Novell LINUX ENTERPRISE SERVER 10 - INSTALLATION AND ADMINISTRATION 11-05-2007, Руководство по установке

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system tries to use the highest possible data transmission rate. Some WLAN cards
do not support the setting of bit rates.
Access Point
In an environment with several access points, one of them can be preselected by
specifying the MAC address.
29.1.4 Utilities
hostap (package
hostap
) is used to run a WLAN card as an access point. More infor-
mation about this package is available at the project home page (
http://hostap
.epitest.fi/
).
kismet (package
kismet
) is a network diagnosis tool with which to listen to the WLAN
packet traffic. In this way, you can also detect any intrusion attempts in your network.
More information is available at
http://www.kismetwireless.net/
and in
the manual page.
29.1.5 Tips and Tricks for Setting Up a
WLAN
These tips can help tweak speed and stability as well as security aspects of your WLAN.
Stability and Speed
The performance and reliability of a wireless network mainly depend on whether the
participating stations receive a clean signal from the other stations. Obstructions like
walls greatly weaken the signal. The more the signal strength sinks, the more the
transmission slows down. During operation, check the signal strength with the iwconfig
utility on the command line (
Link Quality
field) or with NetworkManager or
KNetworkManager. If you have problems with the signal quality, try to set up the devices
somewhere else or adjust the position of the antennas of your access points. Auxiliary
antennas that substantially improve the reception are available for a number of PCMCIA
WLAN cards. The rate specified by the manufacturer, such as 54 Mbit/s, is a nominal
value that represents the theoretical maximum. In practice, the maximum data
throughput is no more than half this value.
Wireless Communication 537