Network Everywhere NWP11B, Руководство пользователя

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What is Roaming?
Roaming is the ability of a portable computer user to communicate continu-
ously while moving freely throughout an area greater than that covered by a sin-
gle Wireless Network Access Point.
To achieve true seamless connectivity, the wireless LAN must incorporate a
number of different functions. Each node and Wireless Network Access Point,
for example, must always acknowledge receipt of each message. Each node
must maintain contact with the wireless network even when not actually trans-
mitting data. Achieving these functions simultaneously requires a dynamic RF
networking technology that links Wireless Network 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 qual-
ity, as well as the message load currently being carried by each Wireless
Network Access Point and the distance of each Wireless Network Access Point
to the wired backbone. Based on that information, the node next selects the
right Wireless Network 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 sys-
tem to determine whether it is in touch with the original Wireless Network
Access Point or whether it should seek a new one. When a node no longer
receives acknowledgment from its original Wireless Network Access Point, it
undertakes a new search. Upon finding a new Wireless Network Access Point,
it then re-registers, and the communication process continues.
What is BSS ID?
A specific Ad-hoc LAN is called a Basic Service Set (BSS). Computers in a
BSS must be configured with the same BSS ID.
What is ESSID?
An Infrastructure configuration could also support roaming capability for
mobile workers. More than one BSS can be configured as an Extended Service
Set (ESS). Users within an ESS could roam freely between BSSs while main-
taining a continuous connection to the wireless network stations and Wireless
Network Access Points.
What is ISM band?
The FCC and their counterparts outside of the U.S. have set aside bandwidth
for unlicensed use in the ISM (Industrial, Scientific and Medical) band.
Spectrum in the vicinity of 2.4 GHz, in particular, is being made available
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3. I cannot communicate with the other computers linked via the Ethernet
in the Infrastructure configuration.
• Make sure that the notebook PC to which the Wireless Notebook Adapter is
associated is powered on.
• Make sure that your Wireless Notebook Adapter is configured on the same
channel and with the same security options as the other computers in the
Infrastructure configuration.
Can I run an application from a remote computer over the wireless net-
work?
This will depend on whether or not the application is designed to be used over a
network. Consult the application’s documentation to determine if it supports
operation over a network.
Can I play multiplayer games with other users of the wireless network?
Yes, as long as the game supports multiple players over a LAN (local area net-
work). Refer to the game’s documentation for more information.
What is the IEEE 802.11b standard?
The IEEE 802.11b Wireless LAN standards subcommittee formulates standards
for the industry. The objective is to enable wireless LAN hardware from different
manufacturers to communicate.
What IEEE 802.11 features are supported?
The product supports the following IEEE 802.11 functions:
•
CSMA/CA plus Acknowledge protocol
• Multi-Channel Roaming
• Automatic Rate Selection
• RTS/CTS feature
• Fragmentation
• Power Management
What is Ad-hoc?
An Ad-hoc wireless LAN is a group of computers, each with a Wireless
Notebook Adapter, connected as an independent wireless LAN. An Ad-hoc wire-
less LAN is applicable at a departmental scale for a branch or SOHO operation.
What is Infrastructure?
An integrated wireless and wired LAN is called an Infrastructure configuration.
Infrastructure is applicable to enterprise scale for wireless access to a central
database, or wireless application for mobile workers.
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Wireless Notebook Adapter Network Everywhere ™ Series
Frequently Asked Questions