I have a cablemodem service that assigns me 3 fixed public IP address by DHCP. When I connect one computer ó router the cable company assign the first public IP that its free and when I call the company they fix that IP to the MAC of my computer. The modem that its provided by the cable company has only one Ethernet port, and in order to receive more than one public IP I have to put a switch between the modem and my equipments. The problem is when the cable modem fails or is rebooted, the computers behind the switch are unaware of this and don’t retry to obtain by DHCP the address and in the cablemodem system if you don’t get your address by DHCP the system don’t route anything to you. It’s any method to indicate that if the port connected to the cable modem goes Down Up the ports of the computers do the same?

thanks for any help you can give me.