Uh...your broadband service is going to issue one ip address (unless you paid to have more). If you have more than one computer, they will be behind a device that does NAT (most likely a router). Thus, all outgoing traffic will share the same IP address. Internal to your LAN, each device has a separate IP address (issued most likely through DHCP). Are you saying that you're hosting some type of server that you want visible to the Internet? If so, you would need to follow the instructions of your router to expose it properly and safely...also, your broadband ISP may not let you do this.