The SB5100 is NOT a router. It is a cable modem ONLY. It connects to your broadband CATV line, and provides a single ETHERNET link downstream. This link has a cable-provider assigned IP address. Likely a dynamic address which changes periodically.
There are no setup features per se on a SB5100. That said, there typically is NO FILTERING enabled either, so nothing that needs to be SETUP for it to transport ALL traffic to your PC.