User's Manual

Wistron
NeWeb
Wistron NeWeb Corporation
20 Park Avenue II, Hsinchu Science Park, Hsinchu 308, Taiwan, R.O.C.
Phone: 886-3-666-7799 Fax: 886-3-666-7711
Website: www.wneweb.com
Wistron NeWeb Confidential Document
31
5. Would the information be intercepted while transmitting on air?
WLAN features two-fold protection in security. On the hardware side, as with Direct Sequence
Spread Spectrum technology, it has the inherent security feature of scrambling. On the
software side, WLAN offers the encryption function (WEP) to enhance security and access
control.
6. What is WEP?
WEP is Wired Equivalent Privacy, a data privacy mechanism based on a 64-bit or 128-bit
shared key algorithm, as described in the IEEE 802.11 standard.
7. What is infrastructure mode?
When a wireless network is set to infrastructure mode, the wireless network is configured to
communicate with a wired network through a wireless access point.
8. What is roaming?
Roaming is the ability of a portable computer user to communicate continuously while moving
freely throughout an area greater than that covered by a single access point. Before using the
roaming function, the workstation must make sure that it is the same channel number with the
access point of dedicated coverage area.
To achieve true seamless connectivity, the wireless LAN must incorporate a number of
different functions. Each node and access point, for example, must always acknowledge
receipt of each message. Each node must maintain contact with the wireless network even
when not actually transmitting data. Achieving these functions simultaneously requires a
dynamic RF networking technology that links access points and nodes. In such a system, the
user’s end node undertakes a search for the best possible access to the system. First, it
evaluates such factors as signal strength and quality, as well as the message load currently
being carried by each access point and the distance of each access point to the wired
backbone. Based on that information, the node next selects the right access point and
registers its address. Communications between end node and host computer can then be
transmitted up and down the backbone. As the user moves on, the end node’s RF transmitter
regularly checks the system to determine whether it is in touch with the original access point
or whether it should seek a new one. When a node no longer receives acknowledgment from
its original access point, it undertakes a new search. Upon finding a new access point, it then
re-registers, and the communication process continues.