Advanced Networking Services

Several Windows networking options and settings are difficult to categorize. These topics must be covered somewhere, so I've collected them here.

Setting Network Bindings

Windows lets you specify how network components are connected. As you learned in Chapter 15, "Overview of Windows XP Networking," a network uses many layers of components. Bindings are the connections between these components. Through bindings, you can control whether the file and printer sharing service can be reached by each installed protocol and through which network and/or dial-up adapters.

You'll find step-by-step instructions for setting bindings elsewhere in this book where necessary. Let me give you the general picture here, in case you're arriving at this topic through the index.

To set network bindings, open the Network Connections window, and select Advanced, Advanced Settings from the menu. Select the Adapters and Bindings tab, as shown in Figure 20.8.

Figure 20.8. On the Adapters and Bindings tab, you can sever the connection between specific network components.

Select a network adapter (such as Local Area Connection) in the upper part of the dialog. In the bottom, you can check and uncheck services and individual transport protocols to connect or disconnect these services from the selected network adapter.

To set bindings for dial-up connections, you must view the Properties pages of the individual dial-up connections. On the Networking tab, you can check which services and protocols are to be used across the connection.

Installing Optional Network Components

Windows XP Professional comes with a few networking components that are not used in most networks but can be essential in others. I won't cover these components in great detail because your network manager will probably install them for you if they're used on your LAN.

The optional components are listed in Table 20.6. The individual components can be selected for installation by following these steps:

1.	Open Network Connections by clicking Start, My Computer, My Network Places, View Network Connections.
2.	From the menu, select Advanced, Optional Networking Components.
3.	Highlight one of the three components categories listed in the Table and click Details.
4.	Check the box next to the desired component(s).

Table 20.6. Windows XP Optional Network Components

Category/Component	Description
Management and Monitoring Tools
Simple Network Management Protocol	A remote monitoring and measurement tool used by some network management systems. This protocol is discussed next.
WMI SNMP Provider	Allows Windows Management Instrumentation applications to access SNMP data.
Networking Services
Internet Gateway Device Discovery and Control Client	This service, installed by default, uses UPnP to automatically locate UPnP-capable routers (and Windows Internet Connection Sharing), and install icons for these on the Network Connections page. See the UPnP User Interface option.
Peer-to-Peer	Supports Windows Peer-to-Peer Networking distributed processing services; see www.microsoft.com/windowsxp/p2p.
RIP Listener	A service to receive network routing information in large networks. Your network manager will indicate whether you need to install it. Don't install unless it's required.
Simple TCP/IP Services	A suite of services that perform simple functions for testing purposes, such as echoing data to a remote computer or generating a stream of data. Don't install these services unless you're instructed to do so by a network manager. They don't do anything useful but can be used by hackers to tie up your network with pointless traffic.
UPnP User Interface	Allows Windows to discover and configure networked devices and appliances such as routers. This optional component supports more devices than the default Internet Gateway Device Discovery service. It also adds an exception in Windows Firewall to let incoming UPnP advertisements through the firewall. Icons for discovered devices appear in My Network Places. For more information, see "Using Universal Plug and Play" on p. 759.
Other Network File and Print Services
Print Services for UNIX	Printer services for UNIX hosts. These services were covered earlier in this chapter under "Printing to Windows Printers from UNIX."

Of these services, only SNMP is both useful and not covered elsewhere.

SNMP

The Simple Network Management Protocol, or SNMP, is used by large corporate networks to monitor, measure, and configure network equipment from a central location. It can be used, for example, by monitoring software to detect whether servers or WAN connections have gone offline to alert staff or sound an alarm.

Windows XP Professional doesn't come with a tool to use the information SNMP can reveal, but it does come with an optional networking component that lets an SNMP monitor measure network activity in your computer.

SNMP should not be installed unless your network administrator requires its use, as there are some security risks attached to it. If you do choose to install SNMP, you should immediately configure the SNMP monitor to protect your computer's information with a secret "community name." This name is like a password that remote monitors need to supply before they can extract information from your computer. The default community name is public. Your network manager might supply you with an alternate community name. To set it, do the following:

1.	Click Start, right-click My Computer, and select Manage.
2.	Open Services and Applications, select Services, and locate SNMP Service in the right pane. Double-click it to open its Properties page.
3.	Select the Security tab. Select Public, and then click Remove. Next, click Add to enter any community names provided by your network manager. Generally, assign only read-only community rights unless your network manager specifies otherwise.
4.	You can additionally restrict SNMP access to specific network hosts (namely, management computers) by selecting Accept SNMP Packets From These Hosts and adding the appropriate IP addresses.

CAUTION

SNMP can be a security risk because it reveals the names of user accounts on your computer and your computer's network routing information. A community name with write or create permission can alter network routing tables. For this reason, SNMP (UDP ports 161 and 162) should be blocked by your network's firewall, and you should not install it unless it's necessary.

TIP

If you're a network manager and use SNMP to monitor equipment health, you might find it valuable to know that Windows XP and 2000's Professional and Server versions come with a utility that can turn specified Windows Event Log entries into SNMP traps (messages) as they happen. This feature is configured by the poorly program evntwin. This utility can let your network monitor detect and report on full hard drives, security violations, and other significant events.

evntwin can save a list of event-to-trap mappings to a file. Another, evntcmd, can instantly install this file on another Windows XP or 2000 computer, even remotely. These two tools are installed when you install SNMP. Google "windows evntwin" and "windows evntcmd" for links to Microsoft and other documentation.