Dedicated NAT/Firewall box

This article explains how to set up a home network using a dedicated NAT/Firewall box. In essence the features of a separate box are about the same as what the software solutions provide. This is described in the article about "Software NAT, Firewall or Proxy?", that also covers the two reasons (sharing one IP address and providing security) for having these functions.

This is what you need: Cable or DSL Modem,
a NAT/Firewall box, a few PC's with ethernet cards
and enough ethernet cables to tie it all together.
The printer is optional.

The links section has a fairly comprehensive list of specific products that are more or less targeted at the SOHO, home business and tele-commuter markets. Look under "Internet Sharing > Hardware".

My recommendation is the Linksys cable router box - read my review here.

A clear advantage of the separate box approach over running the NAT/Firewall functions as software on a gateway machine is that no gateway machine needs to be on in order to access the internet from the other machines. Only the NAT/Firewall box and the cable modem needs to be on.

If the printer is connected to one of the client PC's as in the above diagram, this somehow slashes the advantage. To be able to share the printer, the PC with the printer connected will have to be on. The way around this problem is to add a printer-server box as shown below.

This is what you need: Cable or DSL Modem,
a NAT/Firewall box, a printer server box,
a few PC's with ethernet cards and enough
ethernet cables to tie it all together.

This configuration allows you to turn any client PC on the local LAN on or off as needed. The boxes that you should leave on always are the Cable/DSL Modem, the printer, the NAT/Firewall box and the Printer Server box.

Notice that some high-end printers accepts a LAN interface card, that functions as the printer server box. The cost of the internal solution may very well be well above the cost of a separate printer server box - but if cost is not an issue, that is the preferable solution.

See also the other articles about internet sharing.