Network configuration with Wi-Fi router

Outlined below is my home network configuration. I got four personal computers ( 2 desktops and 2 laptops). I also have a Wi-Fi router(a/g) which can be used as a switch as well. Below shows the network configuration.

One of the PCs act as a gateway to the internet via a dial-up connection, dial-up? you might say, well that's what I have right now. It would have been really better if I can use my Wi-Fi router to connect to the internet but I believe its not going to happen anytime soon. Wi-Fi router also acts as a DHCP server which provides private IP address starting from 192.168.1.100. The Wi-Fi router which is an AirLink 101 model AR315W (802.11g Wireless router) was setup to be wired switch as well as an AP for wireless nodes.

Setting up the Wi-Fi wireless router
The AR315W can be configured using any recent web browser on address 192.168.1.1. The default username and password is admin/admin. With the rest set to default, for my network needs, I have to change "Wireless" and "Administration|PC Database".

I got two Windows XP SP2 and two Windows XP Home Edition with file sharing enabled by default. To increase security, at least for casual user, I need to secure my network. For AR315W, this can be accomplished by going through the "Wireless" section of the web-based configuration tool supplied with the product. In the event that I may need to reconfigure my router, I might document all the steps that I have taken here. But for now, I would think that it is enough to say that to secure the network, again atleast for the casual user, one needs to enable WEP encryption.

As described above, the router was only used for providing wireless and wired connection but not connected directly to the internet. To be able to access internet "Administration|PC Database" needs to be modified to fix the IP address of the computer that is connected to the internet. This can be easily accomplished by accessing the "Advanced Administration" within the screens provided by "Administration | PC Database".

With the internal network IP address of the computer connected to the net fixed, we need to get the DNS servers provided by the ISP provider to our router. This is necessary since, agian, our router is not directly connected to the internet. To change/update the routers DNS server list, access "Administration | Options". Under the Backup DNS section, supply the IP addresses of the DNS servers. Under Windows NT based OS, the IP addresses of the DNS server provided by the ISP to the computer connected to the internet can be viewed by using "ipconfig all" in the console.

With everything setup in the router, one more step needs to be taken on the client computers. We need to change the default gateway of these computers, do note except for the computer that is directly connected to the internet. The reason this is necessary is that there is no way that I know off to change the default gateway of AR315W router. For the uninitiated, default gateway can be changed in Control Panel | Network Connectsions. Invoke context menu for the connection the router and then Properties. In General tab, select on Internet Protocol(TCP/IP) then hit on Properties. Under Internet Protocol(TCP/IP) Properties window, click on Advanced button. In Advanced TCP/IP Settings, IP Settings tab, group Default gateways hit on Add then enter the IP address of the machine connected to the internet. In my case, the IP would be 192.168.1.101.

With all this set, all the computers in the network should be able to talk to each other and connect to the internet as well.