Internet connection sharing (ICS)

Internet Connection Sharing( ICS) is specially designed for end users who want to access the Internet with all personalcomputers(PCs) of a small home network via a single access point. It is a software that runs under Windows 95/98/ NT/2000, works as a gateway with routing functions, and is installed on the central personal computer.

The ICS software developed by Microsoft is installed on the central computer, which forms the server for the local area network( LAN) and acts as a gateway between the Internet and the local network, where it provides routing. Only the server is connected to the Internet via modem, ISDN or ADSL.

When operating ICS, the local network must run the same protocol as the Internet, i.e. TCP/ IP. For ICS special IP addresses of class C have to be provided: 192.168.0.x. These IP addresses are especially interesting for small companies. They are not assigned any more anyway and therefore not routed. If the IP address 192.168.0.1 is assigned to the gateway, then the following IP addresses can be assigned to the connected clients: 192.168.0.2, and so on. The gateway itself has a different IP address on the Internet side and transfers the requests from the Internet to the IP address of the corresponding client using Network Address Translation( NAT) with an assignment table.