Cisco Systems CB21AG manual Static WEP Keys, EAP with Dynamic WEP Keys

Chapter 5 Configuring the Client Adapter

Setting Security Parameters

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 on page 5-24for 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 credentials (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.

Cisco Aironet 802.11a/b/g Wireless LAN Client Adapters (CB21AG and PI21AG) Installation and Configuration Guide

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