Inventec Multimedia and Telecom EW-7317UG-2E 802.11g Wireless LAN Mini USB Adapter User Manual Manual
Inventec Multimedia & Telecom Corporation 802.11g Wireless LAN Mini USB Adapter Manual
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User Manual
Version: 1.0
(Nov., 2005)
COPYRIGHT
Copyright © 2005/2006 by this company. All rights reserved. No part of this
publication may be reproduced, transmitted, transcribed, stored in a retrieval system,
or translated into any language or computer language, in any form or by any means,
electronic, mechanical, magnetic, optical, chemical, manual or otherwise, without the
prior written permission of this company
This company makes no representations or warranties, either expressed or implied,
with respect to the contents hereof and specifically disclaims any warranties,
merchantability or fitness for any particular purpose. Any software described in this
manual is sold or licensed "as is". Should the programs prove defective following
their purchase, the buyer (and not this company, its distributor, or its dealer) assumes
the entire cost of all necessary servicing, repair, and any incidental or consequential
damages resulting from any defect in the software. Further, this company reserves
the right to revise this publication and to make changes from time to time in the
contents hereof without obligation to notify any person of such revision or changes.
All brand and product names mentioned in this manual are trademarks and/or registered trademarks
of their respective holders.
Federal Communication Commission
Interference Statement
This equipment has been tested and found to comply with the limits for a Class B
digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to
provide reasonable protection against harmful interference in a residential
installation. This equipment generates, uses and can radiate radio frequency energy
and, if not installed and used in accordance with the instructions, may cause harmful
interference to radio communications. However, there is no guarantee that
interference will not occur in a particular installation. If this equipment does cause
harmful interference to radio or television reception, which can be determined by
turning the equipment off and on, the user is encouraged to try to correct the
interference by one of the following measures:
-Reorient or relocate the receiving antenna.
-Increase the separation between the equipment and receiver.
-Connect the equipment into an outlet on a circuit different from that to which the
receiver is connected.
-Consult the dealer or an experienced radio/TV technician for help.
This device complies with Part 15 of the FCC Rules. Operation is subject to the
following two conditions: (1) This device may not cause harmful interference, and (2)
this device must accept any interference received, including interference that may
cause undesired operation.
FCC Caution: Any changes or modifications not expressly approved by the party
responsible for compliance could void the user's authority to operate this equipment.
IMPORTANT NOTE:
FCC Radiation Exposure Statement:
This equipment complies with FCC radiation exposure limits set forth for an
uncontrolled environment. This equipment should be installed and operated with
minimum distance 20cm between the radiator & your body.
This transmitter must not be co-located or operating in conjunction with any other
antenna or transmitter.
This device is intended only for OEM integrators under the following conditions:
1) The antenna must be installed such that 20 cm is maintained between the antenna
and users, and
2) The transmitter adapter may not be co-located with any other transmitter or
antenna.
As long as 2 conditions above are met, further transmitter test will not be required.
However, the OEM integrator is still responsible for testing their end-product for any
additional compliance requirements required with this adapter installed (for example,
digital device emissions, PC peripheral requirements, etc.).
IMPORTANT NOTE:
In the event that these conditions can not be met (for example certain laptop
configurations or co-location with another transmitter), then the FCC authorization is
no longer considered valid and the FCC ID can not be used on the final product. In
these circumstances, the OEM integrator will be responsible for re-evaluating the end
product (including the transmitter) and obtaining a separate FCC authorization.
End Product Labeling
This transmitter adapter is authorized only for use in device where the antenna may
be installed such that 20 cm may be maintained between the antenna and users (for
example: Internet Radio and Desktop PC). The final end product must be labeled in a
visible area with the following: “Contains TX FCC ID: SVKEW-7317UG-2E”.
Manual Information That Must be Included
The OEM integrator has to be aware not to provide information to the end user
regarding how to install or remove this RF adapter in the user manual of the end
product which integrates this adapter.
The users manual for OEM integrators must include the following information in a
prominent location “IMPORTANT NOTE: To comply with FCC RF exposure
compliance requirements, the antenna used for this transmitter must be installed to
provide a separation distance of at least 20 cm from all persons and must not be co-
located or operating in conjunction with any other antenna or transmitter.
R&TTE Compliance Statement
This equipment complies with all the requirements of DIRECTIVE 1999/5/CE OF
THE EUROPEAN PARLIAMENT AND THE COUNCIL of March 9, 1999 on radio
equipment and telecommunication terminal Equipment and the mutual recognition of
their conformity (R&TTE)
The R&TTE Directive repeals and replaces in the directive 98/13/EEC
(Telecommunications Terminal Equipment and Satellite Earth Station Equipment) As
of April 8, 2000.
Safety
This equipment is designed with the utmost care for the safety of those who install
and use it. However, special attention must be paid to the dangers of electric shock
and static electricity when working with electrical equipment. All guidelines of this
and of the computer manufacture must therefore be allowed at all times to ensure the
safe use of the equipment.
EU Countries Intended for Use
The ETSI version of this device is intended for home and office use in Austria,
Belgium, Denmark, Finland, France, Germany, Greece, Ireland, Italy, Luxembourg,
the Netherlands, Portugal, Spain, Sweden, and the United Kingdom.
The ETSI version of this device is also authorized for use in EFTA member states:
Iceland, Liechtenstein, Norway, and Switzerland.
EU Countries Not intended for use
None.
CONTENTS
1 INTRODUCTION.............................................................................1
1.1 FEATURES .................................................................................................... 1
1.2 SPECIFICATIONS............................................................................................ 1
2 INSTALLATION PROCEDURE .....................................................3
3 CONFIGURATION UTILITY .........................................................8
3.1 WIRELESS CONNECTION STATUS.................................................................... 8
3.2 GENERAL CONNECTION SETTING ................................................................. 10
3.3 WEP AND WPA ENCRYPTION ...................................................................... 12
3.3.1 WEP Setting........................................................................................................... 13
3.3.2 WPA Setting .......................................................................................................... 14
3.4 SOFTWARE AP MODE.................................................................................. 16
3.4.1 AP Connection Status ............................................................................................. 16
3.4.2 AP General Connection Setting............................................................................... 17
3.4.3 MAC Address Filter ............................................................................................... 20
4 TROUBLESHOOTING ..................................................................22
1
1 Introduction
Thank you for purchasing the 802.11g Wireless LAN Mini USB Adapter. This USB Adapter is
designed to comply with IEEE 802.11g Wireless LAN standard.
This adapter supports 64/128/256-bit WEP data encryption that protects your wireless network from
eavesdropping. It also supports WPA (Wi-Fi Protected Access) feature that combines IEEE 802.1x
and TKIP (Temporal Key Integrity Protocol) technologies. Client users are required to authorize
before accessing to APs or AP Routers, and the data transmitted in the network is
encrypted/decrypted by a dynamically changed secret key. This adapter has built-in AES engine
which ensure the highest degree of security and authenticity for digital information and it is the
most advanced solution defined by IEEE 802.11i for the security in the wireless network.
This adapter is cost-effective, together with the versatile features; it is the best solution for you to
build your wireless network.
1.1 Features
• Complies with the IEEE 802.11b and IEEE 802.11g 2.4GHz standards.
• Up to 54Mbps high data transfer rate.
• Support 64/128/256-bit WEP, WPA (TKIP, IEEE 802.1x) and AES functions for high level of
security.
• Supports Software AP function, which turns the wireless station into a wireless AP.
• Complies with IEEE 802.11d country roaming standard.
• Support the most popular operating system: Windows 98SE/Me/2000/XP.
• Supports USB 2.0/1.1/1.0 interface.
• Mini-size design.
1.2 Specifications
• Standard: IEEE 802.11g/b
• Bus Type: USB 2.0 Type A
• Frequency Band: 2.4000~2.4835GHz (Industrial Scientific Medical Band)
• Modulation: OFDM with BPSK, QPSK, 16QAM, 64QAM (11g)
BPSK, QPSK, CCK (11b)
• Data Rate: 54/48/36/24/18/12/11/9/6/5.5/2/1Mbps auto fallback
• Security: 64/128/256-bit WEP Data Encryption, WPA (IEEE 802.1x with TKIP) and AES
• Antenna: 2.4GHz printed antenna
• Drivers: Windows 98SE/Me/2000/XP/2003 Server
• LED: Link/Activity
• Transmit Power: 11g: 15dBm (Typical), 11b: 18dBm (Typical)
• Dimension: 9(H) x 27(W) x 87(D)
• Temperature: 32~131°F (0 ~55°C)
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• Humidity: 0-95% (NonCondensing)
• Certification: FCC, CE
3
2 Installation Procedure
Before you proceed with the installation, please notice following descriptions.
Note1: Please do not install the USB adapter into your computer before installing the software program from
the CD.
Note2: The following installation was operated in Windows XP. (Procedures are similar for Windows
98SE/Me/2000/2003 Server.)
Note3: If you have installed the Wireless PC Card driver & utility before, please uninstall the old version first.
Please follow below instructions to install the USB Adapter.
I. Install the Configuration Utility
A. Insert the Installation CD to your CD-ROM Drive. Execute the “setup” program.
B. If you want to install the software program in another location, click “Browser” and select an
alternative destination. Then, click “Next”.
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C. Click “Continue Anyway” to finish the installation.
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II. Install the USB Adapter
A. Plug the USB Adapter into the USB port of your computer.
B. The “Found New Hardware Wizard” is displayed, select “Install the software automatically
(Recommended)” and click “Next”.
C. Click “Continue Anyway” and the system will start to install the USB adapter.
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D. Click “Finish” to complete the installation.
III. Using the Configuration Utility
To setup the USB adapter, double-click the icon in the system tray.
For Windows XP, there is a “Windows Zero Configuration Tool” by default for you to setup
wireless clients. If you want to use the Utility of the USB adapter, please follow one of the ways as
below.
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First Way
A. Double-click the utility
icon in the system tray.
B. Click “Yes” to use the
utility of the USB adapter.
Second Way
A. Double-click the icon.
B. Click “Advance”.
C. Uncheck “Use Windows to
configure my wireless
network settings”.
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3 Configuration Utility
The Configuration Utility is a powerful application that helps you configure the 802.11g Wireless
LAN Mini USB Adapter and monitor the link status during the communication process.
The Configuration Utility appears as an icon on the system tray of Windows while the card is
running. You can open it by double-click on the icon.
Right click the icon, there are some items for you to operate the configuration utility.
z Open Utility Window
Select “Open Utility Window” to open the Configuration Utility tool.
z Exit ZDWlan
Select “Exit ZDWlan” to close the Configuration Utility tool.
Before using the utility, you have to know some restrictions of the utility.
1. If you want to connect to 11g (up to 54Mbps) network, please ensure to install the adapter to
PC or laptop with USB 2.0 interface. This adapter runs at lower performance while you connect
it to the USB 1.1/1.0 port of your computer instead.
2. This adapter will work in 11b mode when the network type is in Ad Hoc mode. It is defines by
Wi-Fi organization. If you want to enable the data rate up to 54Mbps (11g), please follow steps
listed below.
A. Go to “Network Connections”.
B. Right Click the “Wireless Network Connection” and select “Properties”.
C. From the pop-up screen, click “Configure”.
D. Enter into “Advanced” page of the “Properties” screen.
E. Enable the setting of “IBSS_G_Mode”.
3.1 Wireless Connection Status
When you open the Configuration Utility, the system will scan all the channels to find all the access
points/stations within the accessible range of your card and automatically connect to the wireless
device with the highest signal strength. From the screen, you may know all the infomration about
the wireless connection.
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Parameter Description
Mode Station – Set the USB adapter a wireless client.
Access Point – Turns the USB adapter to function as a wireless AP.
Please refer to Section 3.5 for the AP settings.
Network Adapter Display the product information of the USB Adapter.
Available Network Display all the SSID and Signal Strength of wireless stations nearby. To
re-survey the available wireless devices please click “Refresh”.
There are two ways to automatically make the connection between the
USB Adapter and the wireless station on the list.
1. Double-click the wireless station on the list directly.
2. Select the station you intend to connect and then click “Connect
this site“.
Current Network Information Display the information about the wireless network this adapter is
connecting to. The information includes Channel, Type, SSID, TX Rate
and Encrypt settings. Note: Please refer to Section 3.2 for the
description of each item.
More Setting For setting more functions including disable/enable WEP and Power
Saving Mode, etc. Please refer to Section 3.2, 3.3 and 3.4.
Link Status Display the status of the wireless connection.
BSSID Display the MAC Address of the network the adapter is connecting to.
Parameter Description
Signal Strength This bar shows the signal strength level. The higher percentage shown
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in the bar, the more radio signal been received by the adapter. This
indicator helps to find the proper position of the wireless station for
quality network operation.
Link Quality This bar indicates the quality of the link. The higher the percentage, the
better the quality.
TX Frame It shows the number of data frames which are transmitted by the adapter
successfully.
RX Frame It shows the number of data frames which are received by the adapter
successfully.
3.2 General Connection Setting
Click “More Setting”, users are allowed to setup the wireless connection setting, Encryption Setting
of the USB adapter and other advanced functions.
Parameter Description
General Connection Setting
Channel Select the number of the radio channel used for the networking. The
channel setting of the wireless stations within a network should be the
same.
Parameter Description
Tx Rate There are several options including
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Auto/1/2/5.5/11/6/9/12/18/24/36/48/54Mbps for you to select. When the
“Auto” is selected, the device will choose the most suitable
transmission rate automatically. The higher data rate you designated in
the network, the shorter distance is allowed between the adapter and the
wireless stations.
When the adapter works in 11b mode, the maximum data rate is 11Mbps
so that there are only “Auto/1/2/5.5/11Mbps” options you can select.
SSID The SSID (up to 32 printable ASCII characters) is the unique name
identified in a WLAN. The ID prevents the unintentional merging of
two co-located WLANs.
You may specify a SSID for the adapter and then only the device with
the same SSID can interconnect to the adapter.
Any If “Any“ check box is enabled, the adapter will survey and connect to
one of the available wireless stations without checking the consistency
of channel and SSID with the wireless station.
Network Type Ad-Hoc – This mode enables wireless network adapters interconnecting
without through AP or Router. Select this mode if there is no AP or
Router in the network.
Infrastructure – This operation mode requires the presence of an
802.11 Access Point. All communication is done via the Access Point or
Router.
Change/Apply Clcik “Change“ will enable you to setup the parameters of “General
Connection Setting“. In the meantime, the button will change to
“Apply“ for you to confirm your settings.
Encryption Setting In the block, users may enable/disable WEP and WPA encryption within
the network. Please refer to Section 3.3 for more description.
Parameter Description
Authentication Mode This setting has to be consistent with the wireless networks that the
adapter intends to connect.
Open System – No authentication is needed among the wireless
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network.
Shared Key – Only wireless stations using a shared key (WEP Key
identified) are allowed to connecting each other.
Auto – Auto switch the authentication algorithm depending on the
wireless networks that the adapter is connecting to.
WEP Encryption Key Setting Click this button to setup the WEP key. Please refer to Section 3.3 for
the details.
WPA Encryption Setting Click this button to setup the WPA function. Please refer to Section 3.3
for the details.
Profile
Profile Name You can save the network setting as a profile. To connect to the
network without making additional configuration, you can load the
profile.
Load Load the setting values from the file in the “Profile Name“ list. The
new settings will be activated immediately.
Save Current Input a file name and click “Save Current“ to write the current setting
values to be a profile in the “Profile Name“ list.
Delete Delete the profile you select.
Other
Advanced Setting... For more advanced setting, please click it. To know more of the setting,
please refer to Section 3.4.
Information To view the version of the driver, firmware and the MAC Address of
the adapter, click the button.
3.3 WEP and WPA Encryption
WEP is an data encryption algorithm, which protects Wireless LAN data in the network against
eavesdropping. WEP has been found that it has some security problems. The adapter supports WPA
(Wi-Fi Protected Access) that combines IEEE 802.1x and TKIP (Temporal Key Integrity Protocol)
13
technologies. Client users are required to authorize before accessing to Aps or AP Routers, and the
data transmitted in the network is encrypted/decrypted by a dynamically changed secret key. This
adapter is also built-in AES engine which ensure the highest degree of security and authenticity for
digital information and it is the most advanced solution defined by IEEE 802.11i for the security in
the wireless network.
3.3.1 WEP Setting
Parameter Description
Key Length You may select the 64-bit, 128-bit or 256-bit to encrypt transmitted
data. Larger key length will provide higher level of security, but the
throughput will be lower.
Default Key ID Select one of the keys (1~4) as the encryption key.
Key Format Hexdecimal – Only “A-F“, “a-f“ and “0-9“ are allowed to be set as
WEP key.
ASCII –Numerical values, characters or signs are allowed to be the
WEP key. It is more recognizable for user.
Parameter Description
Key1 ~ Key4 The keys are used to encrypt data transmitted in the wireless network.
Fill the text box by following the rules below.
64-bit – Input 10-digit Hex values or 5-digit ASCII values as the
encryption keys. For example: “0123456aef“ or “Guest“.
128-bit – Input 26-digit Hex values or 13-digit ASCII values as the
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encryption keys. For example: “01234567890123456789abcdef“ or
“administrator“.
256-bit – Input 58-digit Hex values or 29-digit ASCII values as the
encryption keys.
Change/Apply Clcik “Change“ will enable you to setup the WEP key. In the meantime,
the button will change to “Apply“ for you to confirm your settings.
3.3.2 WPA Setting
The adapter can automatically detect the WPA setting of the AP which the adapter intends to
connect to. To connect to the AP, you should setup the same setting with the AP.
There are two kinds of WPA mode: WPA and WPA-PSK. WPA is designed for enterprise which
requires a RADIUS Server and Certificate Server for the authentication. WPA-PSK is a special
mode designed for home and small business users who do not have access to network authentication
servers. In this mode, the user manually enters the starting password in their access point or gateway,
as well as in each wireless stations in the network. WPA takes over automatically from that point,
keeping unauthorized users that don't have the matching password from joining the network, while
encrypting the data traveling between authorized devices.
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Parameter Description
Connect Information It is the setting for WPA mode.
Protocol This adapter supports two kind of protocol for authentication including
TLS and PEAP. TLS and PEAP requires a certificate which is provided
by the Certificate Server. PEAP requires a set of user name and
password in addition. To get the certificate and the personal user name
and password, please contact with your administrator.
TLS – Select a certificate from the “Certificate“ list.
PEAP – Input the “User Name“ and “Password“ and also select a
certificate from the “Certificate“ list.
User Name It is the setting for PEAP protocol.
Password It is the setting for PEAP protocol.
Pre-shared Key It is the setting for WPA-PSK mode. Input a 8 to 63 digits of ASCII
format to be the password for the authentication within the network.
Certificate All the available certificates for TLS or PEAP will display in the list.
Please select a proper certificate for the wireless authentication.
Parameter Description
WEP Key If the AP uses WEP data encryption function, please clcik “WEP KEY
SETTING“ to setup the WEP key.
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WEP KEY SETTING Setup the four sets of WEP key by clicking the button.
Change/Apply Clcik “Change“ will enable you to setup the WPA setting. In the
meantime, the button will change to “Apply“ for you to confirm your
settings.
3.4 Software AP Mode
This adapter can run as a wireless AP. The relative configurations of the AP including channel,
SSID, MAC Address Filtering, WEP encryption and so on are described as follows.
3.4.1 AP Connection Status
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Parameter Description
Mode Station – Set the USB adapter a wireless client.
Access Point – Turns the USB adapter to function as a wireless AP.
Network Adapter Display the product information of the USB Adapter.
Connect Station List Display all the MAC Addresses of the wireless adapters which are
connecting to the AP.
Current Network Setting Display the connection setting of the current network. It includes
Channel, SSID, WEP and TX Power Level.
More Setting For setting more functions including disable/enable WEP, MAC
Address Filter and Bridge Adapter, etc. Please refer to Section 3.5.2.
TX Frame It shows the number of data frames which are transmitted by the AP
successfully.
RX Frame It shows the number of data frames which are received by the AP
successfully.
3.4.2 AP General Connection Setting
Click “More Setting”, users are allowed to setup the AP connection setting, Encryption Setting and
other advanced functions.
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Parameter Description
General Connection Setting
Channel Select the number of the radio channel used by the AP. The wireless
adapters which connects to the AP should set up the same channel.
Basic Rate Select the basic data transmission speed supports by the AP. When the
AP works in 11b mode, the maximum data rate is 11Mbps so that there
are two options including “1, 2 Mbps“ and “1, 2, 5.5, 11Mbps” you can
select.
Parameter Description
Tx Rate There are several options including
Auto/1/2/5.5/11/6/9/12/18/24/36/48/54Mbps for you to select. When the
“Auto” is selected, the device will choose the most suitable
transmission rate automatically. The higher data rate you designated in
19
the network, the shorter distance is allowed between the adapter and the
wireless stations.
When the adapter works in 11b mode, the maximum data rate is 11Mbps
so that there are only “Auto/1/2/5.5/11Mbps” options you can select.
SSID The SSID (up to 32 printable ASCII characters) is the unique name
identified in a WLAN. The ID prevents the unintentional merging of
two co-located WLANs.
The default SSID of the AP is WLAN_AP. Wireless adapters connect to
the AP should set up the same SSID as the AP.
Hide SSID If “Hide SSID“ check box is enabled, the AP will not appear in the site
survey list of any wireless adapters. It means Only the wireless adapters
set the same SSID can connect to the AP. It aviods the AP being
connected by unauthorized users.
Tx Power There are four levels for you to setup the transmission power of the AP.
The higher transmission power, the larger transmission distance and
wireless coverage.
Change/Apply Clcik “Change“ will enable you to setup the parameters of “General
Connection Setting“. In the meantime, the button will change to
“Apply“ for you to confirm your settings.
WEP Enable or disable WEP encryption function. If the WEP function is
enabled, only wireless adapters with the same default key and WEP key
setting can connect to the AP.
Setting Click “Setting“ to setup the WEP key. Please refer to Section 3.3 for
more description.
Authentication Mode Open System – No authentication is needed for connecting to the AP.
Shared Key – Only wireless adapters using a shared key (WEP Key identified)
are allowed to connecting to the AP.
Parameter Description
Fragement The value defines the maximum size of packets, any packet size larger
than the value will be fragmented. If you have decreased this value and
experience high packet error rates, you can increase it again, but it will
likely decrease overall network performance. Select a setting within a
range of 256 to 2346 bytes. Minor change is recommended.
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RTS / CTS Minimum packet size required for an RTS/CTS (Request To Send/Clear
to Send). For packets smaller than this threshold, an RTS/CTS is not
sent and the packet is transmitted directly to the WLAN. Select a
setting within a range of 0 to 2347 bytes. Minor change is
recommended.
Preamble The preamble defines the length of the CRC block for communication
among the wireless networks. There are two modes including Long and
Short. High network traffic areas should use the shorter preamble type.
MAC Address Filter This AP can protect from the unauthorized users by MAC Address
filtering. Please refer to Section 3.5.3.
Bridge Adapter Wireless adapters connect to the AP can access to the wired network
through the bridge adapter. You can select an Ethernet adapter in the
list be the bridge between the wireless and wired networks.
3.4.3 MAC Address Filter
Parameter Description
Filter Type Disable – Disable the MAC Address filter function.
Accept – Only the wireless adapters with the MAC Address setup in the
table can connect to the AP.
Reject – The wireless adapters with the MAC Address setup in the table
will be rejected to connect to the AP.
Filter MAC Address MAC Address is a unique identification for hardware devices in the
network. It is a 12-digit hexadecimal values.
There are fifty sets of MAC Address can setup in the table. Fill the
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MAC Addresses of wireless adapters you want to accept or reject to
access the AP in this table.
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4 Troubleshooting
This chapter provides solutions to problems usually encountered during the installation and
operation of the adapter.
1. What is the IEEE 802.11g standard?
802.11g is the new IEEE standard for high-speed wireless LAN communications that provides
for up to 54 Mbps data rate in the 2.4 GHz band. 802.11g is quickly becoming the next
mainstream wireless LAN technology for the home, office and public networks.
802.11g defines the use of the same OFDM modulation technique specified in IEEE 802.11a
for the 5 GHz frequency band and applies it in the same 2.4 GHz frequency band as IEEE
802.11b. The 802.11g standard requires backward compatibility with 802.11b.
The standard specifically calls for:
A. A new physical layer for the 802.11 Medium Access Control (MAC) in the 2.4 GHz
frequency band, known as the extended rate PHY (ERP). The ERP adds OFDM as a
mandatory new coding scheme for 6, 12 and 24 Mbps (mandatory speeds), and 18, 36, 48
and 54 Mbps (optional speeds). The ERP includes the modulation schemes found in
802.11b including CCK for 11 and 5.5 Mbps and Barker code modulation for 2 and 1 Mbps.
B. A protection mechanism called RTS/CTS that governs how 802.11g devices and 802.11b
devices interoperate.
2. What is the IEEE 802.11b standard?
The IEEE 802.11b Wireless LAN standard subcommittee, which formulates the standard for
the industry. The objective is to enable wireless LAN hardware from different manufactures to
communicate.
3. What does IEEE 802.11 feature support?
The product supports the following IEEE 802.11 functions:
z CSMA/CA plus Acknowledge Protocol
z Multi-Channel Roaming
z Automatic Rate Selection
z RTS/CTS Feature
z Fragmentation
z Power Management
4. What is Ad-hoc?
An Ad-hoc integrated wireless LAN is a group of computers, each has a Wireless LAN adapter,
Connected as an independent wireless LAN. Ad hoc wireless LAN is applicable at a
departmental scale for a branch or SOHO operation.
5. What is Infrastructure?
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An integrated wireless and wireless and wired LAN is called an Infrastructure configuration.
Infrastructure is applicable to enterprise scale for wireless access to central database, or
wireless application for mobile workers.
6. 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.
7. What is WEP?
WEP is Wired Equivalent Privacy, a data privacy mechanism based on a 40 bit shared key
algorithm, as described in the IEEE 802 .11 standard.
8. What is TKIP?
TKIP is a quick-fix method to quickly overcome the inherent weaknesses in WEP security,
especially the reuse of encryption keys. TKIP is involved in the IEEE 802.11i WLAN security
standard, and the specification might be officially released by early 2003.
9. What is AES?
AES (Advanced Encryption Standard), a chip-based security, has been developed to ensure the
highest degree of security and authenticity for digital information, wherever and however
communicated or stored, while making more efficient use of hardware and/or software than
previous encryption standards. It is also included in IEEE 802.11i standard. Compare with
AES, TKIP is a temporary protocol for replacing WEP security until manufacturers implement
AES at the hardware level.
10. Can Wireless products support printer sharing?
Wireless products perform the same function as LAN products. Therefore, Wireless products
can work with Netware, Windows 2000, or other LAN operating systems to support printer or
file sharing.
11. 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 series offer the encryption function (WEP) to enhance security and
Access Control. Users can set it up depending upon their needs.
12. What is DSSS?What is FHSS?And what are their differences?
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Frequency-hopping spread-spectrum (FHSS) uses a narrowband carrier that changes frequency
in a pattern that is known to both transmitter and receiver. Properly synchronized, the net
effect is to maintain a single logical channel. To an unintended receiver, FHSS appears to be
short-duration impulse noise. Direct-sequence spread-spectrum (DSSS) generates a redundant
bit pattern for each bit to be transmitted. This bit pattern is called a chip (or chipping code).
The longer the chip is, the greater the probability that the original data can be recovered. Even
if one or more bits in the chip are damaged during transmission, statistical techniques
embedded in the radio can recover the original data without-the need for retransmission. To an
unintended receiver, DSSS appears as low power wideband noise and is rejected (ignored) by
most narrowband receivers.
13. What is Spread Spectrum?
Spread Spectrum technology is a wideband radio frequency technique developed by the
military for use in reliable, secure, mission-critical communication systems. It is designed to
trade off bandwidth efficiency for reliability, integrity, and security. In other words, more
bandwidth is consumed than in the case of narrowband transmission, but the trade off produces
a signal that is, in effect, louder and thus easier to detect, provided that the receiver knows the
parameters of the spread-spectrum signal being broadcast. If a receiver is not tuned to the right
frequency, a spread –spectrum signal looks like background noise. There are two main
alternatives, Direct Sequence Spread Spectrum (DSSS) and Frequency Hopping Spread
Spectrum (FHSS).