Windows XP has a new feature called Network Bridge, which lets you connect disparate media types into one seamless LAN. For example, if you have a network PC connected to a LAN, cable modem, or DSL modem via Ethernet, you can create a bridge between the Ethernet connection and your PC's FireWire connection.

When you connect a laptop to the desktop via FireWire, the Network Bridge provides an IP connection to the laptop, even though the laptop isn't connected directly into the network. To create a bridge, select two connections in the Network Connections control panel, then right-click on them and select Bridge Connections.

If you are bridging an Ethernet connection to a FireWire connection, you must manually set the IP address information (including IP address, gateway address, and DNS server address) on the FireWire-connected laptop, even if the LAN is configured to assign IP addresses automatically using a DHCP server. If you frequently connect the same laptop to the same desktop, you can use the alternate IP address configuration feature to set the IP address to use for the FireWire connection.