I have a cable modem motorola sb6120 with one exit (3 little computers) a voip adapter grandstream ht-502 with 2 exit (LAN and WAN) and a wifi router trendnet tew-652brp with 5 exit (WAN,1,2,3,4) and i will like to connect my VOIP on to my cable modem first and connect wifi router to the VOIP adapter second. this is possible and how to do it?