I am putting in a Cablevision modem for the business on Fri.
I am sending internet access over a cat5 to my 1st floor to a Linksys wireless router for my laptops.

I also want a hard wire from modem to my desktop
about 3 feet from the modem.

What do i need downstairs to take the single port on the modem to the 2 outputs.

You would want to come off an ethernet port on your wireless router back to the desktop. Run two cables. Alternately you could use another router that feeds the wireless as well as your desktop but that would be silly.

-Hal

Thanks Hal
Sounds like a plan.
I have one already ,I will just run another Cat5.