With
earlier versions of Windows, you could use Network Neighborhood to
browse network resources such as shared folders and printers. However,
this system was inefficient because it relied on network broadcasts to
gather such information.
To fix this problem, Windows Vista introduced Link Layer Topology Discovery (LLTD),
which queries each device that supports Plug and Play Extensions
(PnP-X) or web services for devices to determine its capabilities and
to determine the topology of the network. It also uses version control
to keep the information current. It also describes the quality of
service (QoS) extensions that enable stream prioritization and quality
media streaming experiences, even on networks with limited bandwidth.
The
information that is gathered to create the network map and which
information the computer will give out to other Windows Vista computers
will depend on which network services that you have enabled or
configured using the Network and Sharing Center (see Table 1 and Figure 1).
Table 1. Network Services Managed with the Network and Sharing Center
| Feature | Settings | Result |
|---|
| Network Discovery. Allows this computer to see other network computers and devices and is visible to other network computers. | On | Turns on Network Discovery. |
| | Off | Turns off Network Discovery. |
| File sharing. Files and printers that you have shared from this computer can be accessed by people on the network. | On | Shares created on this computer can be accessed from the network. |
| | Off | Shares created on this computer cannot be accessed from the network. |
| Public folder sharing. People on the network can access files in the public folder. | Off | Only local users can access the Public folder. |
| | On (read) | Local and network users can read the contents of the Public folder, but cannot change them. |
| | On (change) | Local and network users can change the contents of the Public folder. |
| Printer sharing. Allows users to access shared printers. | On | Printers directly connected to this computer can be shared. |
| | Off | Printers directly connected to this computer cannot be shared. |
| Password-protected sharing.
Gives access to shared folders, including the Public folder, to users
who don’t have a username and password that corresponds to a user
account on the computer with the shared folder. | On (recommended) | People who access access shared folders must have corresponding local user account and password. |
| | Off | Computer sharing the folder does not require a user account or password. |
To
view the topology or to view the network resources, you open a network
folder or the Network and Sharing Center. However, a Windows Vista
computer will not be visible on the network map, and it will not be
able to map other hardware devices on the network until you enable
Network Discovery service. To see the full map, click the View Full Map
link in the Network and Sharing Center (see Figure 2).
