9. Routing

Some routers have non-NAT routing features. This means that instead of manipulating data so that many computers can share a single IP address, the router can properly direct traffic among all computers on networks that use more than one range of IP addresses. One of the key functions that's performed is making sure that all computers know the IP addresses of the various network gateways and DNS servers and where to send data that's intended for computers that are on different subnets. Note that this feature does not solve the problem of getting Microsoft File and Printer sharing to work so that all machines on all subnets can see and communicate with each other. That requires a Domain controller, which you get by either adding a Microsoft-based server or 'nix machine running SAMBA.

There are two kinds of additional routing features. Static routing requires that you manually enter subnet information into the router. Dynamic routing uses RIP (Routing Information Protocol) to allow RIP-aware devices to share network routing information automatically.

If this explanation isn't that clear to you, don't worry too much. If your network were complicated enough to require these functions, you probably already know more about them than we do!