linksys router and optimum on line

I recently switched from a DSL connection to Cable. I used a linksys router for the DSL PPoE connection rather than the supplied software. It worked great and I was able to network my laptop and desktop machines. Optonline doesn't "see" my router and won't give me a connection. I know I don't need the PPoE function with cable and have disabled it. What else do I need to do to get this router to work with the cable modem?