the best thing to do is get something like a Netgear Cable modem/DSL router that uses NAT, (network address translation), what this will do is assign your broadband IP Address to the netgear router and then that router will assign IP addresses to all the pc’s on your local network. they usually have a 4 port switch built in also. this will also help block persons on the internet from trying to hack into your internal network. just make sure that after you install it that you go to one of the pc’s on the internal network, open your browser and point it to the address of the router, (usually 192.168.0.1 or 192.168.1.1). this will get you into the management pages of the router. change the password to something that is NOT easy to guess. make sure you read the manual and set the security up on it. good luck!
Just go on my network palace -properties-right click on broadband network connection -advance-click on share this connection on networkand and now give this pc’s ip to the client in gatewayand enjoy.