Topcom USB 4001G User Manual

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Full User Guide
CONTENTS
1.1 Features.........................................................................................................................2
1.2 Specifications................................................................................................................2
1.3 Package Contents..........................................................................................................3
3.1 Site Survey....................................................................................................................8
3.2 Profile............................................................................................................................ 9
3.2.1 Configure the Profile.....................................................................................10
3.2.1.1 Configuration ........................................................................................................10
3.2.1.2 Authentication and Security..................................................................................12
3.2.1.3 802.1x Setting-Certification..................................................................................16
3.2.1.4 802.1x Setting-CA Server .....................................................................................17
3.3 Link Status..................................................................................................................18
3.4 Statistics......................................................................................................................20
3.5 Advance ...................................................................................................................... 20
3.6 About...........................................................................................................................23
3.7 Turbo Mode.................................................................................................................23
1 Introduction
Thank you for purchasing the 802.11g Wireless LAN USB Adapter. This USB adapter is designed to comply with IEEE 802.11g Wireless LAN standard and easy to carry with the Mini size. It is suitable for any Laptop or Desktop computers.
This adaptor supports higher data throughput than the IEEE 802.11g standard (up to 54Mbps). It supports specific ways to increase the data transfer rate at a time; compress the data and decrease the waiting time to send the next data to the Routers or APs. This feature is called Turbo Mode. When the adaptor is connecting to the Routers or APs with the proprietary feature, the wireless network will be more effective.
For WLAN security issues, this adaptor supports 64/128-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. Furthermore, this adaptor supports WPA2 function, WPA2 provides a stronger encryption mechanism through AES (Advanced Encryption Standard), which is a requirement for some corporate and government users.
This adapter is cost-effective, together with the versatile features; it is the best solution for you to build your wireless network.
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1.1 Features
Complies with the IEEE 802.11b and IEEE 802.11g 2.4GHz (DSSS) standards.
High data transfer rate – up to 54Mbps.
Supports Turbo Mode to enhance the data transfer speed within the specific wireless
network.
Supports 64/128-bit WEP, WPA (TKIP with IEEE 802.1x), WPA2 (AES with IEEE
802.1x) functions for high level of security.
Supports the most popular operating system: Windows 98SE/Me/2000/XP/2003 Server.
Supports USB 2.0/1.1/1.0 interface.
Portable and mini-size design.
1.2 Specifications
Standards: IEEE 802.11b/g
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
Securities: 64/128-bit WEP Data Encryption, WPA (TKIP with IEEE 802.1x), WPA2
(AES with IEEE 802.1x)
Note: WPA2 is only enabled in Windows 2000/XP/2003 Server.
Antenna: Internal Antenna
Drivers: Windows 2000/XP/2003 Server
LEDs: Link/Activity
Transmit Power: 17dBm ± 2dBm
Receive Sensitivity: -70dBm@54Mbps, -83.5dBm@11Mbps
Dimension: 9(H) x 27(W) x 87(D) mm
Temperature: 32~122°F (0 ~ 50°C)
Humidity: 10-95% (NonCondensing)
Certification: FCC, CE
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1.3 Package Contents
Before you begin the installation, please check the items of your package. The package should include the following items:
One USB Adaptor
One CD (Driver/Utility/User’s Manual)
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2 Installation Procedure
Before you proceed with the installation, please notice following descriptions.
Note1: Please do not install the adaptor into your computer before installing the software
program from the CD.
Note2: The following installation was operated under Windows XP. (Procedures are similar for
Windows 2000/2003 Server.)
Note3: If you have installed the Turbo Wireless LAN USB Adaptor driver & utility before, please
uninstall the old version first.
A. Insert the Installation CD to your CD-ROM Drive. Choose “Install Software”
B. Click “Yes” to process the installation if you accept the license agreement.
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C. If you need the adaptor to operate with better performance, please choose the “Optimize for
performance” to enable the Tx Burst mode. Or you can choose “Optimize for Wi-Fi mode” to let the adaptor run in standard wireless network.
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D. The sy stem starts to install the soft ware of the adaptor. Please follo w the instructions of the
program to plug in the adaptor into the USB port of your computer. And the system will automatically detect the adaptor
E. Please click “Finish” to complete the installation.
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3 Configuration Utility
The Topcom Configuration Utility is a powerful application that helps you configure the USB adaptor and monitor the link status and the statistics during the communication process.
When the adaptor is installed, the configuration utility will be displayed automatically. This adaptor will auto connect to wireless device which has better signal strength and no wireless security setting.
The Topcom Configuration Utility appears as an icon on the system tray of Windows while the adaptor is running. You can open the utility by double-click on the icon.
In Windows XP, there is a “Windows Zero Configuration Tool” for you to setup wireless clients. If you want to switch to use Topcom configuration utility, please follow one of the ways as below.
Right click the icon in the system tray and select “Use Topcom Wireless LAN Configuration utility”.
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3.1 Site Survey
When you open the Topcom Configuration Utility, the system will scan all the channels to find all the access points/stations within the accessible range of your adaptor and automati c ally connect to the wireless device with the highest signal strength. From the “Site Survey”, all the networks nearby will be listed. You can change the connection to another networks or add one of the networks to your own profile list.
Parameter Description Available Networks This list shows all available wireless networks within range of your
adaptor. It also displays the information of the networks including the SSID, BSSID, Signal Strength, Channel, Encryption, Authentication and Network Type. If you want to connect to any networks on the list, double-click the item on the list, and the adaptor will automatically connect to the selected network.
Rescan Button Click “Rescan” button to collect the new information of all the
Connect Button
Add to Profile Button
wireless networks nearby.
Click “Connect” to connect to the selected network.
Add the selected network to Profiles list.
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3.2 Profile
The “Profiles List” is for you to manage the networks you connect to frequently. You are able to Add/Delete/Edit/Activate a profile.
Parameter Description Profiles List The profiles list display all the profiles and the relative settings of
the profiles including Profile Name, SSID, Channel, etc. This sign indicates the activated profile is been connecting.
This sign indicates the activated profile is not been
connecting.
Add/Delete/Edit Button
Activate Button Click “Activate” to connect to the selected profile. When a profile is
Click these buttons to add/delete/edit the selected profiles.
activated, the adaptor will be initially connected to the profile.
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3.2.1 Configure the Profile
3.2.1.1 Configuration
Parameter Description Profile Name Define a recognizable profile name for you to identify the different
networks.
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 adaptor and then only the device with the same SSID can interconnect to the adaptor. If you want to add the network nearby to the profile list, pull down the menu, all the networks will be listed for you to add one of them to the profile list.
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Parameter Description PSM (Power Saving Mode) The power saving function is only available when the network type
is in Infrastructure. CAM (Constantly Awake Mode) – The adaptor will always set in active mode.
PSM (Power Saving Mode) – Enable the adaptor in the power saving mode when it is idle.
Network Type Infrastructure – This operation mode requires the pre sen ce of an
TX Power If you want to lower the transmit power of the adaptor for saving the
Ad Hoc Wireless Mode When the adaptor is set in Ad Hoc (Peer to Peer Mode), you can
Preamble The preamble defines the length of the CRC block for
802.11 Access Point. All communication is done via the Access Point or Router.
Ad-Hoc – Select this mode if you want to connect to another wireless stations in the Wireless LAN network without through an Access Point or Router.
power of the system, you can select the lower percentages from the list. The lower power will cause the lower signal strength and the coverage range.
designate the wireless connection mode for the Ad Hoc network.
802.11 B only – This adaptor can be compatible with both 802.11g and 802.11b wireless stations. If there are only 802.11b wireless stations in the network, you can set the adaptor to this mode.
802.11 B/G mix – If you have a mix of 802.11b and 802.11g wireless stations in your network, it is recommended to set the adaptor to this mode. This mode is also the default setting.
802.11 G only – This adaptor can be compatible with both 802.11g and 802.11b wireless stations. If there are only 802.11g wireless stations in the network, you can set the adaptor to this mode.
communication among wireless devices. This option i s only active in the Ad Hoc network.
There are two modes including Auto and Long Preamble. If “Auto“ mode is selected, the adaptor will auto switch the preamble mode depending on the wireless devices the adaptor is connecting to.
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Parameter Description RTS Threshold Minimum packet size required for an RTS (Request To Send). For
packets smaller than this threshold, an RTS is not sent and the packet is transmitted directly to the wireless network. Select a setting within a range of 0 to 2347 bytes. Minor change is recommended.
Fragment Threshold 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.
Channel This setting is only available for Ad Hoc mode. Select the number
of the radio channel used for the networking. The channel setting should be the same with the network you are connecting to.
3.2.1.2 Authentication and Security
Parameter Description Authentication Type This setting has to be consistent with the wireless networks that
the adaptor intends to connect.
Open – No authentication is needed among the wireless network.
Shared – Only wireless devices using a shared key (WEP Key
identified) are allowed to connecting each other.
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Parameter Description Authentication Type LEAP – LEAP is a pre-EAP, Cisco-proprietary protocol, with many
of the features of EAP protocols. Cisco controls the ability of other vendors to implement this protocol, so it should be selected for use only when limited vendor choice for client, access-point, and server products is not a concern. When you have set up LEAP authentication, you have to enter the user name and password of your computer.
WPA – WPA provides a scheme of mutual authentication using either IEEE 802.1x/Extensible Authentication Protocol (EAP) authentication or pre-shared key (PSK) technology. It provides a high level of assurance to enterprises, small businesses and home users that data will remain protected and that only authorized users may access their networks. For enterprises that have already deployed IEEE 802.1x authentication, WPA offers the advantage of leveraging existing authentication databases and infrastructure.
WPA-PSK – It is a special mode designed for home and small business users who do not have access to network authentication servers. In this mode, known as Pre-Shared Key, the user manually enters the starting password i n their access point or gateway, as well as in each wireless stations in the network. WPA-PSK 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.
WPA2 – Like WPA, WPA2 supports IEEE 802.1x/EAP authentication or PSK technology. It also includes a new advanced encryption mechanism using the Advanced Encryption Standard (AES). AES is required to the corporate user or government users. The difference between WP A and WPA2 is that WPA2 provides data encryption via the AES. In contrast, WPA uses Temporal Key Integrity Protocol (TKIP).
WPA2-PSK – WPA2-PSK is also for home and small business. The difference between WPA-PSK and WPA2-PSK is that WPA2-PSK provides data encryption via the AES. In contrast, WPA-PSK uses Temporal Key Integrity Protocol (TKIP).
802.1x Setting When you have set the Authentication Type to Open, Shared, WPA or WPA2, you can also enable IEEE 802.1x setting to use the authentication server or certification server to authenticate client users.
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Parameter Description Encryption Mode None – Disable the encryption mode.
WEP – Enable the WEP Data Encryption. When the item is selected, you have to continue setting the WEP Encryption keys.
TKIP – TKIP (Temporal Key Integrity Protocol) changes the temporal key every 10,000 packets (a packet is a kind of message transmitted over a network.) This ensures much greater security than the standard WEP security.
AES – AES has been developed to 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.
Note: All devices in the network should use the same encryption method to ensure the communication.
WPA Pre-Shared Key The WPA-PSK key can be from 8 to 64 characters and can be
WEP Key (Key1 ~ Key4)
letters or numbers. This same key must be used on all of the wireless stations in the network.
The WEP keys are used to encrypt data transmitted in the wireless network. There are two types of key length: 64-bit and 128-bit. Select the default encryption key from Key 1 to Key 4 by selected the radio button.
Fill the text box by following the rules below. 64-bit – Input 10-digit Hex values (in the “A-F”, “a-f” and “0-9” range) or 5-digit ASCII characters (incl uding “a-z” and “0-9”) as the encryption keys. For example: “0123456aef“ or “test1”.
128-bit – Input 26-digit Hex values (in the “A-F”, “a-f” and “0-9” range) or 13-digit ASCII characters (including “a-z” and “0-9”) as the encryption keys. For example: “01234567890123456789abcdef“ or “administrator”.
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The IEEE 802.1X specification describes a protocol that can be used for authenticating both clients and servers on a network. The authentication algorithms and methods are those provided by the Extensible Authentication Protocol (EAP), a method of authentication that has been in use for a number of years on networks that provide Point-to-Point Protocol (PPP) support as many internet service providers and enterprises do.
When an AP acting as an authenticator detects a wireless station on the LAN, it sends an EAP-Request for the user's identity to the device. (EAP, or the Extensible Authentication Protocol, is an authentication protocol that runs before network layer protocols transmit data over the link.) In turn, the device responds with its identity, and the AP relays this identity to an authentication server, which is typically an external RADIUS server.
An example for MD5 Authentication
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RADIUS
Server
IEEE 802.1x
Access Client
RADIUS
Client
1
Access Point
2
(1) Client requests to login the network.
(2) Login with username,
password.
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Windows 2000 IAS (Internet Authentication
Service)
(3) Send username, password to RADIUS server.
(4) Approve or deny user
login to the LAN.
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3.2.1.3 802.1x Setting-Certification
Parameter Description Authentication Type The EAP authentication protocols this adaptor has supported are
included as follows. This setting has to be consistent with the wireless APs or Routers that the adaptor intends to connect.
PEAP &TTLS – PEAP and TTLS are similar and easier than TLS in that they specify a stand-alone authentication protocol be used within an encrypted tunnel. TTLS supports any protocol within its tunnel, including CHAP, MS-CHAP, MS-CHAPv2, PAP and EAP-MD5. PEAP specifies that an EAP-compliant authentication protocol must be used; this adaptor supports EAP-MSCHAP v2, EAP-TLS/Smart Card and Generic Token Card. The client certificate is optional required for the authentication.
TLS/Smart Card –TLS is the most secure of the EAP protocols but not easy to use. It requires that digital certificates be exchanged in the authentication phase. The server presents a certificate to the client. After validating the serve r’s certificate, the client presents a client certificate to the server for validation.
MD5-Challenge – MD5-Challenge is the easiest EAP Type. It requires the wireless station to enter a set of user name and password as the identity to RADIUS Server.
Session Resumption There are “Disabled”, “Reauthentication”, “Roaming”, “SameSsid”
and “Always” selections for you to choose whether to recovery the session in different status.
Identity Enter the name as the identity for the server.
Password
Use Client Certificate A client certificate is required for TLS, and is optional for TTLS and
Enter the password as the identity for the server.
PEAP. This forces a client certificate to be selected from the appropriate Windows Certificate Store and made available to the RADIUS server for certification.
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Parameter Description Tunneled Authentication
Protocol When the authentication type is PEAP or TTLS, select a protocol
to be used to build the encrypted tunnel.
Identity This is the protected user EAP Identity used for authentication.
The identity specified may contain up to 63 ASCII characters, is case sensitive and takes the form of a Network Access Identifier, consisting of <name of the user>@<user’s home realm>. The user’s home realm is optional and indicates the routing domain.
Password The password used for authentication. It may contain up to 63
ASCII characters and is case sensitive.
3.2.1.4 802.1x Setting-CA Server
Parameter Description Use Certificate Chain When the EAP authentication type such as TLS, TTLS or PEAP is
selected and required a certification to tell the client what server credentials to accept from the authentication server in order to verify the server, you have to enable this function.
Certificate Issuer Choose the server from the list to issue the certificate. If “Any
Trusted CA” is selected, any CA included in the list (provided by the Microsoft Certificate Store) is permitted.
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Parameter Description Allow Intermediate Certificates A server designates an issuer as a trusted root authority by
placing the issuer's self-signed certificate, which contains the issuer's public key, into the trusted root certification authority certificate store of the host computer. Intermediate or subordinate certification authorities are trusted only if they have a valid certification path from a trusted root certification authority.
Server Name Enter the authentication server name.
Server name must match exactly When selected, the server name must match exactly the server
name found on the certificate.
Domain name must end in specified name
When selected, the server name field identifies a domain. The certificate must use a server name belonging to this domain or to one of its sub-domains (e.g. zeelans.com, where the server is blueberry.zeelans.com) but it may be any name used in the certificate name field.
3.3 Link Status
From the “Link Status” option, you can view all the information of the network you are connecting to.
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Parameter Description Status Display the SSID and MAC ID of the network the adaptor is
connecting to.
Extra Info Display the link status.
Channel Display the number of the radio channel and the frequency used
for the networking.
Link Speed (Mbps) Display the transmission and reception rate of the network. The
maximum transmission rate is 54Mbps.
Throughput (Kbps) Display the speed of data transmitted and received.
Link Quality This bar indicates the quality of the link. The higher the
percentage, the better the quality.
dBm If you want to know the signal strength in the unit of dBm, select
this check box.
Signal Strength This bar shows the signal strength level. The highe r percentage
Noise Level Display the noise level in the wireless environment.
shown in the bar, the more radio signal been received by the adaptor. This indicator helps to find the proper position of the wireless device for quality network operation.
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3.4 Statistics
This option enables you to view the statistic information of the connection including transmit statistics and receive statistics. You may reset the counters by clicking ”Reset Counter”.
3.5 Advance
This option enables you to configure more advanced settings, for example: wireless mode, protection mode and etc.
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Parameter Description Wireless Mode 802.11 B/G mix – If you have a mix of 802.11b an d 802.11g
wireless stations in your network, it is recommended to set the adaptor to this mode. This mode is also the default setting.
802.11 B only – This adaptor can be co mp atible with both 802.11g and 802.11b wireless stations. If there are only 802.11b wireless stations in the network, you can set the adaptor to this mode.
802.11 G only – This ad aptor can b e compatible with both 802.11g and 802.11b wireless stations. If there are only 802.11g wireless stations in the network, you can set the adaptor to this mode.
Select Your Country Region Code The available channel differs from different countries. For example:
USA (FCC) is chan nel 1-11, Europe (ETSI) is channel 1-13. The operating frequency channel will be restricted to the country user located before importing. If you are in different country, you have to adjust the channel setting to comply the regulation of the country.
B/G Protection If you have a mix of 802.11 b and 802.11g wireless stations in the
network, it is recommended to enable the protection mechanism. This mechanism can decrease the rate of data collision between
802.11b and 802.11g wireless stations. Whe n the protection mode is enabled, the throughput of the adaptor will be a little lower due to many of frame traffic should be transmitted. Auto – Based on the status of the network and automatically disable/enable protection mode.
On – Always enabl e the protection mode.
Off – Always disable the protection mode.
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 the network, the shorter distance i s allo wed between the adaptor and the wireless stations.
When the wireless mode is “802.1 1 B only”, the maximum dat a rate is 11Mbps (11b) so that there are only “Auto/1/2/5.5/11Mbps” options you can select.
Tx BURST Tx Burst enables the adaptor to deliver better throughput in the
same period and environment.
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Parameter Description Enable TCP Window Size The TCP Window is the amount of data a sender can send on a
particular connection before it gets an acknowledgment back from the receiver that it has gotten some of it. When the Router or AP the adaptor is connecting to have set up the TCP Window, you can enable the parameter to meet the data size for the Router or AP connection. The larger TCP Window the better performance.
Fast Roaming at -70dBm When you want to fast roaming to the network nearby without
intercepting the wireless connection especially the adaptor is applied to the multimedia application or a voice call, you can enable the parameter. The adaptor will fast roaming to the near network when the receive sensitivity (signal strength) is lower to the value you have set up.
Turn Off RF Button If you want to turn off the radio of the adaptor temporarily, click this
button. To turn on the radio, click this button again.
CCX 2.0 CCX 2.0 (Cisco Compatible Extensions) is developed by Cisco for
the radio monitoring and fast roaming.
LEAP Turn on CCKM During normal operation, LEAP-enabled client devices mutually
authenticate with a new access point by performing a complete LEAP authentication, including communication with the main RADIUS server.
When you configure your wireless LAN for fast re-association, however, LEAP-enabled client devices roam from on e access point to another without involving the main server. Using Cisco Centralized Key Management (CCKM), an access point configured to provide Wireless Domain Services (WDS) t akes the place of the RADIUS server and authenticates the client so quickly that there is no perceptible delay in voice or other time-sensitive applications.
Enable Radio Measurement When this parameter is enabled, the Cisco AP can run the radio
monitoring through the associated CCX-compliant clients to continuously monitor the WLAN radio environment and discover any new APs that are transmitting beacons.
Non-Serving Channel Measurements
Limit xxx milliseconds (0-2000)
The Cisco AP can perform monitoring measurements through the CCX-compliant clients on the non-serving channels when this parameter is enabled.
It limits the channel measurement time. The default value is 250 milliseconds.
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3.6 About
By choosing this option, you can click the hyperlink to connect the website for the information of the wireless chipset vendor and review basic information about the Utility such as the Driver, Utility and EEPROM Version. The MAC Address of the adaptor is displayed in the screen as well.
3.7 Turbo Mode
This adaptor supports specific ways to increase the data transfer rate at a time; compress the data and decrease the waiting time to send the next data to the Routers or APs, this feature (known as Turbo Mode) enables higher throughput than IEEE 802.11g standard (Up to 54Mbps).
When the adaptor is connecting to the Routers or APs with the proprietary Turbo Mode feature, the Turbo Mode will be enabled automatically without any configuration.
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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?
802.1 1g is the new IEEE standard for hi gh-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 modulatio n schemes fou nd 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
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.
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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 devel oped 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 product s. 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 DSSSWhat is FHSSAnd what are their differences
Frequency-hopping spread-spectrum (FHSS) uses a narrowband carrier that chang es frequ ency 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 technique s 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.
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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 designe d 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 prod uces 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 altern atives, Direct Sequence Spread Spectrum (DSSS) and Frequency Hopping Spread Spectrum (FHSS).
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