Introduction A lot of people dont know that if you run Windows XP or Windows Vista it is possible to build your own wireless network at home or office without using a wireless broadband router or a wireless access point, saving some bucks. In this tutorial we will show you step-by-step how to build this kind of wireless network, also known as ad-hoc. More and more people are willing to assemble their own wireless network. With a wireless network set at your home or office, you will be able to share files, use the printer and access the Internet without the need of connecting a network cable to your computers. This is great if you have desktop computers located in places where is hard to install a network cable or if you want to have the freedom to access your network and the Internet using your laptop anywhere inside your home or office: you can carry your laptop from your bedroom or office to your living room and it will still be connected with no cables attached. Of course we are talking about laptops with wireless network capability all new laptops have this feature. If you are using desktops or laptops without wireless capability, you will need first to buy a wireless network card for each computer you want to connect to your network and to the Internet wirelessly. In order to build your own wireless network you will need the following: A broadband Internet connection; A wireless network card installed on each computer that you want to connect to your wireless network; A wireless broadband router (optional). Usually a piece of hardware called wireless broadband router or access point is required. In this tutorial we will teach you how to setup a wireless network without this device, allowing you to save some bucks. However, you need to know beforehand what are the disadvantages of not having a wireless router: The only encryption scheme supported in Windows XP is WEP, which is not secure: a hacker with the right knowledge can have access to your network. Thus if you are building an ad-hoc network the way we are describing the host computer (the one with the Internet connection) must be running Windows Vista or greater so you can enable WPA2, which is a secure encryption system. The client computers can be running Windows XP, this requirement is only for the host computer. The computer that has the broadband Internet connection will need to be always turned on. If you turn it off the other computers will lose their connection to the Internet. Your network will be less safe, as broadband routers integrate a hardware-based firewall. Your network speed will be limited to 11 Mbps, even if you only use 54 Mbps or faster cards on your network. You can also configure an ad-hoc network even if you already have a broadband router without wireless capability. If this is your case, please forget about the second item listed above, but the other items will still be true. Also, there is something very important if you have a broadband router already installed on your network: you will need to change the IP address range of your network if it is configured to use the 192.168.0.x range to 192.168.1.x because the Windows Internet sharing service also uses the 192.168.0.x range and you will have conflicting IP addresses on your network. This configuration is done by entering the routers setup program (usually by opening http://192.168.0.1 from any computer connected to it).