically you dont have to manually assign IP addresses to get this to work , unless you set them for both computers the Wireless connect ion may be unreliable. To do so: Open up "Network Connections" either from the start menu (As below) or from the control panel. 

Click internet TCP/IP then properties.

 You can choose the IP you want, though the IP range 169.x.x.x is reserved for local networks, and the IPs should be unique. For example, choose 169.254.1.1 for the server and 169.254.1.2 for the client. If you are also using ICS (internet connection sharing) then you should select something in the range 192.168.x.x

Setting the proxy

Now you need to tell Internet Explorer/Firefox to use the proxy server. Set the ip as the of the server pc, and the port as 8080 (unless you set it differently).

To do this:

· Under internet explorer Press Tools,Internet Options, Connections Lan Settings

. 

· Under firerfox Click Tools,Internet Options,Connection Settings, then select manual configuration and fill in the details (for HTTP proxy).

Troubleshooting

Checking the connection using ping

If you want, you can check that the connection between the two computers is now working using the ping command. · Open the command prompt by opening the start menu, clicking run, typing "command", then clicking ok. · Now type "ping IP" -where IP is the ip of the other computer · If you get some kind of reply, then the connection works. If you get "Destination Host Unreachable" then the connection isnt working and you should see the troubleshooting section below.

Checking and repairing the connection

Open up the wireless connection, either by double clicking the wireless icon on the bottom right of the taskbar, or by going to "Network Connections" (on the start menu/ under My Computer) then double clicking. You should be presented with something like the image below:

If the amount of bytes received is zero then there is a problem. Try moving the two computers closer together, and make sure that you have manually set the ips (see above). Click support, and the following should come up:

The ip should be visisble, and there is a repair button. Clicking it can solve some problems.

Creating a w ireless connection

If the above dont seem to work t! hen the wireless connection may not be set up correctly. See step 4 on the tutorial here for more information. Essentially, you can either create a new connection through the built in windows software of the software that came with your wireless card. Create a wireless connection on one computer, and connect to it on the other. Try without using encryption to get the connection working, then go back and enable it once it is.

Firewalls

Firewalls can get in the way of proxy servers. If you are having trouble try turning them off whilst setting up the network, then re-enabling them once it is working.

By Chris Doman