Without knowing model numbers it's hard to say exactly.
Cable Modems are normally connected via coaxial and then have one or several available RJ-45 Ethernet ports for connecting to your network, devices or in your case other routers.
Could you please clarify if this is a existing router that you own that you want to connect to the modem for more ports or extra connectivity, or is it one that you have received from your ISP with the Modem?
i hope to get this answered i got a UBEE DVW3201B MODEM its okay because its wifi and wireless but since i got it from time warner the wireless always go to a disabled position then i always have to contact TIME WARNER back and forth i feel im contacting them for nothing i could fix the problem one of the TIME WARNER worker told me to reset it to the factory so i did that and some times that worked and some times it didnt. so if anybody know info on how to enable wireless on a UBEE DVW3201B please contact me email@example.com im trying to save money my resident where i live only have us use TIME WARNER if we want a cable television thanks let hear from you