Wireless Laptop Network Support

Windows XP, Lindows OS, and Macintosh OS X all have integrated support
for 802.11 wireless NIC drivers. Almost all the major NIC vendors
support 802.11b (and more are offering support for 802.11a integrated into the same wireless products). Since this book illustrates the vulnerabilities
in WEP, we now look at how a laptop running Windows XP exemplifies
using WEP authentication procedures in a typical wireless environment.

Windows XP supports the following types of features and functionality:


Automatic network detection and association—Wireless NIC
cards employ a logical algorithm to detect any available wireless network
and associate with the best one in range.


Media sense—This feature is used to determine when a WLAN NIC
has roamed from one access point to another. As a result, it may
require that you reauthenticate yourself and employ other types of
configuration changes that must be set properly so that you don’t
compromise the security of your wireless network.


Network location support—This functionality allows Windows
applications to be notified as soon as the computer roams through the
wireless network. Programs also have the power to update their settings
automatically with respect to the changing parameters of the
current network settings.


Power mode support—Wireless NICs are automatically told when
the power coming from the laptop device is from an AC adapter or the
battery. This information makes it possible to conserve energy when
necessary and shut down the system (or put it to sleep) to save power
and extend the operating life of the laptop computer when it is in use
for mobile applications.