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Configuring wireless network settings on client computers

Applies To: Windows Server 2003, Windows Server 2003 R2, Windows Server 2003 with SP1, Windows Server 2003 with SP2

Configuring wireless network settings on client computers

The Wireless Configuration service in Windows XP and the Windows Server 2003 family supports the IEEE 802.11 standard for wireless networks and minimizes the configuration that is required to access wireless networks. This service is enabled by default and allows you to travel to different wireless networks without reconfiguring all of the network connection settings on your computer at each location. As you move from one location to another, the Wireless Configuration service searches and sends notifications when there are wireless networks available. When connecting to a new wireless network, you will need only to configure the settings specific to that network. The Wireless Configuration service updates your wireless network adapter to match those settings and attempts to connect to the wireless network.

The Windows Configuration service allows you to use Windows to configure your wireless network settings. When you use Windows to configure your wireless network settings, you can create a list of preferred wireless networks and you can specify the order in which to attempt connections to these networks.

For more information, see Define Wireless Network Policies on a Client Computer.

Viewing available 802.11 wireless networks

In addition to the wireless network notifications that are provided by the Wireless Configuration service, in Windows XP with Service Pack 2 and Windows Server 2003 with Service Pack 1, computers equipped with wireless network adapters have an enhanced interface called Wireless Network Connection.

The Wireless Network Connection interface was designed with several user benefits in mind. The interface makes it easier to view information about available 802.11 wireless networks, including network type (infrastructure or ad hoc), wireless signal strength, state (connected or disconnected), and whether networks are security enabled. The Wireless Network Connection interface also makes it easier to configure and control connections to 802.11 wireless networks. Direct access to 802.11 wireless properties, where both general 802.11 wireless settings and advanced configurations are made, can be accessed through the following interface links: Related Tasks, Change the order of preferred networks, and Change advanced settings.

To control connections to wireless networks, under Choose a wireless network, click Connect or Disconnect. To refresh the list of available wireless networks, use Network Tasks.

As an example, while attempting to connect to a wireless network, under Choose a wireless network, you might see status that reads Limited or no connectivity. Click the Limited or no connectivity link for more information, including possible remedies for connectivity problems.

Wireless icons

You can access the Wireless Network Connection interface by using new wireless icons that are provided in both the notification area and in Network Connections. To open the Wireless Network Connection interface, right-click the wireless icon, and then select View Available Wireless Networks. For more information, see Define Wireless Network Policies on a Client Computer.

Notification area wireless icons

In Windows XP with Service Pack 2 and Windows Server 2003 with Service Pack 1, wireless icons are displayed to indicate the state of the wireless connection:

Notification area icon Wireless connection state

Connected wireless notification area

Connected

Art Image

Connecting

Web link graphic

Not connected

MouseKeys illustration

Warning

The warning icon is displayed when an IP address error is detected while attempting to connect to a wireless network. In the event of an error, the warning icon will always be displayed in the notification area, provided the device has not been disabled or the Show icon in notification area when connected check box on the properties page of the device has not been cleared.

Note

  • When the wireless connection is in any of these states, you can right-click the wireless connection icon in the notification area and then select View Available Wireless Networks. Wireless adapters that have been disabled by right-clicking the wireless connection icon, and then clicking Disable, will not appear in the notification area. Disabled wireless adapters can be enabled only by right-clicking the wireless network connection icon in Network Connections, and then clicking Enable.

Network Connections wireless icons

There are five views that can be applied to icons in Network Connections: Thumbnails, Tiles, Icons, List, and Details. In each of these views, the various states of wireless connections are represented in a similar way to the wireless icons in the notification area. For example, a wireless icon with a red X indicates there is no connection to a wireless network; a wireless icon with a yellow triangle indicates an error state.

Wireless icons in Network Connections do not indicate connecting or transitioning states. However, if you select the wireless icon and then expand Details in the left-hand pane, you have access to the following information:

Information type Example or explanation:

Connection status

  • Acquiring Network address

  • Not connected, Firewalled

  • Connected, Firewalled

Assigned IP Address

Displays the IP address that is assigned to the wireless adapter

Subnet Mask

Displays the associated subnet mask.

Method of IP address and subnet mask assignment

  • Assigned by DHCP

  • Manually Configured

Network type

  • Access Point

  • Peer-to-Peer (same as computer to computer)

Network

The name of the network. This is also known as the SSID.

Signal Strength:

Excellent

Selecting a wireless network type

When you configure new or existing wireless network connections or connect to an available wireless network, you can choose from the following wireless network types:

  • Access point (infrastructure)

    In access point wireless networks, wireless clients (computing devices with wireless network adapters, such as your portable computer or personal digital assistant) connect to wireless access points. The access points function as bridges between wireless clients and the existing network backbone. As you move from one location to another, and the signal for one wireless access point weakens, or the access point becomes congested with traffic, you can connect to a new access point. For example, if you work in a large corporation, you might connect to several different wireless access points as you move between different floors of a building or different buildings in a campus, while still maintaining uninterrupted access to network resources.

  • Computer-to-computer (ad hoc)

    In computer-to-computer wireless networks, wireless clients connect to each other directly, rather than through wireless access points. For example, if you are in a meeting with co-workers, and you do not need to gain access to network resources, your wireless device can make direct connections to the wireless devices of your co-workers, and you can form a temporary network.

  • Any available network (access point preferred)

    In access point preferred wireless networks, a connection to an access point wireless network is always attempted first, if there are any available. If an access point network is not available, a connection to a computer-to-computer wireless network is attempted. For example, if you use your laptop at work in an access point wireless network, and then you take your laptop home to use in your computer-to-computer home network, the Windows Configuration service will change your wireless network settings as needed so that you can connect to your home network.

Configuring wireless network security settings

802.1X is an IEEE standard for authenticated network access to wired Ethernet networks and wireless 802.11 networks. IEEE 802.1X enhances security and deployment by providing support for centralized user identification, authentication, dynamic key management, and accounting. For enhanced security in Windows XP Service Pack 1 and the Windows Server 2003 family, 802.1X authentication is available only for access point (infrastructure) networks that require the use of a network key (WEP). Wired Equivalent Privacy (WEP) provides data confidentiality by encrypting the data that is sent between wireless clients and wireless access points.

Important

  • It is highly recommended that you use 802.1X authentication whenever you connect to an 802.11 wireless network. If you connect to an 802.11 wireless network without using 802.1X authentication, the data that you send is more vulnerable to attacks, such as offline traffic analysis, bit flipping, and malicious packet injection. For more information about security considerations for wireless networks, see Security information for wireless networks.

Configuring wireless network key settings

When Wired Equivalent Privacy (WEP) is enabled, a network key can be used to encrypt data that is sent over wireless networks. The network key can be provided for you automatically (for example, if 802.1X is being used for dynamic key distribution), or you can specify the key by typing it yourself. If you specify the key yourself, you can also specify the key index (the location where a specific key is stored).

A wireless client can be configured with up to four keys (the key index values are 0, 1, 2, and 3). When a wireless access point or a wireless client transmits an encrypted message using a key that is stored in a specific key index, the transmitted message indicates the key index that was used to encrypt the message body. The receiving wireless access point or wireless client can retrieve the key that is stored at the key index and use it to decode the encrypted message body.

Important

  • To enhance security and connectivity, do not use shared key authentication. Shared key authentication is less secure than open system authentication because it requires the exchange of a secret key that is shared by all wireless access points and clients and therefore is more vulnerable to known-text attacks. In addition, if you use shared key authentication for a wireless network that has multiple wireless access points, you will lose network connectivity when you travel from one wireless access point to a new wireless access point. In this case, you will lose connectivity because your network key will no longer match the shared key used by all wireless access points. To determine whether a wireless network you are connecting to has multiple wireless access points, use Wireless Monitor. For information about how to use Wireless Monitor to view details about wireless access points, see View details about wireless network access points.

Configuring 802.1X authentication settings for wireless network connections

The support that 802.1X provides for Extensible Authentication Protocol (EAP) types allows you to select from several authentication methods for wireless network connections. For more information about choosing an authentication method, see Understanding 802.1X authentication for wireless networks.