Internet Connection Sharing

Ok so you've got your PC connected to the Internet over cable or xDSL or any kind of technology. When you buy a new computer and you want Internet on both of them it always comes to the same problem: how do i share my Internet connection? Well there are two major possibilities: to buy a router or to use the first PC as a server for the other. Either way, the main idea is that you need a device that knows to route packets from one network to another, and a basic switch cannot do this. A. Internet Connection Sharing using a router The first thing you should consider is your connection type when buying a router. Some connections (like ADSL) work on protocols that require some kind of authentication (eg PPPoE - Point to Point Protocol over Ethernet). This assumes that the device that connects to the Internet Service Provider must know to work with something like that. Most of the routers available have this options, but better safe then sorry so ask before acquiring it. The router has two interfaces that need to be configured. One is the WAN (Wide Area Network - links you to the Internet) and one is the LAN (Local Area Network - links your PCs). The WAN must be configured (don't worry, it's all done with a web-interface wizard in easy steps) with your Internet settings (like IP address, subnet, gateway, DNS servers, and possible authentication issues. After doing this, your device is connected to the Internet. Now you have to connect the two PCs to the LAN side of the router. You'll need two straight through cables (PC1 and PC2 to router) that usually come in the router's box. This also works as a switch, so you'll be able to share files between them. I strongly recommend to use the DHCP (Dynamic Host Configuration Protocol) available on almost any router to automatically assign addresses to local computers. After doing this, go to your PCs and select in your Network Connections the active connection and then right click it - Properties - TCP/IP and be sure it's selected to get it's IP address and settings automatically. You should now access the Internet from both computers with no problem. If the router doesn't connect, it could be a restriction based on MAC addresses (network card's hardware address). If you think this is the problem, contact your Internet Service Provider to resolve the issue. B. Internet Connection Sharing using a computer Firstly, you need two network cards on the computer. It will work exactly like the router with a WAN interface and a LAN interface. Now the easiest way available if you are using Windows XP is to go to Network Connections and select the "Set up a home or small office network" link from the left panel. This will open a wizard that will guide you in completing the task. If you don't want to use the wizard, you just need to configure the ICS option. First go to Network Connections and select the two connections, right click and select the bridge option. This will make the two cards aware of each other. Now right click the connection to the Internet and select Properties. On the opened box, uncheck the Client for Microsoft Networks and File and Printer Sharing for Microsoft Networks protocols because it's a security risk. Now click the Advanced tab and select the Allow other network users to connect through this computer's Internet connection. It's a good idea to enable the first option too if you don't have a firewall installed on the machine. Now all the computers in the network should access the server's Internet connection. Note that the server must be powered on to share the Internet connection.