Configuring the Client Adapter
This chapter explains how to configure profile parameters. The following topics are covered in this chapter:
•Overview
•Setting General Parameters
•Setting Advanced Parameters
•Setting Security Parameters
•Enabling Wi-Fi Multimedia
•Setting Roaming Parameters in the Windows Control Panel
Overview
When you choose to create a new profile or modify an existing profile on the Cisco Aironet Desktop Utility (Profile Management) window, the Profile Management windows appear. These windows enable you to set the configuration parameters for that profile.
Note If you do not change any of the configuration parameters for a newly created profile, the default values are used.
Note If you are planning to set parameters on more than one of the Profile Management windows, wait until you are finished with all of the windows before clicking OK. When you click OK, you are returned to the Cisco Aironet Desktop Utility (Profile Management) window.
Each of the Profile Management windows (listed below) contains parameters that affect a specific aspect of the client adapter:
•General—Prepares the client adapter for use in a wireless network
•Advanced—Controls how the client adapter operates within an infrastructure or ad hoc network
•Security—Controls how a client adapter associates to an access point, authenticates to the wireless network, and encrypts and decrypts data
Table 5-1 enables you to quickly locate instructions for setting each Profile Management window's parameters.
Note If your system administrator used an administrative tool to deactivate certain parameters, these parameters are disabled on the Profile Management windows and cannot be selected.
Note You can also set two roaming parameters for your client adapter outside of ADU using the Windows Control Panel. Refer to the "Setting Roaming Parameters in the Windows Control Panel" section for details.
Setting General Parameters
The Profile Management (General) window (see Figure 5-1) enables you to set parameters that prepare the client adapter for use in a wireless network. This window appears after you click New or Modify on the Cisco Aironet Desktop Utility (Profile Management) window.
Figure 5-1 Profile Management (General) Window
Table 5-2 lists and describes the client adapter's general parameters. Follow the instructions in the table to change any parameters.
Table 5-2 Profile Management General Parameters
|
|
Profile Name |
The name assigned to the configuration profile.
Range: You can key in up to 32 ASCII characters.
|
Client Name |
A logical name for your workstation. It enables an administrator to ascertain which devices are connected to the access point without having to memorize every MAC address. This name is included in the access point's list of connected devices. The client name is filled in automatically but can be changed.
Range: You can key in up to 16 ASCII characters.
Default: The name of your computer
Note Each computer on the network should have a unique client name. |
SSID1 |
The service set identifier (SSID) identifies the specific wireless network that you want the client adapter to access.
Range: You can key in up to 32 ASCII characters (case sensitive).
Note If you leave this parameter blank, your client adapter can associate to any access point on the network that is configured to allow broadcast SSIDs. If the access point with which the client adapter is to communicate is not configured to allow broadcast SSIDs, the value of this parameter must match the SSID of the access point. Otherwise, the client adapter is unable to access the network. Note You must enter an SSID if this profile is configured for use in an ad hoc network. |
SSID2 |
An optional SSID that identifies a second distinct network and enables the client adapter to roam to that network without having to be reconfigured.
Range: You can key in up to 32 ASCII characters (case sensitive).
Note If a profile specifies more than one SSID, it cannot be included in auto profile selection or used with WPA/WPA2 passphrase. Note This field is unavailable for any profiles that are included in auto profile selection or configured for use in an ad hoc network. |
SSID3 |
An optional SSID that identifies a third distinct network and enables the client adapter to roam to that network without having to be reconfigured.
Range: You can key in up to 32 ASCII characters (case sensitive).
Note If a profile specifies more than one SSID, it cannot be included in auto profile selection or used with WPA/WPA2 passphrase. Note This field is unavailable for any profiles that are included in auto profile selection or configured for use in an ad hoc network. |
Go to the next section to set additional parameters, or click OK to save your changes and return to the Cisco Aironet Desktop Utility (Profile Management) window.
Setting Advanced Parameters
The Profile Management (Advanced) window (see Figure 5-2) enables you to set parameters that control how the client adapter operates within an infrastructure or ad hoc network. To open this window, click the Advanced tab from any Profile Management window.
Figure 5-2 Profile Management (Advanced) Window
Table 5-3 lists and describes the client adapter's advanced parameters. Follow the instructions in the table to change any parameters.
Table 5-3 Profile Management Advanced Parameters
|
|
Transmit Power Level |
Specifies the preferred power level at which your client adapter transmits. Although the adapter supports up to 100 mW, the transmit power level that is actually used is limited to the maximum value allowed by your country's regulatory agency (FCC in the U.S., DOC in Canada, ETSI in Europe, TELEC in Japan, etc.).
Options: Dependent on the radio band used and the power table programmed into the client adapter; see the table below.
Default: The maximum power level programmed into the client adapter and allowed by your country's regulatory agency
|
Radio Band |
Transmit Power Level |
802.11b/g |
10, 20, 32, 50, 63, or 100 mW |
802.11a |
10, 13, 20, 25, or 40 mW |
Note The client adapter's maximum transmit power level may be lower when operating in 802.11g mode than when operating in 802.11b mode due to 802.11g-specific regulatory limitations in some countries. Note Reducing the transmit power level conserves battery power but decreases radio range. Note If configured to control the client power level, access points can limit the maximum power of the client. |
Power Save Mode |
Sets your client adapter to its optimum power consumption setting.
Options: CAM (Constantly Awake Mode), Fast PSP (Power Save Mode), or Max PSP (Max Power Saving)
Default: CAM (Constantly Awake Mode)
|
Power Save Mode |
Description |
CAM (Constantly Awake Mode) |
Keeps the client adapter powered up continuously so there is little lag in message response time. Consumes the most power but offers the highest throughput. Is recommended for desktop computers and devices that use AC power. |
Fast PSP (Power Save Mode) |
Switches between PSP mode and CAM mode, depending on network traffic. This mode switches to CAM when retrieving a large number of packets and switches back to PSP after the packets have been retrieved. Is recommended when power consumption is a concern but you need greater throughput than that allowed by Max PSP. |
Max PSP (Max Power Saving) |
Causes the access point to buffer incoming messages for the client adapter, which wakes up periodically and polls the access point to see if any buffered messages are waiting for it. The adapter can request each message and then go back to sleep. Conserves the most power but offers the lowest throughput. Is recommended for devices for which power consumption is the ultimate concern (such as small battery-powered devices). |
Note If this profile is configured for use in an ad hoc network, CAM mode is used automatically. |
Network Type |
Specifies the type of network in which your client adapter is installed.
Options: Infrastructure or Ad Hoc
|
Network Type |
Description |
Ad Hoc |
Often referred to as peer to peer. Indicates that your wireless network consists of a few wireless devices that are not connected to a wired Ethernet network through an access point. For example, an ad hoc network could be set up between computers in a conference room so that users can share information in a meeting. |
Infrastructure |
Indicates that your wireless network is connected to a wired Ethernet network through an access point. |
802.11b Preamble |
Determines whether your client adapter uses both short and long radio headers or only long radio headers. The adapter can use short radio headers only if the access point is also configured to support them and is using them. If any clients associated to an access point are using long headers, then all clients in that cell must use long headers, even if both this client and the access point have short radio headers enabled. Short radio headers improve throughput performance; long radio headers ensure compatibility with clients and access points that do not support short radio headers.
Options: Short & Long or Long Only
Note This parameter is disabled if the Wireless Mode parameter does not include the 2.4 GHz 11 Mbps option. |
Wireless Mode |
Specifies the frequency and rate at which your client adapter should transmit packets to or receive packets from access points.
Options: 5 GHz 54 Mbps, 2.4 GHz 54 Mbps, and 2.4 GHz 11 Mbps
Default: All options selected
Note When more than one option is selected, the client adapter attempts to use the wireless modes in this order: 5 GHz 54 Mbps, 2.4 GHz 54 Mbps, 2.4 GHz 11 Mbps. Note If you choose 2.4 GHz 11 Mbps, the client adapter can associate to access points containing an 802.11b or 802.11g radio at 802.11b data rates. If you choose 2.4 GHz 54 Mbps, the client adapter can associate to access points containing an 802.11b radio at 802.11b data rates or to access points containing an 802.11g radio at 802.11b or 802.11g data rates. Note When you enable auto profile selection, the client adapter ignores the selected profile's wireless mode setting and scans the wireless modes specified by all the profiles in the auto profile selection list for an available network. Using this method, the client does not need to disassociate nor change the current profile while looking for networks in other profiles. Note Your client adapter's wireless mode must match that of the access points with which it is to communicate. Otherwise, your client adapter may not be able to associate to them. |
Wireless Mode When Starting Ad Hoc Network |
Specifies the frequency and rate at which your client adapter should transmit packets to or receive packets from other clients (in ad hoc mode).
Options: 5 GHz 54 Mbps, 2.4 GHz 11 Mbps, or 2.4 GHz 54 Mbps
Note The client scans the band(s) specified by the Wireless Mode parameter before creating a new ad hoc cell based on the band specified by the Wireless Mode When Starting Ad Hoc Network parameter. Note Your client adapter's wireless mode must match that of the other clients with which it is to communicate. Otherwise, your client adapter may not be able to associate to them. Note The 2.4 GHz 54 Mbps wireless mode may not be functional on some vendors' products. In this case, the client adapter uses the 2.4 GHz 11 Mbps wireless mode. |
Channel |
Specifies the channel that your client adapter uses for communications in a 2.4-GHz ad hoc network. The available channels conform to the IEEE 802.11 Standard for your regulatory domain. The channel of the client adapter must be set to match the channel used by the other clients in the wireless network. If the client adapter does not find any other ad hoc clients, this parameter specifies the channel with which the adapter will start its cell.
Range: Dependent on regulatory domain
Example: 1 to 11 (2412 to 2462 MHz) in North America
Default: Auto (the client automatically determines the channel on which to start communications)
Note This parameter is available only when 2.4 GHz 11 Mbps or 2.4 GHz 54 Mbps is selected for the Wireless Mode When Starting Ad Hoc Network parameter. When 5 GHz 54 Mbps is selected, the Channel parameter is set to Auto automatically. Note Refer to Appendix D, for a list of channel identifiers, channel center frequencies, and regulatory domains for each channel. |
802.11 Authentication Mode |
Specifies how your client adapter attempts to authenticate to an access point. Open and shared authentication do not rely on a RADIUS server on your network.
Options: Auto, Open, or Shared
Default: Open |
802.11 Authentication Mode
|
|
Auto |
Causes the client adapter to attempt to authenticate using shared authentication. If it fails, the client adapter then attempts to authenticate using open authentication. |
Open |
Enables your client adapter, regardless of its WEP settings, to authenticate and attempt to communicate with an access point. However, communication can occur only if the adapter's WEP key matches that of the access point. |
Shared |
Enables your client adapter to authenticate and communicate only with access points that have the same WEP key. During shared key authentication, the access point sends an unencrypted challenge packet to the client adapter, which encrypts the packet and sends it back to the access point. The access point attempts to decrypt the encrypted packet and sends an authentication response packet indicating the success or failure of the decryption back to the client adapter. If the packet is successfully encrypted/ decrypted, the user is considered to be authenticated. |
Note Cisco recommends that Auto and Shared not be used because they present a security risk. Note Your client adapter's 802.11 authentication mode setting must match that of the access points with which it is to communicate, or be set to auto. Otherwise, your client adapter may not be able to authenticate to them. Note If this profile is configured for use in an ad hoc network or is not configured to use static WEP, this parameter is unavailable, and Open authentication is used. |
If this profile is configured for use in an infrastructure network and you want to specify up to four access points to which the client adapter should attempt to associate, click Preferred APs. The Preferred Access Points window appears (see Figure 5-3).
Figure 5-3 Preferred Access Points Window
Leave the Access Point 1 through Access Point 4 fields blank or enter the MAC addresses of up to four preferred access points to which the client adapter can associate; then click OK. (The MAC address should consist of 12 hexadecimal characters.) If the specified access points are not found or the client adapter roams out of range, the adapter may associate to another access point.
Go to the next section to set additional parameters or click OK to save your changes and return to the Cisco Aironet Desktop Utility (Profile Management) window.
Setting Security Parameters
The Profile Management (Security) window (see Figure 5-4) enables you to set parameters that control how the client adapter associates to an access point, authenticates to the wireless network, and encrypts and decrypts data. To access this window, click the Security tab from any Profile Management window.
Figure 5-4 Profile Management (Security) Window
This window is different from the other Profile Management windows in that it includes many security features, each of which involves a number of steps. In addition, the security features themselves are complex and need to be understood before they are implemented. Therefore, this section provides an overview of the security features as well as procedures for enabling them.
Note If your system administrator used an administrative tool to lock this profile, the Profile Locked check box is checked. Locked profiles cannot be modified (with the exception of password fields), written over, or removed.
Overview of Security Features
You can protect your data as it is transmitted through your wireless network by encrypting it through the use of wired equivalent privacy (WEP) encryption keys. With WEP encryption, the transmitting device encrypts each packet with a WEP key, and the receiving device uses that same key to decrypt each packet.
The WEP keys used to encrypt and decrypt transmitted data can be statically associated with your adapter or dynamically created as part of the EAP authentication process. The information in the "Static WEP Keys" and "EAP (with Dynamic WEP Keys)" sections below can help you to decide which type of WEP keys you want to use. Dynamic WEP keys with EAP offer a higher degree of security than static WEP keys.
WEP keys, whether static or dynamic, are either 40 or 128 bits in length. 128-bit WEP keys offer a greater level of security than 40-bit WEP keys.
Note Refer to the "Additional WEP Key Security Features" section for information on three security features that can make your WEP keys even more secure.
Static WEP Keys
Each device (or profile) within your wireless network can be assigned up to four static WEP keys. If a device receives a packet that is not encrypted with the appropriate key (as the WEP keys of all devices that are to communicate with each other must match), the device discards the packet and never delivers it to the intended receiver.
You do not need to re-enter static WEP keys each time the client adapter is inserted or the Windows device is rebooted because the keys are stored (in an encrypted format for security reasons) in the registry of the Windows device. When the driver loads and reads the client adapter's registry parameters, it also finds the static WEP keys, unencrypts them, and stores them in volatile memory on the adapter.
The Define Pre-Shared Keys window enables you to view the WEP key settings for a particular profile and to assign new WEP keys or overwrite existing WEP keys. Refer to the "Enabling Static WEP" section for instructions.
EAP (with Dynamic WEP Keys)
The standard for wireless LAN security, as defined by IEEE, is called 802.1X for 802.11, or simply 802.1X. An access point that supports 802.1X and its protocol, Extensible Authentication Protocol (EAP), acts as the interface between a wireless client and an authentication server, such as a RADIUS server, to which the access point communicates over the wired network.
Five 802.1X authentication types are available in ADU for use with Windows 2000 or XP:
•EAP-Cisco Wireless (or LEAP)—This authentication type leverages Cisco Key Integrity Protocol (CKIP) and MMH message integrity check (MIC) for data protection. ADU offers a variety of LEAP configuration options, including how a username and password are entered to begin the authentication process.
The username and password are used by the client adapter to perform mutual authentication with the RADIUS server through the access point. The username and password need to be re-entered each time the client adapter is inserted or the Windows device is rebooted unless you configure your adapter to use saved LEAP credentials.
RADIUS servers that support LEAP include Cisco Secure ACS release 2.6 or later, Cisco Access Registrar release 1.7 or later, Funk Software's Steel-Belted RADIUS release 4.1 or later, and Meetinghouse Data Communications' AEGIS release 1.1 or later.
•EAP-FAST—This authentication type (Flexible Authentication via Secure Tunneling) uses a three-phased tunneled authentication process to provide advanced 802.1X EAP mutual authentication.
–Phase 0 enables the client to dynamically provision a protected access credential (PAC) when necessary. During this phase, a PAC is generated securely between the user and the network.
–Phase 1 uses the PAC to establish a mutually authenticated and secure tunnel between the client and the RADIUS server. RADIUS servers that support EAP-FAST include Cisco Secure ACS version 3.2.3 and later.
–Phase 2 performs client authentication in the established tunnel.
ADU offers a variety of EAP-FAST configuration options, including how and when a username and password are entered to begin the authentication process and whether automatic or manual PAC provisioning is used.
The client adapter uses the username, password, and PAC to perform mutual authentication with the RADIUS server through the access point. The username and password need to be re-entered each time the client adapter is inserted or the Windows device is rebooted unless you configure your adapter to use saved EAP-FAST credentials.
PACs are created by Cisco Secure ACS and are identified by an ID. The user obtains his or her own copy of the PAC from the server, and the ID links the PAC to the profile created in ADU. When manual PAC provisioning is enabled, the PAC is manually copied from the server and imported onto the client device. The following rules govern PAC storage:
–PACs are stored as encrypted data files in either the global or private store on the user's computer.
· Global PACs can be accessed and used by any user at any logon stage. They are available before or during logon or after the user is logged off if the profile is not configured with the No Network Connection Unless User Is Logged In option.
· Private PACs can be accessed and used only by the user who provisioned them or the system administrator.
Note Global PACs are stored on C:\Document and Settings\All Users\Application Data\Cisco\cscostore, and private PACs are stored on C:\Document and Settings\user\
Application Data\Cisco\cscostore.
–If automatic PAC provisioning is enabled and it occurs after the user is logged on, the PAC is stored in the private store of the currently logged-on user. Otherwise, the PAC is stored in the global store.
–PAC files can be added or overwritten using the import feature.
–PAC files can be removed using the delete feature. They are also deleted when you uninstall the client adapter software.
–PAC files are tied to the machine, so they cannot be used if copied to another machine.
EAP-FAST authentication is designed to support the following user databases over a wireless LAN:
–Cisco Secure ACS internal user database
–Cisco Secure ACS ODBC user database
–Windows NT/2000/2003 domain user database
–LDAP user database
LDAP user databases (such as NDS) support only manual PAC provisioning while the other three user databases support both automatic and manual PAC provisioning.
Note PACs that are created by ACS version 3.x.xx are not compatible with ACS version 4.0.xx. Client stations must import new PACs. If you select auto-provisioning, new PACs will automatically be generated and used. However, if you select manual provisioning, you must manually export new PACs to the client stations. If a user wants to authenticate to ACS version 4.0.xx and version 3.x.xx at different times, both PACs must remain on the client station. The ADU is capable of automatically selecting the appropriate PAC. However, if you experiences authentication failures after upgrading the software, delete all the PACs provisioned from the 3.x.xx server.
•EAP-TLS—This authentication type uses a dynamic session-based WEP key derived from the client adapter and RADIUS server to encrypt data. It uses a client certificate for authentication.
RADIUS servers that support EAP-TLS include Cisco Secure ACS release 3.0 or later and Cisco Access Registrar release 1.8 or later.
•PEAP (EAP-GTC)—This PEAP authentication type is designed to support One-Time Password (OTP), Windows NT or 2000 domain, and LDAP user databases over a wireless LAN. It is based on EAP-TLS authentication but uses a password instead of a client certificate for authentication. PEAP (EAP-GTC) uses a dynamic session-based WEP key derived from the client adapter and RADIUS server to encrypt data. If your network uses an OTP user database, PEAP (EAP-GTC) requires you to enter a hardware or software token password to start the EAP authentication process and gain access to the network. If your network uses a Windows NT or 2000 domain user database or an LDAP user database (such as NDS), PEAP (EAP-GTC) requires you to enter your username, password, and domain name in order to start the authentication process.
RADIUS servers that support PEAP (EAP-GTC) authentication include Cisco Secure ACS release 3.1 or later.
•PEAP (EAP-MSCHAP V2)—This PEAP authentication type is based on EAP-TLS authentication but uses a password or client certificate for authentication. PEAP (EAP-MSCHAP V2) uses a dynamic session-based WEP key derived from the client adapter and RADIUS server to encrypt data.
RADIUS servers that support PEAP (EAP-MSCHAP V2) authentication include Cisco Secure ACS release 3.2 or later.
When you configure your access point as indicated in Table 5-4 and configure your client adapter for LEAP, EAP-FAST, EAP-TLS, PEAP (EAP-GTC), or PEAP (EAP-MSCHAP V2), authentication to the network occurs in the following sequence:
1. The client associates to an access point and begins the authentication process.
Note The client does not gain full access to the network until authentication between the client and the RADIUS server is successful.
2. Communicating through the access point, the client and RADIUS server complete the authentication process, with the password (LEAP and PEAP), PAC (EAP-FAST), or certificate (EAP-TLS and PEAP) being the shared secret for authentication. The password and PAC are never transmitted during the process.
3. If authentication is successful, the client and RADIUS server derive a dynamic, session-based WEP key that is unique to the client.
4. The RADIUS server transmits the key to the access point using a secure channel on the wired LAN.
5. For the length of a session, or time period, the access point and the client use this key to encrypt or decrypt all unicast packets (and broadcast packets if the access point is set up to do so) that travel between them.
Refer to the following pages for instructions on enabling these EAP types:
•LEAP, page 5-29
•EAP-FAST, page 5-34
•EAP-TLS, PEAP (EAP-GTC), or PEAP (EAP-MSCHAP V2), page 5-44
Note Refer to the IEEE 802.11 Standard for more information on 802.1X authentication and to the following URL for additional information on RADIUS servers:
http://www.cisco.com/en/US/products/sw/iosswrel/ps1835/products_configuration_guide_chapter09186a00800ca7ab.html
WPA and WPA2
Wi-Fi Protected Access (WPA) and WPA2 are standards-based security solutions from the Wi-Fi Alliance that provide data protection and access control for wireless LAN systems. WPA is compatible with the IEEE 802.11i standard but was implemented prior to the standard's ratification; WPA2 is the Wi-Fi Alliance's implementation of the ratified IEEE 802.11i standard.
WPA uses Temporal Key Integrity Protocol (TKIP) and message integrity check (MIC) for data protection while WPA2 uses the stronger Advanced Encryption Standard encryption algorithm using Counter Mode with Cipher Block Chaining Message Authentication Code Protocol (AES-CCMP). Both WPA and WPA2 use 802.1X for authenticated key management.
Both WPA and WPA2 support two mutually exclusive key management types: WPA/WPA2 and WPA/WPA2 passphrase (also known as WPA pre-shared key or WPA-PSK). Using WPA or WPA2, clients and the authentication server authenticate to each other using an EAP authentication method, and the client and server generate a pairwise master key (PMK). The server generates the PMK dynamically and passes it to the access point. Using WPA or WPA2 passphrase, however, you configure a passphrase (or pre-shared key) on both the client and the access point, and that passphrase is used as the PMK.
Refer to the following pages for instructions on enabling these WPA variations:
•WPA/WPA2 passphrase, page 5-28
•LEAP with WPA/WPA2, page 5-29
•EAP-FAST with WPA/WPA2, page 5-34
•EAP-TLS with WPA/WPA2, page 5-45
•PEAP (EAP-GTC) with WPA/WPA2, page 5-48
•PEAP (EAP-MSCHAP V2) with WPA/WPA2, page 5-52
Note WPA must also be enabled on the access point. To use WPA, access points must use Cisco IOS Release 12.2(11)JA or later. To use WPA2, access points must use Cisco IOS Release 12.3(2)JA or later. Refer to the documentation for your access point for instructions on enabling this feature.
CCKM Fast Secure Roaming
Some applications that run on a client device may require fast roaming between access points. Voice applications, for example, require it to prevent delays and gaps in conversation. CCKM fast secure roaming is enabled automatically for CB21AG and PI21AG clients using WPA/WPA2/CCKM with LEAP, EAP-FAST, EAP-TLS, PEAP (EAP-GTC), or PEAP (EAP-MSCHAP V2). However, this feature must be enabled on the access point.
During normal operation, EAP-enabled clients mutually authenticate with a new access point by performing a complete EAP authentication, including communication with the main RADIUS server. However, when you configure your wireless LAN for CCKM fast secure roaming, EAP-enabled clients securely roam from one access point to another without the need to reauthenticate with the RADIUS server. Using Cisco Centralized Key Management (CCKM), an access point that is configured for wireless domain services (WDS) uses a fast rekeying technique that enables Cisco client devices to roam from one access point to another typically in under 150 milliseconds (ms). CCKM fast secure roaming ensures that there is no perceptible delay in time-sensitive applications such as wireless Voice over IP (VoIP), enterprise resource planning (ERP), or Citrix-based solutions.
Note If you want to enable CCKM fast secure roaming on the client adapter, you must choose the WPA/WPA2/CCKM security option on the Profile Management (Security) window, regardless of whether you want the adapter to use WPA or WPA2. The configuration of the access point to which your client adapter associates determines whether CCKM will be used with 802.1x, WPA, or WPA2.
Note Access points must use Cisco IOS Release 12.2(11)JA or later to enable CCKM fast secure roaming. Refer to the documentation for your access point for instructions on enabling this feature.
Note The Microsoft Wireless Configuration Manager and the Microsoft 802.1X supplicant, if installed, must be disabled in order for CCKM fast secure roaming to operate correctly. If your computer is running Windows XP and you chose to configure your client adapter using ADU during installation, these features should already be disabled. Similarly, if your computer is running Windows 2000, the Microsoft 802.1X supplicant, if installed, should already be disabled. Refer to Chapter 10, if you need additional information.
Reporting Access Points that Fail LEAP Authentication
The CB21AG and PI21AG client adapters and the following access point firmware versions support a feature that is designed to detect access points that fail LEAP authentication:
•12.00T or later (access points running VxWorks)
•Cisco IOS Release 12.2(4)JA or later (1100 series access points)
•Cisco IOS Release 12.2(8)JA or later (1200 series access points)
•Cisco IOS Release 12.2(13)JA or later (350 series access points)
•Cisco IOS Release 12.3(4)JA (1130 series and BR 1310 series access points)
•Cisco IOS Release 12.3(7)JA (1240 series access points)
An access point running one of these firmware versions records a message in the system log when the client discovers and reports another access point in the wireless network that has failed LEAP authentication.
The process takes place as follows:
1. A client with a LEAP profile attempts to associate to access point A.
2. Access point A does not handle LEAP authentication successfully, perhaps because the access point does not understand LEAP or cannot communicate to a trusted LEAP authentication server.
3. The client records the MAC address for access point A and the reason why the association failed.
4. The client associates successfully to access point B.
5. The client sends the MAC address of access point A and the reason code for the failure to access point B.
6. Access point B logs the failure in the system log.
Note This feature does not need to be enabled on the client adapter or access point; it is supported automatically by both devices. However, the access points must use the specified firmware versions or later.
Additional WEP Key Security Features
The three security features discussed in this section (MIC, TKIP, and broadcast key rotation) are designed to prevent sophisticated attacks on your wireless network's WEP keys. These features do not need to be enabled on the client adapter; they are supported automatically in the client adapter software. However, they must be enabled on the access point.
Note Refer to the documentation for your access point for instructions on enabling these security features.
Message Integrity Check (MIC)
MIC prevents bit-flip attacks on encrypted packets. During a bit-flip attack, an intruder intercepts an encrypted message, alters it slightly, and retransmits it, and the receiver accepts the retransmitted message as legitimate. The MIC adds a few bytes to each packet to make the packets tamper-proof.
The Advanced Status window indicates if MIC is being used, and the Advanced Statistics window provides MIC statistics.
Temporal Key Integrity Protocol (TKIP)
This feature, also referred to as WEP key hashing, defends against an attack on WEP in which the intruder uses the initialization vector (IV) in encrypted packets to calculate the WEP key. TKIP removes the predictability that an intruder relies on to determine the WEP key by exploiting IVs. It protects both unicast and broadcast WEP keys.
Note TKIP is enabled automatically when WPA is enabled.
Broadcast Key Rotation
When you enable broadcast WEP key rotation, the access point provides a dynamic broadcast WEP key and changes it at the interval you select.
Synchronizing Security Features
In order to use any of the security features discussed in this section, both your client adapter and the access point to which it will associate must be set appropriately. Table 5-4 indicates the client and access point settings required for each security feature. This chapter provides specific instructions for enabling the security features on your client adapter. Refer to the documentation for your access point for instructions on enabling any of these features on the access point.
Table 5-4 Client and Access Point Security Settings
|
|
|
Static WEP with open authentication |
Choose Open authentication and Pre-Shared Key (Static WEP) and create a WEP key |
Set up and enable WEP and enable Open Authentication for the SSID |
Static WEP with shared key authentication |
Choose Shared authentication and Pre-Shared Key (Static WEP) and create a WEP key |
Set up and enable WEP and enable Shared Key Authentication for the SSID |
WPA or WPA2 passphrase (or WPA or WPA2 pre-shared key) |
Choose WPA/WPA2 Passphrase and enter the passphrase |
Choose a cipher suite, enable Open Authentication and WPA for the SSID, and enter a WPA pre-shared key Note To allow both WPA and non-WPA clients to use the SSID, enable optional WPA. |
LEAP authentication |
Choose 802.1x and LEAP; then set LEAP settings |
Set up and enable WEP and enable Network-EAP Authentication for the SSID |
LEAP authentication with WPA or WPA2 |
Choose WPA/WPA2/CCKM and LEAP; then set LEAP settings |
For WPA, choose a cipher suite that includes TKIP and enable Network-EAP and Open with EAP Authentication and WPA for the SSID For WPA2, choose a cipher suite that includes AES-CCMP and enable Network-EAP and Open with EAP Authentication and WPA for the SSID Note To allow both WPA and non-WPA clients to use the SSID, enable optional WPA. |
EAP-FAST authentication |
Choose 802.1x and EAP-FAST, set EAP-FAST settings, and enable automatic provisioning or import a PAC file |
Set up and enable WEP and enable both Network-EAP and Open with EAP Authentication for the SSID |
EAP-FAST authentication with WPA or WPA2 |
Choose WPA/WPA2/CCKM and EAP-FAST, set EAP-FAST settings, and enable automatic provisioning or import a PAC file |
For WPA, choose a cipher suite that includes TKIP and enable both Network-EAP and Open with EAP Authentication as well as WPA for the SSID For WPA2, choose a cipher suite that includes AES-CCMP and enable both Network-EAP and Open with EAP Authentication as well as WPA for the SSID Note To allow both WPA and non-WPA clients to use the SSID, enable optional WPA. |
EAP-TLS authentication |
If using ADU to configure card |
Choose 802.1x and EAP-TLS; then set EAP-TLS settings |
Set up and enable WEP and enable Open with EAP Authentication for the SSID |
If using Windows XP to configure card |
Choose Enable network access control using IEEE 802.1X and Smart Card or other Certificate as the EAP Type |
Set up and enable WEP and enable Open with EAP Authentication for the SSID |
EAP-TLS authentication with WPA or WPA2 |
If using ADU to configure card |
Choose WPA/WPA2/CCKM and EAP-TLS; then set EAP-TLS settings |
For WPA, choose a cipher suite that includes TKIP; then enable WPA and Open with EAP Authentication for the SSID For WPA2, choose a cipher suite that includes AES-CCMP; then enable WPA and Open with EAP Authentication for the SSID Note To allow both WPA and non-WPA clients to use the SSID, enable optional WPA. |
If using Windows XP to configure card |
Enable WPA and choose Enable network access control using IEEE 802.1X and Smart Card or other Certificate as the EAP Type Note WPA2 is not yet available in the Microsoft Wireless Configuration Manager in Windows XP. |
For WPA, choose a cipher suite that includes TKIP; then enable WPA and Open with EAP Authentication for the SSID Note To allow both WPA and non-WPA clients to use the SSID, enable optional WPA. |
PEAP authentication |
If using ADU to configure card |
Choose 802.1x and PEAP (EAP-GTC) or PEAP (EAP-MSCHAP V2); then set PEAP settings |
Set up and enable WEP and enable Open with EAP Authentication for the SSID |
If using Windows XP to configure card |
Choose Enable network access control using IEEE 802.1X and PEAP as the EAP Type |
Set up and enable WEP and enable Open with EAP Authentication for the SSID |
PEAP authentication with WPA or WPA2 |
If using ADU to configure card |
Choose WPA/WPA2/CCKM and PEAP (EAP-GTC) or PEAP (EAP-MSCHAP V2); then set PEAP settings |
For WPA, choose a cipher suite that includes TKIP; then enable WPA and Open with EAP Authentication for the SSID For WPA2, choose a cipher suite that includes AES-CCMP; then enable WPA and Open with EAP Authentication for the SSID Note To allow both WPA and non-WPA clients to use the SSID, enable optional WPA. |
If using Windows XP to configure card |
Enable WPA and choose Enable network access control using IEEE 802.1X and PEAP as the EAP Type Note WPA2 is not yet available in the Microsoft Wireless Configuration Manager in Windows XP. |
For WPA, choose a cipher suite that includes TKIP; then enable WPA and Open with EAP Authentication for the SSID Note To allow both WPA and non-WPA clients to use the SSID, enable optional WPA. |
CCKM fast secure roaming |
Choose WPA/WPA2/CCKM and LEAP, EAP-FAST, EAP-TLS, PEAP (EAP-GTC), or PEAP (EAP MSCHAP V2); then set the EAP authentication settings Note If you want to enable CCKM, you must choose WPA/WPA2/CCKM, regardless of whether you want the client adapter to use WPA or WPA2. The configuration of the access point to which your client adapter associates determines whether CCKM will be used with 802.1x, WPA, or WPA2. |
Use Cisco IOS Release 12.2(11)JA or later, choose a cipher suite that is compatible with CCKM, enable both Network-EAP and Open with EAP Authentication and CCKM for the SSID, and configure for participation in wireless domain services (WDS) Note To allow both 802.1X clients and non-802.1X clients to use the SSID, enable optional CCKM. |
Reporting access points that fail LEAP authentication |
No settings required; automatically enabled |
No settings required; automatically enabled in the firmware versions listed on page 5-20. |
MIC |
No settings required; automatically enabled |
Set up and enable WEP with full encryption, set MIC to MMH or check the Enable MIC check box, and set Use Aironet Extensions to Yes |
TKIP |
No settings required; automatically enabled |
Set up and enable WEP, set TKIP to Cisco or check the Enable Per Packet Keying check box, and set Use Aironet Extensions to Yes |
Broadcast key rotation |
Enable LEAP, EAP-FAST, EAP-TLS, PEAP (EAP-GTC), or PEAP (EAP-MSCHAP V2) |
Set up and enable WEP and set Broadcast WEP Key Rotation Interval to any value other than zero (0) |
Enabling Static WEP
Follow the steps below to enable static WEP for this profile.
Step 1 Choose Pre-Shared Key (Static WEP) on the Profile Management (Security) window.
Step 2 Click Configure. The Define Pre-Shared Keys window appears (see Figure 5-5).
Figure 5-5 Define Pre-Shared Keys Window
Step 3 Choose one of the following WEP key entry methods:
•Hexadecimal (0-9, A-F)—Specifies that the WEP key will be entered in hexadecimal characters, which include 0-9, A-F, and a-f.
•ASCII Text (all keyboard characters)—Specifies that the WEP key will be entered in ASCII text, which includes alpha characters, numbers, and punctuation marks.
Note ASCII text WEP keys are not supported on the Cisco Aironet 1200 Series Access Points, so you must choose the Hexadecimal (0-9, A-F) option if you are planning to use your client adapter with these access points.
Step 4 For the static WEP key that you are entering (1, 2, 3, or 4), choose a WEP key size of 40 or 128 on the right side of the window. 21AG client adapters can use 40- or 128-bit keys.
Step 5 Obtain the static WEP key from your system administrator and enter it in the blank field for the key you are creating. Follow the guidelines below to enter a new static WEP key:
•WEP keys must contain the following number of characters:
–10 hexadecimal characters or 5 ASCII text characters for 40-bit keys
Example: 5A5A313859 (hexadecimal) or ZZ18Y (ASCII)
–26 hexadecimal characters or 13 ASCII text characters for 128-bit keys
Example: 5A583135333554595549333534 (hexadecimal) or ZX1535TYUI354 (ASCII)
Note You must enter hexadecimal characters if your client adapter will be used with Cisco Aironet 1200 Series Access Points.
•Your client adapter's WEP key must match the WEP key used by the access point (in infrastructure mode) or clients (in ad hoc mode) with which you are planning to communicate.
•When setting more than one WEP key, the keys must be assigned to the same WEP key numbers for all devices. For example, WEP key 2 must be WEP key number 2 on all devices. When multiple WEP keys are set, they must be in the same order on all devices.
Note All existing static WEP keys are displayed as bullets for security reasons. If you need to modify a WEP key, simply click in the WEP key field, delete the bullets, and enter a new key.
Step 6 Click the Transmit Key button to the left of the key you want to use to transmit packets. Only one WEP key can be selected as the transmit key.
Step 7 Click OK to save your settings and return to the Profile Management (Security) window.
Step 8 Perform one of the following to set the Allow Association to Mixed Cells parameter, which indicates whether the client adapter can associate to an access point that allows both WEP and non-WEP associations:
•Check the Allow Association to Mixed Cells check box if the access point to which the client adapter is to associate (or the VLAN to which the client will be assigned) has WEP set to Optional. Otherwise, the client is unable to establish a connection with the access point.
•Uncheck the Allow Association to Mixed Cells check box if the access point to which the client adapter is to associate (or the VLAN to which the client will be assigned) does not have WEP set to Optional. This is the default setting.
Note For security reasons, Cisco recommends that WEP-enabled and WEP-disabled clients not be allowed in the same cell because broadcast packets are sent unencrypted, even to clients running WEP. However, you can enable VLANs on the access point to separate WEP-enabled and WEP-disabled clients.
Step 9 Click OK to save your settings and return to the Cisco Aironet Desktop Utility (Profile Management) window.
Enabling WPA/WPA2 Passphrase
Follow the steps below to enable WPA/WPA2 passphrase (also known as WPA/WPA2 pre-shared key) for this profile.
Note To use WPA passphrase, access points must use Cisco IOS Release 12.2(11)JA or later. To use WPA2 passphrase, access points must use Cisco IOS Release 12.3(2)JA or later.
Step 1 Choose WPA/WPA2 Passphrase on the Profile Management (Security) window.
Step 2 Click Configure. The Define WPA/WPA2 Pre-Shared Key window appears (see Figure 5-6).
Figure 5-6 Define WPA/WPA2 Pre-Shared Key Window
Step 3 Obtain the WPA/WPA2 passphrase for the access point (in an infrastructure network) or other clients (in an ad hoc network) from your system administrator and enter it in the WPA/WPA2 passphrase field. Follow the guidelines below to enter a passphrase:
•WPA/WPA2 passphrases must contain 8 to 63 ASCII text characters or 64 hexadecimal characters.
•Your client adapter's WPA/WPA2 passphrase must match the passphrase used by the access point with which you are planning to communicate.
Step 4 Click OK to save the passphrase and return to the Profile Management (Security) window.
Step 5 If you want to change the value of the Group Policy Delay parameter, enter a new value or use the up and down arrows to select a value between 0 and 65535 seconds. (Microsoft supports only values between 30 and 600 seconds. The default value is 60 seconds.)
The Group Policy Delay parameter specifies how much time elapses before the Windows logon process starts Group Policy, a Windows feature used by administrators to specify configuration options for groups of users. The objective is to delay the start of Group Policy until wireless network authentication occurs. The value that you set for this parameter goes into effect after the computer reboots with this profile set as the active profile.
Note A Microsoft hot fix is required in order to use this parameter on computers running Windows 2000. Refer to the "Installing a Microsoft Hot Fix for Group Policy Delay" section for information on obtaining and installing the hot fix.
Step 6 Click OK to save your settings and return to the Cisco Aironet Desktop Utility (Profile Management) window.
Enabling LEAP
Before you can enable LEAP authentication, your network devices must meet the following requirements:
•Access points to which your client adapter may attempt to authenticate must use the following firmware versions or later: 11.23T (access points running VxWorks), Cisco IOS Release 12.2(4)JA (1100 series access points), Cisco IOS Release 12.2(8)JA (1200 series access points), Cisco IOS Release 12.3(4)JA (1130 series and BR 1310 series access points), Cisco IOS Release 12.3(7)JA (1240 series access points), or Cisco IOS Release 12.2(13)JA (350 series access points).
Note To use WPA or CCKM, access points must use Cisco IOS Release 12.2(11)JA or later. To use WPA2, access points must use Cisco IOS Release 12.3(2)JA or later. To use the Reporting Access Points That Fail LEAP Authentication feature, access points must use the firmware versions listed on page 5-22.
•All necessary infrastructure devices (such as access points, servers, etc.) must be properly configured for LEAP authentication.
Follow the steps below to enable LEAP authentication for this profile.
Step 1 Perform one of the following on the Profile Management (Security) window:
•If you want to enable LEAP without WPA or WPA2, choose 802.1x under Set Security Options and LEAP in the 802.1x EAP Type drop-down box.
•If you want to enable LEAP with WPA or WPA2, choose WPA/WPA2/CCKM under Set Security Options and LEAP in the WPA/WPA2/CCKM EAP Type drop-down box.
Note If you want to enable CCKM on the client adapter, you must choose the WPA/WPA2/CCKM security option, regardless of whether you want the adapter to use WPA or WPA2. The configuration of the access point to which your client adapter associates determines whether CCKM will be used with 802.1x, WPA, or WPA2.
Note Refer to the "WPA and WPA2" section for additional information.
Step 2 Click Configure. The Configure LEAP window appears (see Figure 5-7).
Figure 5-7 Configure LEAP Window
Step 3 Choose one of the following LEAP username and password setting options:
•Use Temporary User Name and Password—Requires you to enter the LEAP username and password each time the computer reboots in order to authenticate and gain access to the network, unless you choose Use Windows User Name and Password.
•Use Saved User Name and Password—Does not require you to enter a LEAP username and password each time the computer reboots. Authentication occurs automatically as needed using a saved username and password (which are registered with the RADIUS server).
Step 4 Perform one of the following:
•If you chose Use Temporary User Name and Password in Step 3, choose one of the following options:
–Use Windows User Name and Password—Causes your Windows username and password to also serve as your LEAP username and password, giving you only one set of credentials to remember. After you log in, the LEAP authentication process begins automatically. This option is the default setting.
–Automatically Prompt for User Name and Password—Requires you to enter a separate LEAP username and password (which are registered with the RADIUS server) in addition to your regular Windows login in order to start the LEAP authentication process.
–Manually Prompt for User Name and Password—Requires you to manually invoke the LEAP authentication process as needed using the Manual Login option in the Action drop-down menu or ASTU. You are not prompted to enter a LEAP username and password during the Windows login. This option might be used to support a software token one-time password system or other systems that require additional software that is not available at login.
•If you chose Use Saved User Name and Password in Step 3, follow these steps:
a. Enter a username and password in the appropriate fields.
b. Re-enter the password in the Confirm Password field.
c. If you wish to specify a domain name that will be passed to the RADIUS server along with your username, enter it in the Domain field.
Step 5 If you chose Automatically Prompt for User Name and Password or Manually Prompt for User Name and Password in Step 4, perform one of the following:
•Check the Always Resume the Secure Session check box at the top of the window if you want the LEAP supplicant to always attempt to resume the previous session without prompting you to re-enter your credentials whenever the client adapter becomes disassociated. The session resumes after the client temporarily loses connection to the access point (such as by roaming in and out of range) or wakes up from suspend or hibernate mode. This is the default setting.
•Uncheck the Always Resume the Secure Session check box if you want to be prompted to re-enter your LEAP username and password whenever your client adapter temporarily loses association by roaming out of range or wakes up from suspend or hibernate mode.
Note Checking this check box gives you the convenience of not having to re-enter your username and password when your client adapter experiences momentary losses of association. However, if you leave your device unattended during the period of time when the LEAP session can be resumed without re-entering user credentials, be aware that someone can resume your LEAP session and access the network.
Note The Always Resume the Secure Session check box is disabled if you chose Use Windows User Name and Password or Use Saved User Name and Password in Step 4.
Step 6 If you work in an environment with multiple domains and therefore want your Windows login domain to be passed to the RADIUS server along with your username, check the Include Windows Logon Domain with User Name check box. The default setting is checked.
Note If you chose to use a saved username and password, the Include Windows Logon Domain with User Name check box is grayed out and the saved domain name is passed to the RADIUS server.
Step 7 If you want to force the client adapter to disassociate after you log off so that another user cannot gain access to the wireless network using your credentials, check the No Network Connection Unless User Is Logged In check box. The default setting is checked.
Step 8 In the Authentication Timeout Value field, choose the amount of time (in seconds) before a LEAP authentication attempt is considered to be failed and an error message appears.
Range: 30 to 300 seconds
Default: 90 seconds
Step 9 Click OK to save your settings and return to the Profile Management (Security) window.
Step 10 Perform one of the following to set the Allow Association to Mixed Cells parameter, which indicates whether the client adapter can associate to an access point that allows both WEP and non-WEP associations:
•Check the Allow Association to Mixed Cells check box if the access point to which the client adapter is to associate (or the VLAN to which the client will be assigned) has WEP set to Optional. Otherwise, the client is unable to establish a connection with the access point.
•Uncheck the Allow Association to Mixed Cells check box if the access point to which the client adapter is to associate (or the VLAN to which the client will be assigned) does not have WEP set to Optional. This is the default setting.
Note This parameter is available only if the 802.1x security option is selected.
Note For security reasons, Cisco recommends that WEP-enabled and WEP-disabled clients not be allowed in the same cell because broadcast packets are sent unencrypted, even to clients running WEP. However, you can enable VLANs on the access point to separate WEP-enabled and WEP-disabled clients.
Step 11 If you want to limit the amount of time that is spent searching for a domain controller during the authentication process, check the Limit Time for Finding Domain Controller To check box. Then in the edit box, enter the amount of time (in seconds) to which you want to limit the search for the domain controller. A timeout value of 0 causes the authentication process to bypass the "Finding Domain Controller" step altogether.
Range of timeout value: 0 to 300 seconds
Default: Unchecked; 0 seconds
Note When the "Finding Domain Controller" step is reached during the authentication process, a timer starts based on the number of seconds you specified for finding the domain controller. If either this value or the LEAP authentication timeout value expires before the domain controller is found, the authentication process times out. For example, if the authentication timeout value is 60 seconds and the finding domain controller timeout value is 10 seconds, the client adapter has up to 60 seconds to complete the entire authentication process, up to 10 seconds of which is allocated for finding the domain controller. However, if authentication happens quickly, the software might reach the "Finding Domain Controller" step in 5 seconds. If the domain controller could not be found within 10 seconds, the authentication process would time out in just 15 seconds.
Note The finding domain controller timeout value can never extend the authentication process beyond the LEAP authentication timeout value, even if the finding domain controller timeout value is greater than the LEAP authentication timeout value.
Note If you require domain services such as login scripts and roaming desktops, Cisco recommends that you uncheck the Limit Time for Finding Domain Controller To check box.
Note Regardless of whether the check box is checked or unchecked, the "Finding Domain Controller" step is bypassed once you are logged into Windows or if you log into the local machine and not into a domain.
Step 12 If you want to change the value of the Group Policy Delay parameter, enter a new value or use the up and down arrows to select a value between 0 and 65535 seconds. (Microsoft supports only values between 30 and 600 seconds. The default value is 60 seconds.)
The Group Policy Delay parameter specifies how much time elapses before the Windows logon process starts Group Policy, a Windows feature used by administrators to specify configuration options for groups of users. The objective is to delay the start of Group Policy until wireless network authentication occurs. The value that you set for this parameter goes into effect after the computer reboots with this profile set as the active profile.
Note A Microsoft hot fix is required in order to use this parameter on computers running Windows 2000. Refer to the "Installing a Microsoft Hot Fix for Group Policy Delay" section for information on obtaining and installing the hot fix.
Step 13 Click OK to save your settings and return to the Cisco Aironet Desktop Utility (Profile Management) window.
Step 14 Refer to Chapter 6, for instructions on authenticating using LEAP.
Enabling EAP-FAST
Before you can enable EAP-FAST authentication, your network devices must meet the following requirements:
•Access points to which your client adapter may attempt to authenticate must use the following firmware versions or later: 11.23T (340 and 350 series access points), 11.54T (1200 series access points), Cisco IOS Release 12.3(4)JA (1130 series and BR 1310 series access points), Cisco IOS Release 12.3(7)JA (1240 series access points), or Cisco IOS Release 12.2(4)JA (1100 series access points).
Note To use WPA or CCKM, access points must use Cisco IOS Release 12.2(11)JA or later. To use WPA2, access points must use Cisco IOS Release 12.3(2)JA or later. To use the Reporting Access Points That Fail LEAP or EAP-FAST Authentication feature, access points must use the firmware versions listed on page 5-20.
Note The access point to which your client adapter will associate must be configured for open authentication.
•All necessary infrastructure devices (such as access points, servers, gateways and user databases) must be properly configured for EAP-FAST authentication.
Follow these steps to enable EAP-FAST authentication for this profile.
Step 1 Perform one of the following on the Profile Management (Security) window:
•If you want to enable EAP-FAST without WPA or WPA2, choose 802.1x under Set Security Options and EAP-FAST in the 802.1x EAP Type drop-down box.
•If you want to enable EAP-FAST with WPA or WPA2, choose WPA/WPA2/CCKM under Set Security Options and EAP-FAST in the WPA/WPA2/CCKM EAP Type drop-down box.
Note If you want to enable CCKM on the client adapter, you must choose the WPA/WPA2/CCKM security option, regardless of whether you want the adapter to use WPA or WPA2. The configuration of the access point to which your client adapter associates determines whether CCKM will be used with 802.1x, WPA, or WPA2.
Note Refer to the "WPA and WPA2" section for additional information.
Step 2 Click Configure. The Configure EAP-FAST window appears (see Figure 5-8).
Figure 5-8 Configure EAP-FAST Window
Step 3 Choose an authentication method from the EAP-FAST Authentication Method drop-down list and click Configure.
Step 4 If you chose GTC Token/Password in Step 3, do the following in the Configure GTC Token/Password window (see Figure 5-9):
Figure 5-9 Configure GTC Token/Password Window
1. Check the Always Resume the Secure Session check box at the top of the window if you want the EAP-FAST supplicant to always attempt to resume the previous session without prompting you to re-enter your credentials whenever the client adapter becomes disassociated. The session resumes after the client temporarily loses connection to the access point (such as by roaming in and out of coverage) or wakes up from suspend or hibernate mode. This is the default setting.
Uncheck the Always Resume the Secure Session check box if you want to be prompted to re-enter your EAP-FAST username and password whenever your client adapter temporarily loses association by roaming out of coverage or wakes up from suspend or hibernate mode.
Note Checking this check box gives you the convenience of not having to re-enter your username and password when your client adapter experiences momentary losses of association. However, if you leave your device unattended during the period of time when the EAP-FAST session can be resumed without re-entering user credentials, be aware that someone can resume your EAP-FAST session and access the network.
Note The Always Resume the Secure Session check box is disabled if you chose Static Password.
2. Check the Validate Server Identity check box to force the system to validate the identity of the server as an added level of security.
If you uncheck this box, only user credentials will be validated.
3. To configure the remaining options in this window, refer to "Enabling PEAP (EAP-GTC)" section.
4. Click OK to save your settings and return to the Configure EAP-FAST window.
Step 5 If you chose MSCHAPv2 User Name and Password in Step 3, do the following in the Configure MSCHAPv2 User Name and Password window (see Figure 5-10):
Figure 5-10 Configure MSCHAPv2 User Name and Password Window
1. Check the Always Resume the Secure Session check box at the top of the window if you want the EAP-FAST supplicant to always attempt to resume the previous session without prompting you to re-enter your credentials whenever the client adapter becomes disassociated. The session resumes after the client temporarily loses connection to the access point (such as by roaming in and out of coverage) or wakes up from suspend or hibernate mode. This is the default setting.
Uncheck the Always Resume the Secure Session check box if you want to be prompted to re-enter your EAP-FAST username and password whenever your client adapter temporarily loses association by roaming out of coverage or wakes up from suspend or hibernate mode.
Note To check or uncheck the Always Resume the Secure Session check box, you must first choose Automatically Prompt for User Name and Password or Manually Prompt for User Name and Password under Use Temporary User Name and Password.
2. Check the Validate Server Identity check box to force the system to validate the identity of the server as an added level of security.
3. Choose a certificate authority from which the server certificate was downloaded in the Trusted Root Certification Authorities drop-down box, or, if applicable, choose <Any>.
4. To use a temporary username and password, choose Use Temporary User Name and Password.
This option requires you to enter the EAP-FAST username and password each time the computer reboots in order to authenticate and gain access to the network, unless you choose Use Windows User Name and Password.
Choose one of the following options under Use Temporary User Name and Password:
–Use Windows User Name and Password—Causes your Windows username and password to also serve as your EAP-FAST username and password, giving you only one set of credentials to remember. After you log in, the authentication process begins automatically. This option is the default setting.
–Automatically Prompt for User Name and Password—Requires you to enter a separate EAP-FAST username and password (which are registered with the RADIUS server) in addition to your regular Windows login in order to start the authentication process.
–Manually Prompt for User Name and Password—Requires you to manually invoke the EAP-FAST authentication process as needed using the Manual Login option in the Action drop-down menu or ASTU. You are not prompted to enter an EAP-FAST username and password during the Windows login. This option might be used to support a software token one-time password system or other systems that require additional software that is not available at login.
5. To use a saved username and password, choose Use Saved User Name and Password.
This option does not require you to enter an EAP-FAST username and password each time the computer reboots. Authentication occurs automatically as needed using a saved username and password (which are registered with the RADIUS server).
Follow these steps to specify the username and password to use for EAP-FAST authentication:
a. Enter a username and password in the appropriate fields.
b. Re-enter the password in the Confirm Password field.
c. If you wish to specify a domain name that will be passed to the RADIUS server along with your username, enter it in the Domain field.
6. If you work in an environment with multiple domains and therefore want your Windows login domain to be passed to the RADIUS server along with your username, check the Include Windows Logon Domain with User Name check box. The default setting is checked.
Note If you chose to use a saved username and password but do not check the Include Windows Logon Domain with User Name check box, the saved domain name is not passed to the RADIUS server.
7. To specify a server or domain name and a login name to use for authenticating user credentials, click Advanced and follow the instructions in "Configuring Advanced Settings" section.
8. Click OK to save your settings and return to the Configure EAP-FAST window.
Step 6 If you chose TLS Client Certificate in Step 3, refer to "Enabling EAP-TLS" section (Step 5 to Step 10) to configure the options in the Configure TLS Client Certificate window (Figure 5-11).
Figure 5-11 Configure TLS Client Certificate Window
Step 7 In the Select One or More PAC Authorities list, select the PAC authorities and PAC authority groups that are associated with the network defined by the profile's SSID. The list contains the names of all the authentication servers from which you have previously provisioned a PAC.
If the Select One or More PAC Authorities list is empty or does not contain the name of a desired PAC authority, go to Step 8 to import a PAC file.
Note This step is required for manual PAC provisioning but optional for automatic PAC provisioning. If automatic provisioning is enabled, automatic provisioning will be initiated during the authentication process of the EAP-FAST profile if no PAC authority was selected, the PAC could not be found, or the specified PAC does not match the server ID.
Step 8 If necessary, follow these steps to import or modify the grouping of PAC files:
a. Click Manage. The Manage PACs window appears (see Figure 5-12).
Figure 5-12 Manage PACs Window
b. To create a new group, click New Group.
c. To move a PAC from one group to another, just drag it to the destination group.
d. Click Import. The Import EAP-FAST PAC File window appears (see Figure 5-13).
Figure 5-13 Import EAP-FAST PAC File Window
e. Find the location of the PAC file (*.pac) in the Look in box. The default location is C:\Program Files\Cisco Aironet.
Note The filename and extension of a PAC file is determined by the PAC authority that issues it, but the standard file extension is pac.
f. Choose one of these PAC store options to determine where the imported PAC file will be stored and to whom it will be accessible:
•Global—PACs that are stored in the global PAC store can be accessed and used by any user at any logon stage. Global PACs are available before or during logon or after the user is logged off if the profile is not configured with the No Network Connection Unless User Is Logged In option.
•Private—PACs that are stored in the private store can be accessed and used only by the user who provisioned them or the system administrator. They are not accessible until the user is logged onto the local system. This is the default option.
g. Click Import.
h. If the Enter Password window appears (see Figure 5-14), enter the PAC file password, which can be obtained from your system administrator, and click OK.
Figure 5-14 Enter Password Window
Note PAC file passwords are optional. The PAC authority determines whether to issue PAC files that require user-supplied passwords. Nevertheless, all PAC files (even those without passwords) are encrypted and protected. PAC file passwords are different from EAP-FAST passwords and need to be entered only once, at the time a PAC is imported.
i. If you try to import a PAC file with the same PAC ID as a previously imported PAC file, you are asked if you want to update the existing PAC. If you click Yes, the existing PAC is replaced by the new one from the imported file.
j. If the PAC file was imported successfully, the following message appears: "The EAP-FAST PAC file was imported and is ready for use." Click OK to return to the Manage PACs window.
k. The imported PAC now appears in the PAC tree on the Manage PACs window.
l. To delete a group or manually provisioned PAC file from storage, select the item and click Delete. When a message appears asking you to confirm your decision, click Yes. The PAC file is removed from the tree.
m. Click Close to return to the Configure EAP-FAST window.
n. The name of the PAC authority that issued the PAC now appears in the PAC authority list on the Configure EAP-FAST window. Select the desired PAC authorities or groups from the list.
Step 9 Check the Use Any PAC Belonging to the Same Group check box to use any PAC authority in the selected groups for PAC provisioning.
Step 10 Perform one of the following to configure PAC provisioning:
•If you want to enable automatic PAC provisioning, make sure the Allow Automatic PAC Provisioning check box is checked. A protected access credentials (PAC) is automatically obtained as needed (for example, when a PAC expires, when the client adapter accesses a different server or when the EAP-FAST username cannot be matched to a previously provisioned PAC).
•If you want to enable manual PAC provisioning, uncheck the Allow Automatic PAC Provisioning check box. This option requires you to choose a PAC authority or manually import a PAC file.
Note LDAP user databases support only manual PAC provisioning while Cisco Secure ACS internal, Cisco Secure ODBC, and Windows NT/2000/2003 domain user databases support both automatic and manual PAC provisioning.
Note Provisioning occurs only upon initial negotiation of the PAC or upon PAC expiration. After the PAC is provisioned, it serves as the per-user key by which authentication transactions are secured.
Step 11 Check the Use Machine Information for Domain Logon check box if you want the client to attempt to log into a domain using machine authentication with a machine certificate and machine credentials rather than user authentication. Doing so enables your computer to connect to the network prior to user logon. The default setting is unchecked.
Note If you do not check the Use Machine Information for Domain Logon check box, machine authentication is not performed. Authentication does not occur until you log on.
Step 12 If you want to force the client adapter to disassociate after you log off so that another user cannot gain access to the wireless network using your credentials, check the No Network Connection Unless User Is Logged In check box. The default setting is checked.
Step 13 Click OK to save your settings and return to the Profile Management (Security) window.
Note If you selected a private PAC and the No Network Connection Unless User Is Logged In check box is unchecked, a message appears indicating that the PAC may not be accessible during the domain logon process or when you are logged off. If you want a copy of the PAC to be added to the global store so that it will be available when you are not logged on, click Yes. If you do not want a copy of the PAC to be added to the global store, click No; then click OK when a message appears indicating that you may need to later reconfigure your profile to use a global PAC if you experience wireless connection problems during domain logon or when you are not logged on.
Step 14 Perform one of the following to set the Allow Association to Mixed Cells parameter, which indicates whether the client adapter can associate to an access point that allows both WEP and non-WEP associations:
•Check the Allow Association to Mixed Cells check box if the access point to which the client adapter is to associate (or the VLAN to which the client will be assigned) has WEP set to Optional. Otherwise, the client is unable to establish a connection with the access point.
•Uncheck the Allow Association to Mixed Cells check box if the access point to which the client adapter is to associate (or the VLAN to which the client will be assigned) does not have WEP set to Optional. This is the default setting.
Note This parameter is available only if the 802.1x security option is selected.
Note For security reasons, Cisco recommends that WEP-enabled and WEP-disabled clients not be allowed in the same cell because broadcast packets are sent unencrypted, even to clients running WEP. However, you can enable VLANs on the access point to separate WEP-enabled and WEP-disabled clients.
Step 15 If you want to limit the amount of time that is spent searching for a domain controller during the authentication process, check the Limit Time for Finding Domain Controller To check box. Then in the edit box, enter the amount of time (in seconds) to which you want to limit the search for the domain controller. A timeout value of 0 causes the authentication process to bypass the "Finding Domain Controller" step altogether.
Range of timeout value: 0 to 300 seconds
Default: Unchecked; 0 seconds
Note When the "Finding Domain Controller" step is reached during the authentication process, a timer starts based on the number of seconds you specified for finding the domain controller. If either this value or the EAP-FAST authentication timeout value expires before the domain controller is found, the authentication process times out. For example, if the authentication timeout value is 60 seconds and the finding domain controller timeout value is 10 seconds, the client adapter has up to 60 seconds to complete the entire authentication process, up to 10 seconds of which is allocated for finding the domain controller. However, if authentication happens quickly, the software might reach the "Finding Domain Controller" step in 5 seconds. If the domain controller could not be found within 10 seconds, the authentication process would timeout in just 15 seconds.
Note The finding domain controller timeout value can never extend the authentication process beyond the EAP-FAST authentication timeout value, even if the finding domain controller timeout value is greater than the EAP-FAST authentication timeout value.
Note If you require domain services such as login scripts and roaming desktops, Cisco recommends that you uncheck the Limit Time for Finding Domain Controller To check box.
Note Regardless of whether the check box is checked or unchecked, the "Finding Domain Controller" step is bypassed once you are logged into Windows or if you log into the local machine and not into a domain.
Step 16 If you want to change the value of the Group Policy Delay parameter, enter a new value or use the up and down arrows to select a value between 0 and 65535 seconds. (Microsoft supports only values between 30 and 600 seconds. The default value is 60 seconds.)
The Group Policy Delay parameter specifies how much time elapses before the Windows logon process starts Group Policy, a Windows feature used by administrators to specify configuration options for groups of users. The objective is to delay the start of Group Policy until wireless network authentication occurs. The value that you set for this parameter goes into effect after the computer reboots with this profile set as the active profile.
Note A Microsoft hot fix is required in order to use this parameter on computers running Windows 2000. Refer to the "Installing a Microsoft Hot Fix for Group Policy Delay" section for information on obtaining and installing the hot fix.
Step 17 Click OK to save your settings and return to the Cisco Aironet Desktop Utility (Profile Management) window.
Step 18 Refer to Chapter 6, for instructions on authenticating using EAP-FAST.
Enabling EAP-TLS or PEAP
Before you can enable EAP-TLS or PEAP authentication, your network devices must meet the following requirements:
•You must have a valid Windows username and password, and the password cannot be blank.
•The appropriate certificates must be installed on your computer. EAP-TLS requires both a Certificate Authority (CA) certificate and a user certificate while PEAP requires only a CA certificate.
Note Contact your system administrator if you need help obtaining and importing the necessary certificates.
•To support EAP-TLS machine authentication with machine credentials:
–A machine certificate must be obtained from the server, and client machine access must be enabled on the server.
–Permissions for the MachineKeys folder, which stores the certificate pair keys for both the computer and users, must be set correctly. Refer to Microsoft knowledgebase article Q278381 for information on correctly setting up folder permissions:
http://support.microsoft.com/default.aspx?scid=kb;en-us;Q278381
Note If you ever change permissions on higher-level directories and those settings are applied to all subdirectories, you may need to reset the permissions for the MachineKeys folder.
•Access points to which your client adapter may attempt to authenticate must use the following firmware versions or later: 12.00T (access points running VxWorks), Cisco IOS Release 12.2(4)JA (1100 series access points), Cisco IOS Release 12.2(8)JA (1200 series access points), Cisco IOS Release 12.3(4)JA (1130 series and BR 1310 series access points), Cisco IOS Release 12.3(7)JA (1240 series access points), or Cisco IOS Release 12.2(13)JA (350 series access points).
Note To use WPA or CCKM, access points must use Cisco IOS Release 12.2(11)JA or later. To use WPA2, access points must use Cisco IOS Release 12.3(2)JA or later.
•All necessary infrastructure devices (such as access points, servers, gateways, user databases, etc.) must be properly configured for the authentication type you plan to enable on the client.
Follow the instructions in one of the sections below to enable EAP-TLS or PEAP authentication for this profile:
•Enabling EAP-TLS, page 45
•Enabling PEAP (EAP-GTC), page 48
•Enabling PEAP (EAP-MSCHAP V2), page 52
•Enabling PEAP (EAP-MSCHAP V2) machine authentication with machine certificates, page 55
Enabling EAP-TLS
Follow the steps below to enable EAP-TLS authentication for this profile.
Step 1 Perform one of the following on the Profile Management (Security) window:
•If you want to enable EAP-TLS without WPA or WPA2, choose 802.1x under Set Security Options and EAP-TLS in the 802.1x EAP Type drop-down box.
•If you want to enable EAP-TLS with WPA or WPA2, choose WPA/WPA2/CCKM under Set Security Options and EAP-TLS in the WPA/WPA2/CCKM EAP Type drop-down box.
Note If you want to enable CCKM on the client adapter, you must choose the WPA/WPA2/CCKM security option, regardless of whether you want the adapter to use WPA or WPA2. The configuration of the access point to which your client adapter associates determines whether CCKM will be used with 802.1x, WPA, or WPA2.
Note Refer to the "WPA and WPA2" section for additional information.
Step 2 Click Configure. The Configure EAP-TLS window appears (see Figure 5-15).
Figure 5-15 Configure EAP-TLS Window
Step 3 Check the Use Machine Information for Domain Logon check box if you want the client to attempt to log into a domain using machine authentication with a machine certificate and machine credentials rather than user authentication. Doing so enables your computer to connect to the network prior to user logon. The default setting is unchecked.
Note If you do not check the Use Machine Information for Domain Logon check box, machine authentication is not performed. Authentication does not occur until you log on.
Step 4 If you checked the Use Machine Information For Domain Logon check box in the previous step, the Always Do User Authentication check box at the bottom of the window becomes active. Perform one of the following:
•Check the Always Do User Authentication check box if you want the client to switch from using machine authentication to using user authentication after you log on using your username and password. This is the default setting.
•Uncheck the Always Do User Authentication check box if you want the client to continue to use machine authentication after your computer logs into the domain.
Step 5 Check the Validate Server Identity check box to force the system to validate the identity of the server as an added level of security. If you uncheck this box, only user credentials will be validated.
Step 6 Choose the certificate authority from which the server certificate was downloaded in the Trusted Root Certification Authorities drop-down box.
Step 7 Choose your server certificate in the Select a Certificate drop-down box.
Step 8 Perform one of the following:
•Leave the Server/Domain Name field blank to allow the client to accept a certificate from any server that supplies a certificate signed by the certificate authority listed in the Trusted Root Certification Authorities drop-down box. This is the recommended option.
•In the Server/Domain Name field, enter the domain name of the server from which the client will accept a certificate.
Step 9 If the Login Name field is not filled in automatically, enter your username in this format: username@domain (for example, jsmith@acs-test.cisco.com).
Step 10 Click OK to save your settings and return to the Profile Management (Security) window.
Step 11 Perform one of the following to set the Allow Association to Mixed Cells parameter, which indicates whether the client adapter can associate to an access point that allows both WEP and non-WEP associations:
•Check the Allow Association to Mixed Cells check box if the access point to which the client adapter is to associate (or the VLAN to which the client will be assigned) has WEP set to Optional. Otherwise, the client is unable to establish a connection with the access point.
•Uncheck the Allow Association to Mixed Cells check box if the access point to which the client adapter is to associate (or the VLAN to which the client will be assigned) does not have WEP set to Optional. This is the default setting.
Note This parameter is available only if the 802.1x security option is selected.
Note For security reasons, Cisco recommends that WEP-enabled and WEP-disabled clients not be allowed in the same cell because broadcast packets are sent unencrypted, even to clients running WEP. However, you can enable VLANs on the access point to separate WEP-enabled and WEP-disabled clients.
Step 12 If you want to change the value of the Group Policy Delay parameter, enter a new value or use the up and down arrows to select a value between 0 and 65535 seconds. (Microsoft supports only values between 30 and 600 seconds. The default value is 60 seconds.)
The Group Policy Delay parameter specifies how much time elapses before the Windows logon process starts Group Policy, a Windows feature used by administrators to specify configuration options for groups of users. The objective is to delay the start of Group Policy until wireless network authentication occurs. The value that you set for this parameter goes into effect after the computer reboots with this profile set as the active profile.
Note A Microsoft hot fix is required in order to use this parameter on computers running Windows 2000. Refer to the "Installing a Microsoft Hot Fix for Group Policy Delay" section for information on obtaining and installing the hot fix.
Step 13 Click OK to save your settings and return to the Cisco Aironet Desktop Utility (Profile Management) window.
Step 14 Refer to Chapter 6, for instructions on authenticating using EAP-TLS.
Enabling PEAP (EAP-GTC)
Follow these steps to enable PEAP (EAP-GTC) authentication for this profile.
Step 1 Perform one of the following:
•If you want to enable PEAP (EAP-GTC) without WPA or WPA2, choose 802.1x under Set Security Options and PEAP (EAP-GTC) in the 802.1x EAP Type drop-down box.
•If you want to enable PEAP (EAP-GTC) with WPA or WPA2, choose WPA/WPA2/CCKM under Set Security Options and PEAP (EAP-GTC) in the WPA/WPA2/CCKM EAP Type drop-down box.
Note If you want to enable CCKM on the client adapter, you must choose the WPA/WPA2/CCKM security option, regardless of whether you want the adapter to use WPA or WPA2. The configuration of the access point to which your client adapter associates determines whether CCKM will be used with 802.1x, WPA, or WPA2.
Note Refer to the "WPA and WPA2" section for additional information.
Step 2 Click Configure. The Configure PEAP (EAP-GTC) window appears (see Figure 5-16).
Figure 5-16 Configure PEAP (EAP-GTC) Window
Step 3 Check the Use Machine Information for Domain Logon check box if you want the client to attempt to log into a domain using machine authentication with user credentials rather than user authentication. Doing so enables your computer to connect to the network prior to user logon. The default setting is checked.
Note If you do not check the Use Machine Information for Domain Logon check box, machine authentication is not performed. Authentication does not occur until you log on.
Step 4 Check the Validate Server Identity check box to force the system to validate the identity of the server as an added level of security. If you uncheck this box, only user credentials will be validated.
Step 5 Choose the certificate authority from which the server certificate was downloaded in the Trusted Root Certification Authorities drop-down box, or, if applicable, choose <Any>.
Step 6 Choose either Token or Static Password, depending on your user database.
Note If you choose Token, you must use a hardware token device or the Secure Computing SofToken program (release 2.1 or later) to obtain the one-time password and enter the password when prompted during the authentication process. Secure Computing PremierAccess release 3.1.1 or later is the only supported token server.
Step 7 If you chose Token in Step 6, perform one of the following:
•Check the Always Resume the Secure Session check box at the top of the window if you want the PEAP (EAP-GTC) supplicant to always attempt to resume the previous session without prompting you to re-enter your credentials whenever the client adapter becomes disassociated. The session resumes after the client temporarily loses connection to the access point (such as by roaming in and out of coverage) or wakes up from suspend or hibernate mode. This is the default setting.
•Uncheck the Always Resume the Secure Session check box if you want to be prompted to re-enter your PEAP (EAP-GTC) username and password whenever your client adapter temporarily loses association by roaming out of coverage or wakes up from suspend or hibernate mode.
Note Checking this check box gives you the convenience of not having to re-enter your username and password when your client adapter experiences momentary losses of association. However, if you leave your device unattended during the period of time when the PEAP (EAP-GTC) session can be resumed without re-entering user credentials, be aware that someone can resume your PEAP (EAP-GTC) session and access the network.
Note The Always Resume the Secure Session check box is disabled if you chose Static Password in Step 6.
Step 8 Perform one of the following to specify the username that will be used for inner PEAP tunnel authentication:
•If you want your Windows username to also serve as your PEAP username, check the Use Windows User Name check box. This option gives you only one username to remember.
Note If you chose the Static Password option in Step 6, the check box reads Use Windows User Name and Password.
•If you want to enter a separate PEAP username (which is registered with the RADIUS server) in addition to your regular Windows username in order to start the PEAP authentication process, enter your PEAP username in the User Name field.
Note Your Windows username is filled in automatically. Simply delete your Windows username and enter your separate PEAP username.
Step 9 If you entered a PEAP username in the previous step and chose the Static Password option in Step 6, enter your PEAP authentication password (which is registered with the RADIUS server) in both the Password and Confirm Password fields.
Step 10 If the Use Windows User Name and Password check box is unchecked and you want to implement added security by further refining the network certificate that will be accepted and controlling the string used to set up the outer PEAP tunnel, follow the steps in "Configuring Advanced Settings" section.
Step 11 Click OK to save your settings and return to the Profile Management (Security) window.
Step 12 Perform one of the following to set the Allow Association to Mixed Cells parameter, which indicates whether the client adapter can associate to an access point that allows both WEP and non-WEP associations:
•Check the Allow Association to Mixed Cells check box if the access point to which the client adapter is to associate (or the VLAN to which the client will be assigned) has WEP set to Optional. Otherwise, the client is unable to establish a connection with the access point.
•Uncheck the Allow Association to Mixed Cells check box if the access point to which the client adapter is to associate (or the VLAN to which the client will be assigned) does not have WEP set to Optional. This is the default setting.
Note This parameter is available only if the 802.1x security option is selected.
Note For security reasons, Cisco recommends that WEP-enabled and WEP-disabled clients not be allowed in the same cell because broadcast packets are sent unencrypted, even to clients running WEP. However, you can enable VLANs on the access point to separate WEP-enabled and WEP-disabled clients.
Step 13 If you want to change the value of the Group Policy Delay parameter, enter a new value or use the up and down arrows to select a value between 0 and 65535 seconds. (Microsoft supports only values between 30 and 600 seconds. The default value is 60 seconds.)
The Group Policy Delay parameter specifies how much time elapses before the Windows logon process starts Group Policy, a Windows feature used by administrators to specify configuration options for groups of users. The objective is to delay the start of Group Policy until wireless network authentication occurs. The value that you set for this parameter goes into effect after the computer reboots with this profile set as the active profile.
Note A Microsoft hot fix is required in order to use this parameter on computers running Windows 2000. Refer to the "Installing a Microsoft Hot Fix for Group Policy Delay" section for information on obtaining and installing the hot fix.
Step 14 Click OK to save your settings and return to the Cisco Aironet Desktop Utility (Profile Management) window.
Step 15 Refer to Chapter 6, for instructions on authenticating using PEAP (EAP-GTC).
Enabling PEAP (EAP-MSCHAP V2)
Follow the steps below to enable PEAP (EAP-MSCHAP V2) for this profile.
Step 1 Perform one of the following:
•If you want to enable PEAP (EAP-MSCHAP V2) without WPA or WPA2, choose 802.1x under Set Security Options and PEAP (EAP-MSCHAP V2) in the 802.1x EAP Type drop-down box.
•If you want to enable PEAP (EAP-MSCHAP V2) with WPA or WPA2, choose WPA/WPA2/CCKM under Set Security Options and PEAP (EAP-MSCHAP V2) in the WPA/WPA2/CCKM EAP Type drop-down box.
Note If you want to enable CCKM on the client adapter, you must choose the WPA/WPA2/CCKM security option, regardless of whether you want the adapter to use WPA or WPA2. The configuration of the access point to which your client adapter associates determines whether CCKM will be used with 802.1x, WPA, or WPA2.
Note Refer to the "WPA and WPA2" section for additional information.
Step 2 Click Configure. The Configure PEAP (EAP-MSCHAP V2) window appears (see Figure 5-17).
Figure 5-17 Configure PEAP (EAP-MSCHAP V2) Window
Step 3 Check the Use Machine Information for Domain Logon check box if you want the client to attempt to log into a domain using machine authentication with user credentials rather than user authentication. Doing so enables your computer to connect to the network prior to user logon. The default setting is checked.
Note If you do not check the Use Machine Information for Domain Logon check box, machine authentication is not performed. Authentication does not occur until you log on.
Step 4 Check the Validate Server Identity check box to force the system to validate the identity of the server as an added level of security. If you uncheck this box, only user credentials will be validated.
Step 5 Choose the certificate authority from which the server certificate was downloaded in the Trusted Root Certification Authorities drop-down box, or, if applicable, choose <Any>.
Step 6 Perform one of the following to specify how you want to establish a network connection:
•If you want to connect using a username and password, choose User Name and Password and go to Step 7.
•If you want to connect using a user certificate installed on your computer, choose Certificate, select a certificate from the drop-down box, and go to Step 8.
Step 7 Perform one of the following to specify the username and password that will be used for inner PEAP tunnel authentication:
•If you want your Windows username and password to also serve as your PEAP username and password, check the Use Windows User Name and Password check box.
•If you want to use a distinct username and password (which are registered with the RADIUS server) to start the PEAP authentication process, follow these steps:
a. Enter your PEAP username and password in the corresponding fields.
Note Your Windows username is filled in automatically. Simply delete your Windows username and enter your separate PEAP username.
b. Re-enter your password in the Confirm Password field.
Step 8 If you selected a certificate or entered a distinct username and password and you want to implement added security by further refining the network certificate that will be accepted and controlling the string used to set up the outer PEAP tunnel, follow these steps:
a. Click Advanced. The Configuration Settings window appears (see Figure 5-18).
Figure 5-18 Configuration Settings Window
b. Leave the Specific Server or Domain field blank to allow the client to accept a certificate from any server that supplies a certificate signed by the certificate authority listed in the Trusted Root Certification Authorities drop-down box on the Configure PEAP (EAP-MSCHAP V2) window (this is the recommended option) or enter the domain name of the server from which the client will accept a certificate.
c. If the Login Name field is not filled in automatically, enter your username with nothing after it (for example, jsmith).
Note Some RADIUS servers require that the same name be entered for both the inner and outer PEAP tunnels. That is, the same name may need to be entered in both the Login Name field and the User Name field on the Configure PEAP (EAP-MSCHAP V2) window. Contact your system administrator for information.
d. Click OK to save your settings.
Step 9 Click OK to save your settings and return to the Profile Management (Security) window.
Step 10 Perform one of the following to set the Allow Association to Mixed Cells parameter, which indicates whether the client adapter can associate to an access point that allows both WEP and non-WEP associations:
•Check the Allow Association to Mixed Cells check box if the access point to which the client adapter is to associate (or the VLAN to which the client will be assigned) has WEP set to Optional. Otherwise, the client is unable to establish a connection with the access point.
•Uncheck the Allow Association to Mixed Cells check box if the access point to which the client adapter is to associate (or the VLAN to which the client will be assigned) does not have WEP set to Optional. This is the default setting.
Note This parameter is available only if the 802.1x security option is selected.
Note For security reasons, Cisco recommends that WEP-enabled and WEP-disabled clients not be allowed in the same cell because broadcast packets are sent unencrypted, even to clients running WEP. However, you can enable VLANs on the access point to separate WEP-enabled and WEP-disabled clients.
Step 11 If you want to change the value of the Group Policy Delay parameter, enter a new value or use the up and down arrows to select a value between 0 and 65535 seconds. (Microsoft supports only values between 30 and 600 seconds. The default value is 60 seconds.)
The Group Policy Delay parameter specifies how much time elapses before the Windows logon process starts Group Policy, a Windows feature used by administrators to specify configuration options for groups of users. The objective is to delay the start of Group Policy until wireless network authentication occurs. The value that you set for this parameter goes into effect after the computer reboots with this profile set as the active profile.
Note A Microsoft hot fix is required in order to use this parameter on computers running Windows 2000. Refer to the "Installing a Microsoft Hot Fix for Group Policy Delay" section for information on obtaining and installing the hot fix.
Step 12 Click OK to save your settings and return to the Cisco Aironet Desktop Utility (Profile Management) window.
Step 13 Refer to Chapter 6, for instructions on authenticating using PEAP (EAP-MSCHAP V2).
Enabling PEAP (EAP-MSCHAP V2) Machine Authentication with Machine Credentials
The Host Based EAP option in the 802.1x EAP Type drop-down box on the Profile Management (Security) window enables client adapters that are configured through ADU to attempt to log into a domain using PEAP (EAP-MSCHAP V2) machine authentication with machine credentials. Doing so enables your computer to connect to the network prior to user logon. Follow these steps to enable this authentication type.
Note This procedure enables you to use PEAP (EAP-MSCHAP V2) machine authentication with machine credentials. If you want to enable PEAP (EAP-MSCHAP V2) machine authentication with user credentials, follow the instructions in the "Enabling PEAP (EAP-MSCHAP V2)" section.
Note Because this feature requires the Microsoft Wireless Configuration Manager to start and stop as you switch between host-based EAP and non-host-based EAP profiles, it works only for users with administrator or power-user privileges. An error message appears if you attempt to switch to or from a host-based EAP profile and you do not have the proper permissions.
Note To use this feature on a computer running Windows 2000, your computer must have the Microsoft 802.1X supplicant installed.
Note Host Based EAP is not included in the list of WPA/WPA2/CCKM EAP Type options on the Profile Management (Security) window in ADU because this feature is not supported for use with WPA or WPA2.
Step 1 Choose 802.1x under Set Security Options and Host Based EAP in the 802.1x EAP Type drop-down box.
Step 2 If you want to change the value of the Group Policy Delay parameter, enter a new value or use the up and down arrows to select a value between 0 and 65535 seconds. (Microsoft supports only values between 30 and 600 seconds. The default value is 60 seconds.)
The Group Policy Delay parameter specifies how much time elapses before the Windows logon process starts Group Policy, a Windows feature used by administrators to specify configuration options for groups of users. The objective is to delay the start of Group Policy until wireless network authentication occurs. The value that you set for this parameter goes into effect after the computer reboots with this profile set as the active profile.
Note A Microsoft hot fix is required in order to use this parameter on computers running Windows 2000. Refer to the "Installing a Microsoft Hot Fix for Group Policy Delay" section for information on obtaining and installing the hot fix.
Step 3 Click OK to save your settings.
Step 4 Activate this profile on the Cisco Aironet Desktop Utility (Profile Management) window. The Microsoft Wireless Configuration Manager starts.
Step 5 Click Start > Settings > Control Panel > Network and Dial-up Connections or Network Connections.
Step 6 Right-click your wireless connection.
Step 7 Click Properties. The Connection Properties window appears.
Step 8 Perform one of the following:
•On Windows 2000, click the Authentication tab.
•On Windows XP, choose the Wireless Networks tab, make sure that the Use Windows to configure my wireless network settings check box is checked, click the SSID of the access point to which you want the client adapter to associate from the list of available networks, click Configure, and choose the Authentication tab.
Step 9 For EAP type, choose Protected EAP (PEAP).
Step 10 Configure any applicable settings on the Protected EAP Properties window and subwindows.
Note Refer to the "Enabling PEAP (EAP-MSCHAP V2)" section if you need help configuring the PEAP (EAP-MSCHAP V2) settings.
Step 11 After you have finished the configuration, PEAP authentication should begin. Depending on the configuration settings you selected, you may be prompted for your PEAP username, password, and domain name. Note that you may need to minimize ADU in order to access the pop-up window that prompts you for your credentials.
Note You can have multiple host-based EAP profiles in ADU, but the Microsoft Wireless Configuration Manager maintains only one configuration. If you want to use different PEAP property settings for different host-based EAP profiles, you need to repeat the previous steps beginning with Step 4 every time you switch to a different host-based EAP profile.
Note When you activate a host-based EAP profile, the Microsoft Wireless Configuration Manager takes control of the client adapter's authentication attempt. However, when you activate a non-host-based EAP profile, ADU assumes this control.
Note If you experience problems while using a host-based EAP profile, make sure that 802.1X authentication is disabled for any other network connection.
Configuring Advanced Settings
To specify a server or domain name and a login name to use for authenticating user credentials (see Figure 5-19), follow these steps:
Figure 5-19 Configure Advanced Settings
Step 1 Leave the Specific Server or Domain field blank to allow the client to accept a certificate from any server that supplies a certificate signed by the selected certificate authority or enter the domain name of the server from which the client will accept a certificate.
Step 2 If the Login Name field is not filled in automatically, enter your username with nothing after it (for example, jsmith).
Step 3 Click OK to save your settings.
Disabling Static WEP, WPA/WPA2 Passphrase, or EAP
To disable static WEP, WPA/WPA2 passphrase, or EAP authentication [LEAP, EAP-FAST, EAP-TLS, PEAP (EAP-GTC), or PEAP (EAP-MSCHAP V2)] for a particular profile, choose None on the Profile Management (Security) window and click OK.
Note Choosing any security option other than Pre-Shared Key (Static WEP) on the Profile Management (Security) window disables static WEP automatically.
Note Choosing Pre-Shared Key (Static WEP) or WPA/WPA2 Passphrase on the Profile Management (Security) window disables EAP automatically.
Enabling Wi-Fi Multimedia
Wi-Fi Multimedia (WMM) is a component of the IEEE 802.11e wireless LAN standard for quality of service (QoS). It specifically supports priority tagging and queuing. QoS is an access point feature that enables networking professionals to provide preferential treatment to certain traffic at the expense of other traffic. Without QoS, the access point offers best-effort service to each packet, regardless of the packet contents or size. Implementing QoS in a wireless LAN makes network performance more predictable and bandwidth usage more effective.
Cisco recommends that you enable WMM if your computer is running a time-sensitive application for QoS-aware clients such as voice or video (for example, Cisco IP SoftPhone).
QoS and WMM must be enabled on the access point to which the client will associate. These features are supported on the access point in Cisco IOS Release 12.3(2)JA or later. Refer to the documentation for your access point for instructions on enabling these features.
WMM is supported automatically in the client adapter software. However, you must enable the Windows QoS Packet Scheduler to ensure WMM support. Follow the instructions below to enable the QoS Packet Scheduler on Windows 2000 or XP.
Note The QoS Packet Scheduler must be installed before you can enable it. It comes preinstalled on Windows XP; however, you must install it on Windows 2000.
Enabling the QoS Packet Scheduler on Windows 2000
Follow these steps to enable the QoS Packet Scheduler on a computer running Windows 2000.
Step 1 Double-click My Computer, Control Panel, and Network and Dial-up Connections.
Step 2 Right-click your wireless network connection.
Step 3 Click Properties. The Wireless Cisco Connection Properties window appears (see Figure 5-20).
Figure 5-20 Wireless Cisco Connection Properties Window
Step 4 If the QoS Packet Scheduler is already installed, it is included in the list of components that this connection uses. If it appears in the list, go to Step 8. Otherwise, go to the next step to install it.
Step 5 Click Install. The Select Network Component Type window appears (see Figure 5-21).
Figure 5-21 Select Network Component Type Window
Step 6 Choose Service and click Add. The Select Network Service window appears (see Figure 5-22).
Figure 5-22 Select Network Service Window
Step 7 Click QoS Packet Scheduler and OK. The Wireless Cisco Connection Properties window reappears, and the QoS Packet Scheduler is included in the list of connections.
Step 8 Check the QoS Packet Scheduler check box if it is not checked.
Step 9 Click OK.
Enabling the QoS Packet Scheduler on Windows XP
Follow these steps to enable the QoS Packet Scheduler on a computer running Windows XP.
Step 1 Click Control Panel.
Step 2 Double-click Network Connections.
Step 3 Right-click your wireless network connection.
Step 4 Click Properties. The Wireless Network Connection Properties window appears (see Figure 5-23).
Figure 5-23 Wireless Network Connection Properties Window
Step 5 Check the QoS Packet Scheduler check box, which appears in the list of items that this connection uses.
Step 6 Click OK.
Setting Roaming Parameters in the Windows Control Panel
The Cisco Aironet 802.11a/b/g Wireless Adapter Properties window (see Figure 5-24) in the Windows Control Panel enables you to set two parameters that regulate the client adapter's roaming capabilities.
Figure 5-24 Cisco Aironet 802.11a/b/g Wireless Adapter Properties Window
Follow these steps to access the roaming parameters.
Step 1 Double-click My Computer, Control Panel, and System.
Step 2 Click the Hardware tab and Device Manager.
Step 3 Double-click Network Adapters.
Step 4 Right-click Cisco Aironet 802.11a/b/g Wireless Adapter.
Step 5 Click Properties and the Advanced tab. The roaming parameters appear in the Property list. Table 5-5 lists and describes the client adapter's roaming parameters. Follow the instructions in the table to change the parameters.
Table 5-5 Roaming Parameters (in the Windows Control Panel)
|
|
BSS Aging Interval |
The amount of time (in seconds) that the client keeps an access point in its roaming scanlist after it can no longer communicate to that device. The higher the value, the greater the number of access points to which the client may roam.
Range: 20 to 300 seconds (in 10-second increments)
Note Cisco recommends that you set the BSS Aging Interval to twice the value of the Scan Valid Interval. For example, if the Scan Valid Interval is 50, the BSS Aging Interval would be 100. |
Scan Valid Interval |
The amount of time (in seconds) before the client starts scanning for a better access point after reaching the roaming threshold or missing beacons. (See the threshold criteria in the table below.) The higher the value, the less time the client spends scanning for a better access point and the more time it has to send data.
Range: 20 to 120 seconds (in 5-second increments)
Note The client does not scan for a new access point as long as it has a good connection and is passing data. |
|
Signal Strength Threshold (dBm)
|
Transmit Rate
Threshold (Mbps)
|
5 GHz, 54 Mbps or 2.4 GHz, 54 Mbps |
24 |
24 |
2.4 GHz, 11 Mbps (other modes enabled) |
24 |
9 |
2.4 GHz, 11 Mbps (only mode enabled) |
24 |
5 |
The default configuration of the client adapter software is optimized for high throughput and the lowest power consumption. However, in some environments, this configuration can cause the client adapter to unnecessarily stay with the currently associated access point longer than necessary.
If your application requires a faster roaming response, configure the BSS Aging Interval and Scan Valid Interval parameters as follows:
•Set the BSS Aging Interval parameter to 20
•Set the Scan Valid Interval parameter to 20
Note If you are using client software prior to 2.7.0.2, you will not be able to set the BSS Aging Interval parameter to 20. In that case, set it to 30.
Configuring Band Usage
If your AP coverage permits it, follow these steps to configure the client profile only in ADU to use the 5GHz (802.11a) or 2.4GHz (802.11b/g) band, not both:
Step 1 Launch ADU.
Step 2 Click Profile Management.
Step 3 Select the profile of interest and click Modify.
Step 4 Click Advanced.
Step 5 Under Wireless Mode, uncheck the rates that you do not intend to use.
If you do not use ADU to manage CB21AG, then you must use registry settings to select the rates. Follow these steps:
1. Launch regedit and navigate to the following entry:
HKLM\System\CurrentControlSet\Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}
2. Right-click and choose Find and find the variable called "NetBand."
This variable will be under a four-digit subkey whose DriverDesc value is "Cisco Aironet 802.11a/b/g Wireless Adapter."
The NetBand REG_SZ variable is a bitmask of supported rates. By default, this variable it is set to 15 decimal (0x0F). The supported values are:
–802.11a 0x01
–(not used) 0x02
–802.11b 0x04
–802.11g 0x08
–(not used) 0x10
For example, to support only 11b and 11g rates, the bitmask would be 0x04 + 0x08 = 0x0C = 12 decimal.