ZyXEL Communications P-660HN-TxA, Руководство пользователя

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Chapter 8 Wireless LAN
P-660HN-TxA User’s Guide
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For example, if the wireless network has a RADIUS server, you can choose WPA
or WPA2. If users do not log in to the wireless network, you can choose no
encryption, Static WEP, WPA-PSK, or WPA2-PSK.
Usually, you should set up the strongest encryption that every device in the
wireless network supports. For example, suppose you have a wireless network
with the ZyXEL Device and you do not have a RADIUS server. Therefore, there is
no authentication. Suppose the wireless network has two devices. Device A only
supports WEP, and device B supports WEP and WPA. Therefore, you should set up
Static WEP in the wireless network.
Note: It is recommended that wireless networks use WPA-PSK , WPA , or stronger
encryption. The other types of encryption are better than none at all, but it is still
possible for unauthorized wireless devices to figure out the original information
pretty quickly.
When you select WPA2 or WPA2-PSK in your ZyXEL Device, you can also select
an option (WPA compatible) to support WPA as well. In this case, if some of the
devices support WPA and some support WPA2, you should set up WPA2-PSK or
WPA2 (depending on the type of wireless network login) and select the WPA
compatible option in the ZyXEL Device.
Many types of encryption use a key to protect the information in the wireless
network. The longer the key, the stronger the encryption. Every device in the
wireless network must have the same key.
8.8.4 Signal Problems
Because wireless networks are radio networks, their signals are subject to
limitations of distance, interference and absorption.
Problems with distance occur when the two radios are too far apart. Problems with
interference occur when other radio waves interrupt the data signal. Interference
may come from other radio transmissions, such as military or air traffic control
communications, or from machines that are coincidental emitters such as electric
motors or microwaves. Problems with absorption occur when physical objects
(such as thick walls) are between the two radios, muffling the signal.
8.8.5 BSS
A Basic Service Set (BSS) exists when all communications between wireless
stations or between a wireless station and a wired network client go through one
access point (AP).
Intra-BSS traffic is traffic between wireless stations in the BSS. When Intra-BSS
traffic blocking is disabled, wireless station A and B can access the wired network