router / cable modem problem


I have rather suddenly lost functionality of my router. I have comcast cable modem ISP. Comcast tech came and swapped in new modem. I have a Belkin router. I just swapped in a new LinkSys router. No better. The router allows all three OSX machines on our home network to communicate, but none can get out through to the modem. Directly connecting one OSX machine to modem and resetting DHCP gets the comcast ISP fine. But router will not connect or residtribute IPs to machines. I've reset everything I know how to do in Network Prefs, and swapped cables. Any ideas?