Can a wireless network span floors in a house?

A wireless base station is unquestionably your best solution in this situation. We have a split-level house that has four different floors, and our cable modem connection comes into the basement where it's connected to a broadband router, which is then hooked up to an 802.11b wireless base station. With that in place, we can connect wirelessly anywhere in the house and yard.

Even better, it offers lots of protection for your computers and home network too, because the router is what has the external-visible internet (IP) address assigned by the DSL or cable company, while your individual computers are given different addresses through the magic of what network types call Network Address Translation.

Modern wireless base stations also serve as routers too, so you can easily buy one $50 unit and have it set up so that it's your main interface with the DSL modem, that the downstairs computer hooks up directly to it via Ethernet (you might as well, they'll probably be sitting on top of each other), and the upstairs computer works completely via wireless.

For example, Amazon is offering a Linksys Wireless "G" Router which would work perfectly for you, and it's less than $50. There are other choices from different vendors too, if you have a preference.

Once you do set this up, i strongly suggest that you at least enable some basic password on your wireless network. It's not necessarily 100% secure, but it will prevent your neighbors tapping into your local network and borrowing your bandwidth (and remember, if they do that, they're also on your "local network" when they decide to browse your computers to see what files you've left findable).

I've found setting up wireless networks with both cable and DSL to be quite straightforward. I bet you'll have no problems with your own network configuration and will be pleased and delighted when it's all up and running.