Network_LLTD
Vista’s new networking interface, the Network and Sharing Center, allows you to check your connection status, troubleshoot connection problems, and see a graphical view of how the computers and devices on your network connect via the Network Map. It’s handy to have a visual of your network, especially when troubleshooting connection problems.
The heart of the Network Map is a discovery protocol called Link Layer Topology Discovery (LLTD). This protocol allows Vista systems to query the other devices on the network so it can determine how the network is organized. While Vista does a good job of creating the Network Map, including switches and gateways, it only places computers running Vista — not Windows XP or any other operating system — on the map. The reason for this discrepancy is that LLTD is a new feature in Vista and isn’t present in Windows XP.
To help users deal with this, Microsoft has released the LLTD Responder for Windows XP systems. Once you install the LLTD Responder, it will allow Vista to query Windows XP systems and place them in the appropriate locations on the Network Map.
In this issue of the Windows Vista Report, I’ll take a look at the Network and Sharing Center and the Network Map. I’ll then show you how to download and install the LLTD Responder for Windows XP systems.
When you first launch the Network and Sharing Center (which you do by accessing the Network and Internet category in the Control Panel), you’ll see that it’s a very well organized tool (Figure A). At the very top is a condensed view of the Network Map showing icons for the current system, the network, and the Internet. Beneath that image, you’ll find information about the current network connection, as well as information about resources that the system sees or shares on the network.
Figure A
At the very top of the Network and Sharing Center, you’ll find a condensed view of the Network Map.
The Tasks pane at the left provides access to common networking tasks, such as viewing computers and devices, connecting to a network, and diagnosing and repairing problems.
If you click the View Full Map link just above the Internet icon, you’ll see a more detailed map of the network (Figure B). However, this map only shows the Vista systems, along with the switches and gateway, with the icons for the Windows XP systems clumped together down at the bottom of the screen with this caption: The following discovered device(s) can not be placed in the map. Click here to see all other devices.
Figure B
By default, the Network Map will show only Vista systems, along with switches and gateways.
Downloading and installing the LLTD Responder is a snap in Windows XP. You’ll have to go through the Windows Genuine Advantage formalities before you can download the LLTD Responder, but then you can simply click the Run button and begin the Software Update Installation Wizard (Figure C).
Figure C
The wizard makes installing the LLTD Responder a quick four-step procedure.
Once the installation is complete, confirm that the LLTD Responder is running by right-clicking the My Network Places icon and selecting the Properties command. When you see the Network Connections folder, right-click the Local Area Network Connection and select the Properties command. Then, in the Local Area Network Connection Properties dialog box, make sure that the Link-Layer Topology Discovery Responder is present and that the check box is selected (Figure D).
Figure D
To verify that the LLTD Responder is installed on your Windows XP system, simply check the Local Area Connection Properties dialog box.
Now you can return to your Vista system and access the Network and Sharing Center. When you click the View Full Map link, Vista will build a new Network Map that includes all of your Windows XP systems (Figure E).
Figure E
Once the LLTD Responder is in place, Vista can build a complete Network Map.