Using a computer as an access point

Ok so heres my situation: In my house we have several computers all networked together: two windows PCs and my Macbook pro. My mac and my desktop (XP and ubuntu dual booted) are both wireless up in my room. So what Im curious about is if it is possible to use my desktop in either ubuntu or windows as a wireless access point and send the signal to a switch which will sit on my desk so I can plug in other computers to share files, internet etc (Ive recently started doing a little bit of tech work and this would be the main use of this set-up). Im was thinking of how to do it and got stumped because Im not sure how I would send the signal received from the wireless PCI card out through the ethernet and to the switch. Any ideas?

 

Are you asking to use you desktop as a hub? I am not really sure what you are asking.

 

I'm not 100% sure but could you use the internet sharing under windows? The thing that says "allow other computers to connect to this computer and use it's internet". Then when you plug the switch into your desktop any other device you plug into your switch could connect to your desktop and use its internet?
I normally just find these things out by playing around, I'm sure others will have a much better ideas

Just to clarify, do mean set up like this?

WIRELESS

DESKTOP LAPTOP
|
SWITCH
|
OTHER PCs

 

Thats EXACTLY what Im going for lol. Yeah instead of going out an buying a linksys access point for like 70 bucks, Im trying to find out if its possible to use my desktop as one. Now in that setup you described ToMMo, would you happen to know if I would need a standard ethernet cable coming out of my computer going to the switch, or would it need to be a crossover cable?

 

standard cable from a pc to a switch.
crossover if between 2 pcs without a switch between them.

 

That was my initial thought...just thought Id check to be sure so thanks!