Wireless N USB Adapter User manual

 

TL-WN821N Wireless N USB Adapter Rev: 1.0.1 1910010060 COPYRIGHT & TRADEMARKS Specifications are subject to change without notice. is a registered trademark of TP-LINK TECHNOLOGIES CO., LTD. Other brands and product names are trademarks or registered trademarks of their respective holders. No part of the specifications may be reproduced in any form or by any means or used to make any derivative such as translation, transformation, or adaptation without permission from TP-LINK TECHNOLOGIES CO., LTD. Copyright 2008 TP-LINK TECHNOLOGIES CO., LTD. All rights reserved. http://www.tp-link.com FCC 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. the in accordance with This equipment generates, uses and can radiate radio frequency energy and, if not installed and used 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 or more of the following measures:

instructions, may cause harmful interference

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.

(2) This device must accept any interference received, including interference that may cause undesired operation. Changes or modifications to this unit not expressly approved by the party responsible for compliance could void the user's authority to operate the equipment. FCC RF Radiation Exposure Statement:

This equipment complies with FCC RF radiation exposure limits set forth for an uncontrolled environment. This device and its antenna must not be co-located or operating in conjunction with any other antenna or transmitter. This is a class B product. In a domestic environment, this product may cause radio interference, in which case the user may be required to take adequate measures. National Restrictions 2400.0-2483.5 MHz Country Restriction Reason/remark Bulgaria General authorization required for outdoor use and public service Outdoor use limited to 10 mW e.i.r.p. within the band 2454-2483.5 MHz Military Radiolocation use. Refarming of the 2.4 GHz band has been ongoing in recent years to allow current relaxed regulation. Full implementation planned 2012 France Italy Luxembourg None Norway Implemented If used outside of own premises, general authorization is required General authorization required for network and service supply(not for spectrum) This subsection does not apply for the geographical area within a radius of 20 km from the centre of Ny-lesund Russian Federation Only for indoor applications Note: Its not used outdoors in France. CONTENTS Package Contents .................................................................................................... 1 Chapter 1 Introduction........................................................................................... 2 1.1 Overview of the product .......................................................................................... 2 1.2 Features.................................................................................................................. 2 1.3 LED Status.............................................................................................................. 3 Chapter 2 Installation Guide.................................................................................. 4 2.1 Hardware Installation .............................................................................................. 4 2.2 Software Installation................................................................................................ 4 2.2.1 Overview ...................................................................................................... 4 2.2.2 Software Installation for Windows XP........................................................... 4 Chapter 3 Configuration for Windows XP .......................................................... 11 3.1 Current Status....................................................................................................... 11 3.2 Profile Management .............................................................................................. 13 3.2.1 Add or Modify a Configuration Profile......................................................... 13 3.2.2 Remove a profile ........................................................................................ 18 3.2.3 Switch another Profile ................................................................................ 19 3.2.4 Export a Profile........................................................................................... 19 3.2.5 Import a Profile........................................................................................... 19 3.2.6 Scan Available Networks............................................................................ 20 3.2.7 Auto Profile Selection Management ........................................................... 20 3.3 Diagnostics............................................................................................................ 22 3.3.1 Check Driver Information............................................................................ 22 3.3.2 Check Receive and Transmit Statistical Information .................................. 23 Chapter 4 Configuration for Windows Vista ...................................................... 24 Chapter 5 QSS configuration .............................................................................. 27 5.1 PBC (Push Button Configuration) method............................................................. 27 5.2 PIN method ........................................................................................................... 29 5.2.1 Enter a PIN into your AP device................................................................. 30 5.2.2 Enter the PIN from your AP device ............................................................ 31 Appendix A: Specifications................................................................................... 33 Appendix B: Glossary............................................................................................ 34 Package Contents The following contents should be found in your box:

One TL-WN821N Wireless N USB Adapter

One Quick Installation Guide

One USB cable

One Resource CD for TL-WN821N, including:

TL-WN821N Wireless Utility (TWCU) and Drivers User Guide

Note:

Make sure that the package contains the above items. If any of the listed items are damaged or missing, please contact with your distributor. Conventions:

The Adapter mentioned in this user guide stands for TL-WN821N Wireless N USB Adapter without any explanations. Chapter 1 Introduction TL-WN821N Wireless N USB Adapter Thank you for choosing TL-WN821N Wireless N USB Adapter. 1.1 Overview of the product Thank you for choosing the TL-WN821N Wireless N USB Adapter. The adapter is a draft 802.11n client device; it is designed to provide a high-speed and unrivaled wireless performance for your notebook and PC. With a faster wireless connection, you can get a better Internet experience, such as downloading, gaming, video streaming and so on. With the 802.11n technology, higher throughput improvements using MIMO (multiple input, multiple output antennas), the TL-WN821Ns auto-sensing capability allows high packet transfer rate of up to 300Mbps for maximum throughput. It has good capability on anti-jamming, it can also interoperate with other wireless (802.11b) products. The adapter supports WEP, WPA and WPA2 encryption to prevent outside intrusion and protect your personal information from being exposed. The TL-WN821N Wireless Utility helps you create a wireless connection immediately. With unmatched wireless performance, reception, and security protection, the TL-WN821N is the best choice for easily adding or upgrading wireless connectivity. 1.2 Features

Complies with IEEE802.11n (draft), IEEE802.11g, IEEE802.11b standards

Supports WPA/WPA2 data security, IEEE802.1x authentication, TKIP/AES encryption, WEP encryption

Supports high rate of up to 300Mbps for maximum throughput, supports automatically adjust to lower speeds due to distance or other operating limitations

Provides USB interface

Supports Ad-Hoc and Infrastructure modes

Good capability on anti-jamming

Supports roaming between access points when configured in Infrastructure mode

Ease to configure and provides monitoring information

Supports Windows 2000, XP and Vista.

Built-in two internal antennas which are listed in a format of 2x2 for two receivers and two transmitters. 2 1.3 LED Status TL-WN821N Wireless N USB Adapter Name Status Indication Status Blue On Slow flash Quick flash The adapter is trying to scan a networking connection. The adapter is already connected but is not transmitting or receiving data. The adapter is transmitting or receiving data. 3 Chapter 2 Installation Guide TL-WN821N Wireless N USB Adapter 2.1 Hardware Installation There are two ways to install the Adapter:

1. Plug the Adapter directly to the USB port on your computer. 2. Connect the Adapter and your computer through the USB cable attached in package. The LED will light up when the Adapter is installed successfully and the PC is on. 2.2 Software Installation 2.2.1 Overview The Adapters Setup Wizard will guide you through the Installation procedure for Windows XP. The Setup Wizard will install the TL-WN821N Wireless Utility (TWCU) and drivers. When you install the hardware prior to before installing the software, the system will prompt Found New Hardware Wizard, click Cancel, and run the Setup Wizard program on the CD-ROM. The Setup steps for Windows 2000 and XP are similar with each other. This user guide takes Windows XP for example. For the Setup steps in Windows Vista, please follow the clues of the screens. 2.2.2 Software Installation for Windows XP 1. Insert the Resource CD into your CD-ROM drive, and open the folder named TL-WN821N. To continue, double-click Setup.exe to load the following screen. 4 TL-WN821N Wireless N USB Adapter 2. Soon, Figure 2-2X will display after a moment. Click Next to continue. Figure 2-1 3. After that, you should choose a Setup type. It is recommended that you select Install Client Utilities and Driver. Select Install Driver Only to install driver only, select Make Figure 2-2 5 Driver Installation Diskette(s) to make the diskette(s) as the installation driver (shown in Figure 2-3). Click Next to continue. TL-WN821N Wireless N USB Adapter Figure 2-3 4. Click Browse to change the destination location for the software, then click Next in the screen below (shown in Figure 2-4). 6 TL-WN821N Wireless N USB Adapter Figure 2-4 5. After that, select the program folder, you should create a new folder name or select one from the Existing Folders list. It is recommended that you keep the default setting. Click Next to continue the installation. Figure 2-5 7 6. Choose configuration tool, if you are not sure, please leave it default. Then click Next to TL-WN821N Wireless N USB Adapter continue. 7. Click OK to continue the Installation on the screen below. Figure 2-6 8. Wait a while for the setup as shown in X Figure 2-8. Figure 2-7 8 TL-WN821N Wireless N USB Adapter Figure 2-8

Note:

1) For Windows XP, the Setup Wizard will notify you of how to proceed with the installation during these steps (shown in Figure 2-9X). Our drivers have been tested thoroughly, and are able to work with the operating system. Click Continue Anyway to continue the Installation. Figure 2-9 9. After all the steps above, you will see the screen below, click Finish to reboot the system. 9 TL-WN821N Wireless N USB Adapter Figure 2-10 10 Chapter 3 Configuration for Windows XP TL-WN821N Wireless N USB Adapter TP-LINK TL-WN821N can be configured by TL-WN821N Wireless Utility (TWCU) in Windows XP & 2000. This chapter describes how to configure your Adapter for wireless connectivity on your Wireless Local Area Network (WLAN) and use the data security encryption features. The configuration of the adapter in Windows XP is similar with that of Windows 2000. This User Guide takes Windows XP for example. For the configuration in Windows Vista, please refer to Chapter 4. After Installing the Adapter, the Adapters tray icon will appear in your system tray. It appears at the bottom of the screen, and shows the signal strength using color and the received signal strength indication (RSSI). If the icon is gray, there is no connection. If the icon is red, there is poor signal strength and the RSSI is less than 5dB. If the icon is yellow, there is poor signal strength and the RSSI is between 5dB and 10dB. If the icon is green, there is good signal strength and the RSSI is between 10dB and 20dB. If the icon is green, there is excellent signal strength and the RSSI is more than 20dB. Double-click the icon and the TWCU will run. You can also run the utility by clicking the Start BTL-WN821N Wireless Utility TL-WN821N Wireless Utility. The Program TP-LINK 3 TWCU provides some integrated and easy tools to:

Display current status information

Edit and add configuration profiles

Display current diagnostics information The section below introduces these above capabilities. 3.1 Current Status The Current Status tab contains general information about the program and its operations. The Current Status tab neednt any configurations. 11 0 TL-WN821N Wireless N USB Adapter The following table describes the items found on the Current Status screen. Figure 3-1

Profile Name - This shows the name of current selected configuration profile. The configuration of Profile name will be described on the General tab of Profile Management.

Link Status - This shows whether the station is associated to the wireless network.

Wireless Mode - Here displays the wireless mode.

Network Type - The type of network and the station currently connected are shown here. The options include:

Infrastructure (access point) Ad Hoc

Note:

Please configure the network type and wireless mode on the Advanced tab of Profile Management.

IP Address - This displays the computers IP address.

Control Channel - This shows the currently connected channel.

Data Encryption - Here displays the encryption type the driver is using. You can configure it on the Security tab of Profile Management.

Server Based Authentication - This shows whether the server based authentication is used. 12

Signal Strength - This shows the strength of the signal. TL-WN821N Wireless N USB Adapter Click Advanced on the screen above, you can see advanced information about the program and its operations. 3.2 Profile Management Click the Profile Management tab of the TWCU and the next screen will appear (shown in Figure 3-2X). The Profile Management screen provides tools to:

Add a new profile

Modify a profile

Remove a profile

Activate a Profile

Import a Profile

Export a Profile

Scan Available Networks

Order profiles 3.2.1 Add or Modify a Configuration Profile Figure 3-2 To add a new configuration profile, click New on the Profile Management tab. To modify a configuration profile, select the configuration profile from the Profile list and click Modify. Then 13 you will see the Management dialog box (shown in Figure 3-3). TL-WN821N Wireless N USB Adapter 1. Edit the General tab

Profile Name - Please enter the Profile name which identifies the configuration profile. This name must be unique. Note that the profile names are not case-sensitive.

Client Name - Please enter the Profile name which identifies the client machine.

Network Names (SSIDs) - Please enter the IEEE 802.11 wireless network name. This field has a maximum limit of 32 characters. 2. Edit the Security tab Figure 3-3 Select the Security tab in the screen above, and then you can edit the fields to configure the profile. To define the security mode, select the radio button of the desired security mode as follows. 14 TL-WN821N Wireless N USB Adapter Figure 3-4

WPA/WPA2: Wi-Fi Protected Access

WPA/WPA2 Passphrase: Wi-Fi Protected Access Passphrase

802.1x: Enables 802.1x security.

Pre-Shared Key (Static WEP): Enables the use of shared keys that are defined on both the access point and the station. To define shared encryption keys, choose the Shared Key radio button and click Configure to fill in the Define Shared Keys window (shown in Figure 3-5X).

None: No security (not recommended).

Note:

If the access point which the Adapter is associated has WEP set and the client has WEP enabled, make sure that Allow Association to Mixed Cells is checked on the HSecurity tabH to allow association. To complete WEP encryption configuration, you must select the 802.11 Authentication Mode as appropriate on the Advanced tab of this Profile Management dialog. To configure the Encryption Keys under the Pre-Shared keys (Static WEP) Security mode:

15 TL-WN821N Wireless N USB Adapter Figure 3-5

Note:

Select different Security Options, the configurations are different; you can select the appropriate security option and configure the exact key as your need. 3. Edit the Advanced tab This screen below allows you to make advanced configuration for the profile. 16 TL-WN821N Wireless N USB Adapter Figure 3-6

Power Save Mode - Please select the power save mode in the drop-down list. Maximum - Selects maximum mode to let the access point buffer incoming messages for the Adapter. The Adapter will detect the access point if any messages are waiting periodically. Normal - Normal mode uses maximum when retrieving a large number of packets, then switches back to power save mode after retrieving the packets. Off - Turns power saving off, thus powering up the Wireless USB Adapter continuously for a short message response time.

Network Type: There are basically two modes of networking:

Infrastructure - All wireless clients will connect to an access point or wireless router. Ad-Hoc - Directly connecting to another computer, for peer-to-peer communication, using wireless network adapters on each computer, such as two or more TL-WN821N wireless adapters.

Note:

1) An Infrastructure network contains an Access Point or wireless router. All the wireless devices or clients will connect to the wireless router or access point. 2) An Ad-Hoc network contains only clients, such as laptops with wireless desktop adapters. All the adapters must be in Ad-Hoc mode to communicate. 17

Wireless Mode: Specifies 2.4 GHz 300 Mbps, 2.4 GHz 54 Mbps or 2.4 GHz 11 Mbps operation in an access point network. The Wireless adapter must match the wireless mode of the access point with which it associates. TL-WN821N Wireless N USB Adapter

Wireless Mode when Starting an HAd HocH Network: Specifies 2.4 GHz 54/11 Mbps to start an Ad Hoc network if no matching network name is found after scanning all available modes. This mode also allows the selection of the channel that the Wireless Adapter uses. The channels available depend on the regulatory domain. If the adapter finds no other ad hoc adapters, the channel that the adapter starts the ad hoc network with will be selected automatically. The Adapter must match the wireless mode and channel of the clients it associates.

802.11 Authentication Mode: Select which mode the Adapter uses to authenticate to an access point:

Automatic causes the adapter to attempt authentication using shared, but switches it to open authentication if shared fails. Open System enables an adapter to attempt authentication regardless of its WEP settings. It will only associate with the access point if the WEP keys on both the adapter and the access point match. Shared-key only allows the adapter to associate with access points that have the same WEP key. For infrastructure (access point) networks, click Preferred APs to specify four access points at most to the client adapter that attempts to be associated to the access points. The four access points have different priorities; the frontal has the higher priority. Figure 3-7 3.2.2 Remove a profile 1. Go to the Profile Management tab (shown in XFigure 3-2X). 18 TL-WN821N Wireless N USB Adapter 2. Select the profile name in the Profiles List. 3. Click Remove.

Note:

The profile being used cant be removed. 3.2.3 Switch another Profile 1. Go to the Profile Management screen (shown in XFigure 3-2X). 2. Select the profile name required in the Profiles List. 3. Click Activate. 3.2.4 Export a Profile 1. From the Profile Management screen (shown in XFigure 3-2X), highlight the profile to export. 2. Click Export, the Export Profile window will then appear below. 3. Browse the directory to export the profile to. 4. Click Save. The profile should then be exported to the specified location. Figure 3-8 3.2.5 Import a Profile 1. From the Profile Management screen (shown in XFigure 3-2), click Import. Then the Import Profile will appear below. 2. Browse to the directory where the profile is located. 3. Highlight the profile name. 4. Click Open, the imported profile will then appear in the Profiles List. 19 TL-WN821N Wireless N USB Adapter 3.2.6 Scan Available Networks Figure 3-9 1. Click Scan on the Profile Management screen (shown in XFigure 3-2X), the Available Infrastructure and Ad Hoc Networks window will appear below. 2. Click Refresh to refresh the list at any time. 3. Highlight a network name and click Activate to connect to an available network. If no configuration profile exists for that network, the Profile Management window will open the General tab screen. Fill in the Profile name and click OK to create the configuration profile for that network. 3.2.7 Auto Profile Selection Management Figure 3-10 The auto selection feature allows the adapter to automatically select a profile from the list of 20 profiles and use it to connect to the network. To add a new profile into the Auto Selected Profiles list, please follow these steps. TL-WN821N Wireless N USB Adapter 1. On the Profile Management screen (shown in XFigure 3-2X), click Order Profiles. 2. The Auto Profiles Selection management window will appear (shown in Figure 3-11) with a list of all created profiles in the Available Profiles. Figure 3-11 3. Highlight the profiles to add to auto profile selection, and click Add. The profile will appear in the Auto Selected Profiles box. 4. Highlight a profile in the Auto Selected Profiles box. 5. Click Move Up or Move Down as appropriate.

Note:

The first profile in the Auto Selected Profiles box has highest priority, while the last profile has the lowest priority. 6. Click OK. 7. Check the Auto Select Profiles checkbox on the Profile Management tab (shown in Figure 3-2).

Note:

When auto profile selection is enabled by checking Auto Select Profiles on the Profile Management tab, the client adapter will scan for an available network. The profile with the highest priority and the same SSID as one of the found networks will be used to connect to the network. If the connection fails, the client adapter will try the next highest priority profile that 21 matches the SSID until an available network is found. TL-WN821N Wireless N USB Adapter 3.3 Diagnostics The Diagnostics tab of the TL-WN821N Wireless Utility (TWCU) provides buttons used to retrieve receiving and transmitting statistics. The Diagnostics tab does not require any configuration. The Diagnostics tab lists the following receiving and transmitting diagnostics for frames received or transmitted by the wireless network adapter:

Multicast frames transmitted and received

Broadcast frames transmitted and received

Unicast frames transmitted and received

Total bytes transmitted and received 3.3.1 Check Driver Information Figure 3-12 Click the Adapter Information button in the screen above, you will see the adapter information, including general information about the wireless network adapter and the Network Driver Interface Specification (NDIS) driver. Access the adapter information from the Diagnostics tab.

Card Name - The name of the wireless network adapter.

MAC Address - The MAC address of the wireless network adapter. 22

Driver - The driver name and path of the wireless network adapter driver. TL-WN821N Wireless N USB Adapter

Driver Version - The version of the wireless network adapter driver.

Driver Date - The creation date of the wireless network adapter driver.

Client Name - The name of the client computer. 3.3.2 Check Receive and Transmit Statistical Information The Advanced Statistics show receiving and transmitting statistical information about the following receiving and transmitting diagnostics for frames received by or transmitted to the wireless network adapter. Figure 3-13 23 Chapter 4 Configuration for Windows Vista TL-WN821N Wireless N USB Adapter After the Adapter's driver has been installed, Windows Vista will display a wireless Network Connection message like this one. Figure 4-1 means the connection has been established. Icon Icon connection. means there is no If the icon does not appear, please follow the steps below. If the icon still does not appear, the driver may be installed incorrectly or the adapter is unplugged, please try again. 1. Right-click the icon in your system tray, then click Connect to a network . Figure 4-2 2. The screen that appears will show you many available wireless networks. Highlight the network that you want, and then click Connect. 24 TL-WN821N Wireless N USB Adapter 3. To continue, click Connect Anyway. Click the Cancel button to end the Installation. Figure 4-3 4. After that, the installation will proceed as shown in Figure 4-5, click close. Figure 4-4 25 TL-WN821N Wireless N USB Adapter 5. The screen below will appear if the connection is successful. Figure 4-5 Figure 4-6 26 Chapter 5 QSS configuration TL-WN821N Wireless N USB Adapter QSS (Quick Secure Setup) function allows you to add a new wireless device to an existing network quickly. If the wireless card supports Wi-Fi Protected Setup (WPS), you can establish a wireless connection between wireless card and router using either Push Button Configuration (PBC) method or PIN method. First, the QSS software should be installed. Insert the Resource CD into your CD-ROM drive, Click the Start button and choose Run. In the field that appears, enter F:\TL-WN821N\QSS-821.exe

(Presume "F" is the letter of your CD-ROM drive) and click OK, then Figure 5-1 will appear. Figure 5-1 Then, please follow the clue of the Operation System to complete the QSS installation. After that, QSS function will run automatically. Here we will introduce two ways to configure the QSS

(For the configuration of QSS, here takes the Wireless Router of our company for example). 5.1 PBC (Push Button Configuration) method 1. Firstly, press the QSS button of the Router. There are two ways:

1) Press the QSS button directly on the front panel of the Router shown in Figure 5-2X. 27 TL-WN821N Wireless N USB Adapter Figure 5-2 2. Secondly, Double click the icon on the desktop to open the QSS Utility and then you can see the welcome screen shown as Figure 5-3. Click Next to continue. Figure 5-3 3. Thirdly, select Push the button on my access point in the next screen and click Next. 28 TL-WN821N Wireless N USB Adapter Figure 5-4 4. Then wait a minute until Figure 5-5 appears. Click Finish to complete the QSS configuration. Figure 5-5 5.2 PIN method There are two ways to configure the QSS by PIN method:

29 1) Enter a PIN into your AP device 2) Enter the PIN from your AP device. TL-WN821N Wireless N USB Adapter Following are the detailed configuration procedure of each way. 5.2.1 Enter a PIN into your AP device 1. Double click the icon on the desktop to open the QSS Utility and then you can see the welcome screen shown as Figure 5-3. Click Next to continue. Then Figure 5-6 will appear. Select the second option and you will see a PIN value displayed in the screen. Remember it and Click Next. Figure 5-6 2. Open the Routers Web-based Utility and click QSS link on the left of the main menu. Then Figure 5-7 will appear. Click Add device, then you can see Figure 5-8. Select Enter the new devices PIN and enter the PIN value shown in Figure 5-8X, click Connect. After that, wait for a minute until the following screens prompt that the devices connect successfully. 30 TL-WN821N Wireless N USB Adapter Figure 5-7 5.2.2 Enter the PIN from your AP device Figure 5-8 1. Open the QSS Utility and you will see Figure 5-5. Click Next to continue. Then Figure 5-10 will appear. Select the third option and enter the PIN value which is labeled on the bottom of the Router. Click Next. Figure 5-9 3. When Figure 5-7X appears, the QSS configuration is complete. 31

Note:

If you generate a new PIN code for your router, please enter the new one instead. TL-WN821N Wireless N USB Adapter 32 Appendix A: Specifications TL-WN821N Wireless N USB Adapter Normal Interface Standards USB 2.0 Interface IEEE802.11n (draft); IEEE802.11g; IEEE802.11b;

Operating System Windows 2000, XP and Vista Radio Data Rate Modulation 11b1/2/5.5/11Mbps 11g6/9/12/18/24/36/48/54Mbps 11nUp to 300Mbps 11b:CCK,QPSK,BPSK;

11g:OFDM;

11n: QPSK,BPSK,16-QAM,64-QAM Media Access Protocol CSMA/CA with ACK Transmit Power 19dBm (Maximal) Data Security WPA/WPA2; 64/128-bit WEP; TKIP/AES Frequency 2.4 ~ 2.4835GHz Spread Spectrum Direct Sequence Spread Spectrum (DSSS) Safety & Emissions FCC, CE Environmental and Physical Operating Temp. 0~40 (32 ~104

) Storage Temp.

-20 70 ( -4~158) Humidity 10% - 95% RH, Non-condensing 33 TL-WN821N Wireless N USB Adapter Appendix B: Glossary

802.11b - The 802.11b standard specifies a wireless product networking at 11 Mbps using direct-sequence spread-spectrum (DSSS) technology and operating in the unlicensed radio spectrum at 2.4GHz, and WEP encryption for security. 802.11b networks are also referred to as Wi-Fi networks.

802.11g - specification for wireless networking at 54 Mbps using direct-sequence spread-spectrum (DSSS) technology, using OFDM modulation and operating in the unlicensed radio spectrum at 2.4GHz, and backward compatibility with IEEE 802.11b devices, and WEP encryption for security.

802.11n - 802.11n builds upon previous 802.11 standards by adding MIMO (multiple-input multiple-output). MIMO uses multiple transmitter and HreceiverH antennas to allow for increased data throughput via spatial multiplexing and increased range by exploiting the spatial diversity, perhaps through coding schemes like Alamouti coding. The Enhanced Wireless Consortium

(EWC)H H was formed to help accelerate the IEEE 802.11n development process and promote a technology specification for interoperability of next-generation wireless local area networking (WLAN) products.

[3]

Ad-hoc Network - An ad-hoc network is a group of computers, each with a Wireless Adapter, connected as an independent 802.11 wireless LAN. Ad-hoc wireless computers operate on a peer-to-peer basis, communicating directly with each other without the use of an access point. Ad-hoc mode is also referred to as an Independent Basic Service Set (IBSS) or as peer-to-peer mode, and is useful at a departmental scale or SOHO operation.

DSSS - (Direct-Sequence Spread Spectrum) - DSSS generates a redundant bit pattern for all data transmitted. This bit pattern is called a chip (or chipping code). Even if one or more bits in the chip are damaged during transmission, statistical techniques embedded in the receiver can recover the original data without the need of retransmission. To an unintended receiver, DSSS appears as low power wideband noise and is rejected (ignored) by most narrowband receivers. However, to an intended receiver (i.e. another wireless LAN endpoint), the DSSS signal is recognized as the only valid signal, and interference is inherently rejected (ignored).

FHSS - (Frequency Hopping Spread Spectrum) - FHSS continuously changes (hops) the carrier frequency of a conventional carrier several times per second according to a pseudo-random set of channels. Because a fixed frequency is not used, and only the transmitter and receiver know the hop patterns, interception of FHSS is extremely difficult.

Infrastructure Network - An infrastructure network is a group of computers or other devices, each with a Wireless Adapter, connected as an 802.11 wireless LAN. In infrastructure mode, the wireless devices communicate with each other and to a wired network by first going through an access point. An infrastructure wireless network connected to a wired network is referred to as a Basic Service Set (BSS). A set of two or more BSS in a single network is referred to as an Extended Service Set (ESS). Infrastructure mode is useful at a corporation scale, or when it is necessary to connect the wired and wireless networks.

Spread Spectrum - Spread Spectrum technology is a wideband radio frequency technique 34 U U TL-WN821N Wireless N USB Adapter developed by the military for use in reliable, secure, mission-critical communications 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).

SSID - A Service Set Identification is a thirty-two character (maximum) alphanumeric key identifying a wireless local area network. For the wireless devices in a network to communicate with each other, all devices must be configured with the same SSID. This is typically the configuration parameter for a wireless PC card. It corresponds to the ESSID in the wireless Access Point and to the wireless network name. See also Wireless Network Name and ESSID.

WEP - (Wired Equivalent Privacy) - A data privacy mechanism based on a 64-bit or 128-bit or 152-bit shared key algorithm, as described in the IEEE 802.11 standard. To gain access to a WEP network, you must know the key. The key is a string of characters that you create. When using WEP, you must determine the level of encryption. The type of encryption determines the key length. 128-bit encryption requires a longer key than 64-bit encryption. Keys are defined by entering in a string in HEX (hexadecimal - using characters 0-9, A-F) or ASCII (American Standard Code for Information Interchange alphanumeric characters) format. ASCII format is provided so you can enter a string that is easier to remember. The ASCII string is converted to HEX for use over the network. Four keys can be defined so that you can change keys easily.

Wi-Fi - A trade name for the 802.11b wireless networking standard, given by the Wireless Ethernet Compatibility Alliance (WECA, see http://www.wi-fi.net), an industry standards group promoting interoperability among 802.11b devices.

WLAN - (Wireless Local Area Network) - A group of computers and associated devices communicate with each other wirelessly, which network serving users are limited in a local area.

WPA - (Wi-Fi Protected Access) - A wireless security protocol use TKIP (Temporal Key Integrity Protocol) encryption, which can be used in conjunction with a RADIUS server. 35