To provide a quasi-hardware based, bandwidth prioritization setup, you can use the following configuration:
[This will require 2 IP addresses unless you use a router between the modem and hub (switch), OR your modem has LAN DHCP capability such as some cablemodems]
•Connect the ATA WAN port to one port on the hub (switch).
•Do not connect anything to (the ethernet port on) the ATA.
•Connect your LAN (other components) through *one* of the other ports on the hub (switch).
•Do not connect anything to the other hub (switch) ports.