Take Control of Screen Sharing in Leopard

Appendix B. Configure Your Router or Gateway

To share a remote screen using Back to My Mac, or to do screen sharing via iChat, the Screen Sharing program, or VNC, you may need to make changes to the way in which your router controls access to your local network from the rest of the Internet.

In the ideal case, your gateway is directly connected to a broadband modem (or perhaps even integrated in the same box with it) and your ISP has a simple topology—network architecture. When you configure the gateway in this situation, you directly affect its remote accessibility over the public Internet.

In the worst case, your ISP has multiple layers of network address translation (NAT)—a way of sharing an Internet connection among multiple computers—that makes ...