There are two ways to connect your home or small office network to the Internet. You can use a residential gateway, or use Internet Connection Sharing (ICS).
Residential gateway
A residential gateway is a hardware device that connects a home or small office network to the Internet. This device is sometimes called an Internet gateway device, a router, a base station, or an access point. The residential gateway lets you share a DSL or cable modem Internet connection with all of the computers on your network.
The advantages of using a residential gateway are:
The gateway looks like a computer on the Internet, which hides the real computers on your network when you are on the Internet.
The gateway shares one Internet connection with all the computers on your network.
One computer does not have to be turned on all the time to provide Internet connectivity.
You can use the UPnP framework to control your Internet connection from anywhere in your home or small office.
The disadvantage of using a residential gateway is that the hardware is more expensive.
Using Internet Connection Sharing
If you do not want to buy a residential gateway device, you can use a configuration like this illustration of an Ethernet network. You can create a home or small office network using this configuration with a home phoneline network adapter (HPNA) or wireless network adapters. In this configuration, one computer is the ICS host computer and shares its Internet connection. Internet communications to and from the computers in your network go through the ICS host computer.
The advantage of this configuration is that sharing one Internet connection with all the computers on your network can cut the cost of connecting to the Internet.
The disadvantage of this configuration is that the host computer must be turned on at all times so that the other computers can access the Internet.