Overview; Overview Of Security Features; Static Wep Keys - Cisco AIR-PCM352 - Aironet 350 Series 11Mbps Wireless LAN PC Card Adapter Installation And Configuration Manual

Overview

Overview
This appendix provides instructions for configuring the client adapter through Windows CE .NET
(instead of through ACU). The
options that are available for use with this operating system so that you can make an informed decision
before you begin the configuration process. In addition, the appendix also provides basic information on
using Windows CE .NET to specify the networks to which the client adapter associates.
The instructions in this appendix are specific to PPC 2003 devices. The same configuration parameters
Note
must be set on other Windows CE .NET devices; however, the procedure used to set those parameters
may differ. If you require more information on configuring or using your client adapter with Windows
CE .NET, refer to the documentation that came with your device and Microsoft's documentation for
Windows CE .NET.

Overview of Security Features

When you use your client adapter with Windows CE .NET, 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
WEP Keys"
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.

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.
Static WEP keys are write-only and temporary; however, you do not need to re-enter them each time the
client adapter is inserted or the Windows CE .NET device is reset. This is because the keys are stored
(in an encrypted format for security reasons) in the registry of the 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.
Cisco Aironet 350 Series Wireless LAN Client Adapters Installation and Configuration Guide for Windows CE
E-2
"Overview of Security Features"
and "Dynamic WEP Keys with EAP"
Appendix E Configuring the Client Adapter through Windows CE .NET
section below describes the security
sections below can help you to decide which type of
"Static
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