Network and Sharing Center
This feature is included in the following editions of Windows Vista:
The Network and Sharing Center puts you in control of your network connectivity. It's a place where you can check your connection status, view your network visually, and troubleshoot connection problems.N
The Network and Sharing Center informs you about your network and verifies whether your PC can successfully access the Internet—then summarizes this info in the form of a Network Map.
If any computer connected to your network loses Internet connectivity, the Network and Sharing Center provides a graphical representation of which connection is down. Then you can use Network Diagnostics and Troubleshooting to determine both the cause of the problem and possible ways to correct it.

A visual representation of your network.