Each computer has to have a fax/modem card connected to a phone line. You don't need to have 8 fax phone numbers, you could connect all of them to parralel lines under the same phone number. If you want to direct all faxes to one computer through your router, you would need to buy a network card, attach this card to your fax machine, and connect this network card directly to your router using ethernet cable (or wireless). Then you can send faxes from any computer to this network fax, and they will be faxed from your fax machine.
