wcf12 user guide 2.qxd

wcf12 user guide 2.qxd
Instant WirelessTM Series
Wireless
CompactFlash Card
Use this guide to install: WCF12
User Guide
COPYRIGHT & TRADEMARKS
Copyright © 2002 Linksys, All Rights Reserved. Instant Wireless is a trademark of
Linksys. Microsoft, Windows, and the Windows logo are registered trademarks of
Microsoft Corporation. All other trademarks and brand names are the property of their
respective proprietors.
LIMITED WARRANTY
Linksys guarantees that every Instant Wireless™ CompactFlash Card is free from physical defects in material and workmanship for one year from the date of purchase, when
used within the limits set forth in the Specifications section of this User Guide. If these
products prove defective during this warranty period, call Linksys Technical Support in
order to obtain a Return Authorization Number. BE SURE TO HAVE YOUR PROOF OF
PURCHASE AND A BARCODE FROM THE PRODUCT'S PACKAGING ON HAND WHEN
CALLING. RETURN REQUESTS CANNOT BE PROCESSED WITHOUT PROOF OF PURCHASE. When returning a product, mark the Return Authorization Number clearly on the
outside of the package and include a copy of your original proof of purchase. All customers located outside of the United States of America and Canada shall be held responsible for shipping and handling charges.
IN NO EVENT SHALL LINKSYS’S LIABILITY EXCEED THE PRICE PAID FOR THE PRODUCT FROM DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES RESULTING FROM THE USE OF THE PRODUCT, ITS ACCOMPANYING SOFTWARE, OR ITS DOCUMENTATION. LINKSYS DOES NOT OFFER REFUNDS FOR ANY
PRODUCT. Linksys makes no warranty or representation, expressed, implied, or statutory, with respect to its products or the contents or use of this documentation and all
accompanying software, and specifically disclaims its quality, performance, merchantability, or fitness for any particular purpose. Linksys reserves the right to revise or
update its products, software, or documentation without obligation to notify any individual or entity. Please direct all inquiries to:
Linksys P.O. Box 18558, Irvine, CA 92623.
FCC STATEMENT
This product has been tested and complies with the specifications 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 antenna
used for this transmitter must be installed to provide a separation distance of at least 20
centimeters from all persons and must not be co-located or operating in conjunction with
any other antenna or transmitter. This equipment generates, uses, and can radiate radio
frequency energy and, if not installed and used according to 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 is found 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:
•
•
•
•
Reorient or relocate the receiving antenna
Increase the separation between the equipment or devices
Connect the equipment to an outlet other than the receiver’s
Consult a dealer or an experienced radio/TV technician for assistance
UG-WCF12-052102NC JL
Instant WirelessTM Series
Table of Contents
Chapter 1: Introduction
Chapter 1: Introduction
The Wireless CompactFlash Card
Features
Package Contents
System Requirements
1
1
1
2
2
Chapter 2: Planning Your Wireless Network
Network Topology
Roaming
Ad-Hoc Versus Infrastructure Mode
3
3
3
4
Chapter 3: Installing the Wireless
CompactFlash Card
Before You Start
Configuration Utility with Driver Installation
Hardware Installation
Wireless CompactFlash Card
5
5
5
12
Chapter 4: The Wireless CompactFlash Card’s
Configuration Utility
Overview
Accessing the Configuration Utility
Using the Configuration Utility
14
14
14
16
Appendix A: Troubleshooting
Common Problems and Solutions
Frequently Asked Questions
24
24
24
Appendix B: Glossary
28
Appendix C: Specifications
Environmental
34
34
Appendix D: Warranty Information
35
Appendix E: Contact Information
36
The Wireless CompactFlash Card
Experience the same speed and ease of wireless networking with your
CompactFlash Type I ready personal digital assistant (PDA) as you do with your
laptop or desktop computer. The Wireless CompactFlash Card is a Type I
CompactFlash card that connects directly to your PDA. Just plug it in, and
you’re ready to share data, printers, or high-speed Internet access over your
existing wireless network. Plus, user-friendly software makes it a snap to set up.
The Wireless CompactFlash Card is not only easy to install and use, but also
powerful. Your PDA can send and receive data at speeds up to 11Mbps. A highpowered, built-in antenna keeps you connected at distances of up to 984 feet.
The Wireless CompactFlash Card is also versatile and easily configurable
through your PDA.
Features
•
•
•
•
•
•
•
Compatible with Windows CE 3.0 or Higher
Up to 11 Mbps, High-Speed Data Transfer Rates with Automatic Fallback
User-Friendly Software Provides Simple Installation and Configuration
Compliant with 802.11b, DSSS, 2.4GHz Standard
Supports up to 128-bit WEP Encryption Security
Free Driver Upgrades at www.linksys.com
Free Technical Support—24 Hours a Day, 7 Days a Week, Toll-Free US
Calls
• 1-Year Limited Warranty
1
Instant WirelessTM Series
Wireless CompactFlash Card
Chapter 2: Planning Your
Wireless Network
Network Topology
A wireless LAN is exactly like a regular LAN, except that each Personal
Digital Assistant (PDA) equipped with a Wireless CompactFlash Card can
connect to the network using no wires. All points (including PDAs) in a wireless LAN must be configured to share the same SSID and other wireless settings.
Figure 1-1
Package Contents
•
•
•
•
One Instant Wireless™ CompactFlash Card
One Setup CD-ROM including Drivers and User Guide
One Quick Installation
One Registration Card
The Wireless CompactFlash Card provides LAN access for PDAs. An integrated wireless and wired LAN is called an infrastructure network. A group of
wireless users and an Access Point comprise a Basic Service Set (BSS). Each
PDA equipped with a Wireless CompactFlash Card in a BSS can talk to any
computer in a wired LAN infrastructure via the Access Point. The Wireless
CompactFlash Card also allows you to synchronize your PDA through a wireless connection.
An infrastructure network extends the accessibility of a Wireless CompactFlash
Card PDA to a wired LAN, and it doubles the effective wireless transmission
range for two Wireless CompactFlash Card PDAs. Since the Access Point is
able to forward data within its BSS, the effective transmission range in an infrastructure LAN is doubled.
System Requirements
•
•
•
One Computer with the following:
•
Pentium Class 200MHz or Faster Processor
•
CD-ROM Drive
•
64MB RAM (recommended)
•
Windows 98, Me, 2000, or XP (to load drivers)
Microsoft ActiveSync Utility
PDA with Windows CE 3.0 or Higher and Available Type I CompactFlash
Slot
The use of a unique ID in a BSS is essential.
The wireless LAN infrastructure configuration is appropriate for enterprisescale, wireless access to a central database, or as a wireless application for
mobile users.
Roaming
Infrastructure mode also supports roaming capabilities for mobile users. More
than one BSS can be configured to work as an Extended Service Set (ESS).
This continuous network allows users to roam freely within an ESS. All
Wireless CompactFlash Card PDAs within one ESS must be configured with
the same SSID and other wireless settings.
Optimum position for the Access Point is recommended. Proper Access Point
positioning combined with a clear radio signal will greatly enhance performance.
2
3
Instant WirelessTM Series
Ad-Hoc versus Infrastructure Mode
Unlike wired networks, wireless networks have two different modes in which
they may be set up: Infrastructure and Ad-Hoc. Choosing between these two
modes depends on whether or not the wireless network needs to share data or
peripherals with a wired network or not.
If the computers on the wireless network need to be accessed by a wired network or need to share a peripheral, such as a printer, with the wired network
computers, the wireless network should be set up in Infrastructure mode. (See
Figure 2-1.) The basis of Infrastructure mode centers around an access point,
which serves as the main point of communications in a wireless network.
Access points transmit
data to PCs equipped with
wireless network cards,
which can roam within a
certain radial range of the
access point. Multiple
access points can be
arranged to work in succession to extend the
roaming range, and can be
set up to communicate
with your Ethernet hardFigure 2-1
ware as well.
If the wireless network is relatively small and needs to share resources only
with the other computers on the wireless network, then the Ad-Hoc mode can
be used. (See Figure 2-2.) Ad-Hoc mode allows computers equipped with wireless transmitters and receivers to communicate directly with each other, eliminating the need for an access point. The drawback of this mode is that, in AdHoc mode, wireless-equipped computers are not able to communicate with
computers on a
wired
network.
And, of course,
communication
between the wireless-equipped
computers is limited by the distance
and interference
directly between
Figure 2-2
them.
4
Wireless CompactFlash Card
Chapter 3: Installing the
Wireless CompactFlash Card
Before You Start
The Wireless CompactFlash Card comes with an automated software installation procedure that interacts with the Windows operating system on your PC
and the Windows CE operating systems on your PDA. This procedure automatically installs the Configuration Utility with the driver. After installing the
software, you will install the hardware on your PDA.
Note: Do NOT insert the Wireless CompactFlash Card into the PDA.
You must install the Configuration Utility with driver first.
Configuration Utility with Driver Installation
1. Connect your PDA to your PC. Make sure you have the Microsoft
ActiveSync Utility installed on your PC. Insert the Setup CD-ROM into
your PC’s CD-ROM drive. Unless you have deactivated the auto-run feature
of Windows, the screen in Figure 3-1 should appear automatically.
Figure 3-1
If this screen does not appear automatically, you can access it by clicking
the Start button and choosing Run. In the drop-down box provided, type
d:\setup.exe (if “d” is the letter of your CD-ROM drive). Alternately, double-click My Computer, and then double-click the CD-ROM drive where
the Setup CD is located. Double-click the Setup.exe icon that appears.
5
Instant WirelessTM Series
2. Click the Setup button.
3. When you see the screen in Figure 3-2, click the Next button.
Figure 3-2
If, for whatever reason, you need to abort or terminate the installation, click
the Cancel button. Otherwise the installation will proceed.
Note: If you stop the installation before it has finished, you will have to
run the installation again before installing your hardware.
Wireless CompactFlash Card
4. When you see the License Agreement screen, read the entire policy by
clicking the Page Down button on your keyboard. Click the Yes button if
you agree, or No if you disagree. Clicking No will terminate the installation. If you click Yes, the installation will proceed.
Figure 3-3
5. You will determine where the Wireless CompactFlash Configuration Utility
will be installed. If you would like the utility files installed in the default
directory, click the Next button. If you would like to choose an alternate
directory, click the Browse button, and select the appropriate folder. Then
click the Next button.
Figure 3-4
6
7
Instant WirelessTM Series
Wireless CompactFlash Card
6. Choose either Infrastructure mode or Ad-Hoc mode, depending on your
needs. If you are unsure whether to choose Infrastructure or Ad-Hoc, refer
to “Chapter 2: Planning Your Wireless Network” for more information.
Once you have made your choice, click the Next button.
7b. Enter your wireless network’s SSID. The SSID must be identical for all
points in the network. The default setting is linksys (all lowercase). Enter
this information, and click the Next button.
Figure 3-5
Figure 3-7
7a. If you chose Infrastructure Mode, go to Step 7b now. If you chose AdHoc Mode, select the correct operating channel that applies to your network. The channel you choose should be the same as the channel for the
other computers and devices in your wireless network. Channel 6 is the
default. Select the appropriate channel, and click the Next button.
8. At this point, the Wizard will ask you to review your settings before copying files. Select Back to review or change any settings or Next if you are
satisfied with your settings.
Figure 3-8
Figure 3-6
8
9
Instant WirelessTM Series
9. The screen shown in Figure 3-9 will be displayed while the Configuration
Utility with driver is being installed.
Wireless CompactFlash Card
12. When you see the screen in Figure 3-12, check your PDA to see if additional steps are required. Follow the steps requested by your PDA. Once this
is done, or if none are requested, click the OK button.
Figure 3-12
13. When the installation is complete, click the Exit button.
Figure 3-9
10. Windows will ask if you wish to install the driver in the default directory.
Click the Yes button to use the default directory. Click the No button to
select a different directory.
Figure 3-10
Figure 3-13
11. The screen shown in Figure 3-11 will be displayed while the driver is being
installed.
The Setup Wizard has finished.
Proceed to the Hardware Installation section on the next page.
Figure 3-11
10
11
Instant WirelessTM Series
Wireless CompactFlash Card
Hardware Installation
1. Insert the Wireless CompactFlash Card into your PDA.
Figure 3-14
2. The screen in Figure 3-15 will appear. The default setting is Use serverassigned IP address. In most cases, you should keep the default setting.
However, if you are using fixed IP addresses on your wireless network, then
click the radio button next to Use specific IP address, and complete the IP
address, Subnet mask, and Default gateway fields.
3. Click the OK button to close this screen.
Figure 3-15
The installation of the Wireless CompactFlash Card is complete.
Proceed to “Chapter 4: The Wireless CompactFlash Card’s
Configuration Utility” if you wish to further customize
its configuration.
12
13
Instant WirelessTM Series
Wireless CompactFlash Card
The second icon, shown in Figure 4-2, is located in the system
tray on your PDA (see Figure 4-3). If you click the system tray
icon, you will see Figure 4-4. Select one of the following menu
choices:
Chapter 4: The Wireless
CompactFlash Card’s
Configuration Utility
Figure 4-2
Wireless Radio On Activates the
Wireless CompactFlash Card.
Overview
The Configuration Utility is provided to allow you further customization of
the Wireless CompactFlash Card. The Utility has five screens available:
• Link - The Link screen provides current information about the link between
the Wireless CompactFlash Card and the wireless network.
• Configuration - The Configuration screen gives you access to the Wireless
CompactFlash Card’s general settings.
• Encryption - The Encryption screen lets you alter the Wired Equivalent
Privacy (WEP) encryption settings.
• Site Survey - The Site Survey screen displays information about the Access
Points the Wireless CompactFlash Card detects in its vicinity.
• About - The About screen displays release information for the driver,
Configuration Utility, and firmware.
Wireless Radio Off Deactivates the
Wireless CompactFlash Card.
Remove Status Icon Deletes the
Utility icon from the PDA’s system
tray.
Wireless Network Status Click here
to access the Configuration Utility’s
Link tab.
Advanced Configuration Click
here to access the Configuration
Utility’s Configuration tab.
WEP Encryption Click here to
access the Configuration Utility’s
Encryption tab.
Figure 4-3
Version Information Click here to view the
Configuration Utility’s About tab.
Accessing the Configuration Utility
After the Configuration Utility has been installed,
you have two icons available for accessing the
Utility. Use either icon.
Site Survey Click here to access the
Configuration Utility’s Site Survey tab.
To use the first icon, click Start and then
Programs. Click the Wireless CF Card Monitor
icon to access the Utility.
Figure 4-4
Figure 4-1
14
15
Instant WirelessTM Series
Wireless CompactFlash Card
Using the Configuration Utility
State The State field displays MAC address information about the Access
Point with which the Wireless CompactFlash Card is communicating.
Use the various screens to customize the Wireless CompactFlash Card’s settings. Click the tab of the screen you wish to view.
Current Channel The Current Channel field shows the channel setting of the
Wireless CompactFlash Card.
LINK
Current Tx Rate The Current Tx Rate field shows the transfer rate in
megabits per second.
The Link screen provides information about the current link between the
Wireless CompactFlash Card and the wireless network. You cannot make any
changes using this screen.
Disable Radio Click this button to turn off the Wireless CompactFlash Card.
Rescan Click the Rescan button to refresh the information displayed on the
Link screen.
Throughput The Throughput fields show the rates at which data is transferred
and received in bytes per second.
Link Quality The Link Quality field displays a bar indicating the link’s quality. The higher the percentage, between 0 and 100 percent, the better the link.
Signal Strength The Signal Strength field displays a bar indicating the signal
strength. The higher the percentage, between 0 and 100 percent, the stronger
the signal.
Figure 4-5
16
17
Instant WirelessTM Series
CONFIGURATION
The Configuration screen allows you to change the Wireless CompactFlash
Card’s general settings.
Wireless CompactFlash Card
to-peer network and allows the sharing of local resources only between wireless-equipped PDAs and PCs—no use of an Access Point. The Infrastructure
mode allows a wireless network to be integrated into an existing wired network
by using an Access Point. Infrastructure networks permit roaming between
Access Points.
SSID An acronym for Service Set Identifier, SSID is the unique name shared
among all computers and other devices in a wireless network. The SSID setting
must be identical for all devices in the wireless network. It is case-sensitive and
must not exceed 32 alphanumeric characters.
Transmit Rate The Transmit Rate field shows the current transfer rate for the
Wireless CompactFlash Card. To optimize performance and range, select Fully
Automatic from the drop-down menu, so the Wireless CompactFlash Card will
automatically adjust the transfer speed for best performance and longest range.
Power Save Enabled This option allows your PDA to enter “sleep” mode if
your network connection experiences more than one second of no network
activity. This feature depends on your PDA’s power-saving mode.
Preamble Type The preamble defines the length of the CRC block for communication between the Wireless CompactFlash Card and an Access Point. All
wireless devices on your network must use the same preamble type. The default
is Long Preamble.
Ad-Hoc Channel The Ad-Hoc Channel setting specifies the channel used for
wireless communications and must be set to the same channel as the other computers and devices of the wireless network. This setting can only be adjusted if
the Wireless CompactFlash Card is set to Ad-Hoc mode.
Figure 4-6
To undo any changes, click the Undo button. To use the default settings and
eliminate those changes you’ve already made, click the Default button. To save
all of your changes, click the Apply button. To save all of your changes and
close the Configuration Utility, click the OK button at the top of the screen.
Profile You can save any of your configuration settings by setting up a Profile.
To do this, type the profile’s name in the Profile field, and click the Apply button to save your changes under that profile. You can also select a profile from
the drop-down menu.
Mode From the drop-down menu, choose between Infrastructure or Ad-Hoc,
depending on your network type. The Ad-Hoc mode is used for a simple peer18
19
Instant WirelessTM Series
Wireless CompactFlash Card
Encryption (WEP) You have three choices: Disabled, 64-bit, or 128-bit WEP
encryption. Select the option you wish to use.
ENCRYPTION
The Encryption screen allows you to customize security settings. Use this
screen to generate 64-bit or 128-bit WEP keys.
If you enable WEP encryption, then you can choose to create the encryption
keys using a passphrase or create the encryption keys manually.
Create Keys with Passphrase The Passphrase can be any text string with a
maximum of 31 alphanumeric characters.
Note: Creating and using the passphrase is recommended for easy
WEP configuration and security purposes.
Create Keys Manually Click Alphanumeric if you are using an alphanumeric phrase, or click Hexadecimal if you are using a hexadecimal number. Enter
an alphanumeric phrase or hexadecimal number for each key that you wish to
encrypt. (Hexadecimal numbers are comprised of numbers 0-9 and letters A-F.)
Make sure that the values entered in these key fields are identical to the encryption keys used on the other wireless devices in the network.
Once you have chosen your key encryption method and entered either the
Passphrase or Manual Key(s), click the Apply button to save your changes or
Undo to delete them. To save your changes and close the Configuration Utility,
click the OK button.
Important: All the devices in your wireless network must have identical keys, so they can communicate with each other.
Figure 4-7
An acronym for Wired Equivalent Privacy, WEP is an encryption scheme used
to protect your wireless data communications. WEP uses a combination of 64bit or 128-bit keys to control network access and provide encryption security
for every data transmission. To decode a data transmission, each point (device)
in a network must use an identical 64-bit or 128-bit key. Higher encryption levels mean higher levels of security, but, due to the complexity of the encryption,
they may mean decreased network performance.
20
21
Instant WirelessTM Series
Wireless CompactFlash Card
SITE SURVEY
ABOUT
The Site Survey screen lists the Access Points the Configuration Utility is able
to detect. It also displays each Access Point’s Network Name, MAC Address,
Signal Strength, and Network Type.
The About screen shows the release information for the Network Driver,
Configuration Utility, and NIC Firmware.
Figure 4-9
Figure 4-8
Help Click this button for more information about the Site Survey features.
Scan Click this button to search for Access Points.
22
23
Instant WirelessTM Series
Appendix A: Troubleshooting
Common Problems and Solutions
What is Ad-Hoc?
An ad-hoc wireless LAN is a group of computers, each with a WLAN card,
connected as an independent wireless LAN. Ad-hoc wireless LAN is applicable at a departmental scale for a branch or SOHO operation.
This chapter provides solutions to problems that may occur during the installation and operation of the Wireless CompactFlash Card. Read the descriptions
below to solve your problems. If you can’t find an answer here, check the
Linksys website at www.linksys.com.
What is Infrastructure?
An integrated wireless and wired LAN using an access point is called an
Infrastructure network. Infrastructure is applicable to enterprise scale for wireless access to central database, or as a wireless application for mobile workers.
1. My PDA does not recognize the Wireless CompactFlash Card.
• Make sure that the Wireless CompactFlash Card is properly inserted into the
CompactFlash port.
• Make sure the Link LED is solidly lit.
What is Roaming?
Roaming is the ability of a portable computer user to communicate continuously while moving freely throughout an area greater than that covered by a single Access Point. Before using the roaming function, the workstation must
make sure that it is set to the same channel number with the Access Point of the
dedicated coverage area.
2. The Wireless CompactFlash Card does not work properly.
• Reinsert the Wireless CompactFlash Card into the PDA’s CompactFlash port.
• Uninstall the utility and driver software from your PC and PDA device.
• Restart your PC, and repeat the software and hardware installation as specified in this User Guide.
3. I cannot communicate with the Access Point in the Infrastructure network.
• Make sure that the Access Point is powered on.
• Make sure that your Wireless CompactFlash Card is configured with the
same channel, SSID, and WEP settings as the Access Point.
Frequently Asked Questions
What is the IEEE 802.11b standard?
It is the IEEE standard for wireless networks. This standard allows wireless
LAN hardware from different manufacturers to communicate.
What IEEE 802.11b features are supported?
The product supports the following IEEE 802.11b functions:
• CSMA/CA plus Acknowledge protocol
• Multi-Channel Roaming
• Automatic Rate Selection
• RTS/CTS feature
• Fragmentation
• Power Management
24
Wireless CompactFlash Card
To achieve true seamless connectivity, the wireless LAN must incorporate a
number of different functions. Each node and Access Point, for example, must
always acknowledge receipt of each message. Each node must maintain contact
with the wireless network even when not actually transmitting data. Achieving
these functions simultaneously requires a dynamic RF networking technology
that links Access Points and nodes. In such a system, the user’s end node undertakes a search for the best possible access to the system. First, it evaluates such
factors as signal strength and quality, as well as the message load currently
being carried by each Access Point and the distance of each Access Point to the
wired backbone. Based on that information, the node next selects the right
Access Point and registers its address. Communications between end node and
host computer can then be transmitted up and down the backbone.
As the user moves on, the end node’s RF transmitter regularly checks the system to determine whether it is in touch with the original Access Point or
whether it should seek a new one. When a node no longer receives acknowledgment from its original Access Point, it undertakes a new search. Upon finding a new Access Point, it then re-registers, and the communication process
continues.
What is the 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.
25
Instant WirelessTM Series
Wireless CompactFlash Card
What is the ESS ID?
An Infrastructure network could also support roaming capability for mobile
workers. More than one BSS can be configured as an Extended Service Set
(ESS). Users within an ESS can roam freely between BSSs while being served
a continuous connection to the network wireless stations, and Access Points
within an ESS must be configured with the same ESS ID and the same radio
channel.
Would the wireless network’s information be intercepted while transmitting
through the air?
WLAN features two-fold protection in security. On the hardware side, as with
Direct Sequence Spread Spectrum technology, it has the inherent security feature of scrambling. On the software side, WLAN offers the encryption function
(WEP) to enhance security and access control. Users can set it up depending
upon their needs.
What is the ISM band?
The FCC and their counterparts outside of the U.S. have set aside bandwidth
for unlicensed use in the ISM (Industrial, Scientific and Medical) band.
Spectrum in the vicinity of 2.4 GHz, in particular, is being made available
worldwide.
Can Instant WirelessTM products support printer sharing?
Instant WirelessTM products perform the same function as LAN products.
Therefore, Instant Wireless products can work with NetWare, Windows 2000,
or other LAN operating systems to support printer or file sharing.
What is Spread Spectrum?
Spread Spectrum technology is a wideband radio frequency technique 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).
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 802.11b standard.
What is DSSS? What is FHSS? And what are their differences?
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, 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.
26
27
Instant WirelessTM Series
Wireless CompactFlash Card
Appendix B: Glossary
Default Gateway - The routing device used to forward all traffic that is not
addressed to a station within the local subnet.
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.
Driver - A software module that provides an interface between a network interface card and the upper-layer protocol software running in the computer.
Backbone - The part of a network that connects most of the systems and networks together and handles the most data.
Bandwidth - The transmission capacity of a given facility, in terms of how
much data the facility can transmit in a fixed amount of time; expressed in bits
per second (bps).
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 for 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).
Bit - A binary digit. The value—0 or 1—used in the binary numbering system.
Also, the smallest form of data.
Encryption - A security method that applies a specific algorithm to data in
order to alter the data's appearance and prevent other devices from reading the
information.
BSS (Basic Service Set) - An infrastructure network connecting wireless
devices to a wired network using a single access point.
ESS (Extended Service Set) - A set of more than two or more BSSs (multiple
access points) forming a single network.
CompactFlash - A flash memory format card that plugs into a CompactFlash
socket or into a standard Type II PC Card slot with an adapter.
Ethernet - IEEE standard network protocol that specifies how data is placed
on and retrieved from a common transmission medium. Having a transfer rate
of 10 Mbps., this forms the underlying transport vehicle used by several upperlevel protocols.
CRC (Cyclic Redundancy Checking) - Technique used to check for errors in
data transmissions.
CSMA/CD (Carrier Sense Multiple Access/Collision Detection) - The LAN
access method used in Ethernet. When a device wants to gain access to the network, it checks to see if the network is quiet (senses the carrier). If it is not, it
waits a random amount of time before retrying. If the network is quiet and two
devices access the line at exactly the same time, their signals collide. When the
collision is detected, they both back off and each wait a random amount of time
before retrying.
CTS (Clear To Send) - An RS-232 signal sent from the receiving station to the
transmitting station that indicates it is ready to accept data.
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.
Firmware - Code that is written onto read-only memory (ROM) or programmable read-only memory (PROM). Once firmware has been written onto the
ROM or PROM, it is retained even when the device is turned off.
Fragmentation - Breaking a packet into smaller units when transmitting over
a network medium that cannot support the original size of the packet.
Database - A database is a collection of data that is organized so that its contents can easily be accessed, managed, and updated.
28
29
Instant WirelessTM Series
Hardware - Hardware is the physical aspect of computers, telecommunications, and other information technology devices. The term arose as a way to distinguish the “box” and the electronic circuitry and components of a computer
from the program you put in it to make it do things. The program came to be
known as the software.
IEEE - The Institute of Electrical and Electronics Engineers. The IEEE
describes itself as “the world’s largest technical professional society—promoting the development and application of electrotechnology and allied sciences
for the benefit of humanity, the advancement of the profession, and the wellbeing of our members.”
LAN - A local area network (LAN) is a group of computers and associated
devices that share a common communications line and typically share
resources within a small geographic area (for example, within an office building).
MAC (Media Access Control) Address - A unique number assigned by the
manufacturer to any Ethernet networking device, such as a network adapter,
that allows the network to identify it at the hardware level.
Mbps (MegaBits Per Second) - One million bits per second; unit of measurement for data transmission.
The IEEE fosters the development of standards that often become national and
international standards. The organization publishes a number of journals, has
many local chapters, and several large societies in special areas, such as the
IEEE Computer Society.
Network - A system that transmits any combination of voice, video and/or data
between users.
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.
Passphrase - Used much like a password, a passphrase simplifies the WEP
encryption process by automatically generating the WEP encryption keys for
Linksys products.
IP Address - In the most widely installed level of the Internet Protocol (IP)
today, an IP address is a 32-binary digit number that identifies each sender or
receiver of information that is sent in packets across the Internet. When you
request an HTML page or send e-mail, the Internet Protocol part of TCP/IP
includes your IP address in the message (actually, in each of the packets if more
than one is required) and sends it to the IP address that is obtained by looking
up the domain name in the Uniform Resource Locator you requested or in the
e-mail address you're sending a note to. At the other end, the recipient can see
the IP address of the Web page requestor or the e-mail sender and can respond
by sending another message using the IP address it received.
ISM band - The FCC and their counterparts outside of the U.S. have set aside
bandwidth for unlicensed use in the ISM (Industrial, Scientific and Medical)
band. Spectrum in the vicinity of 2.4 GHz, in particular, is being made available worldwide. This presents a truly revolutionary opportunity to place convenient high-speed wireless capabilities in the hands of users around the globe.
30
Wireless CompactFlash Card
Packet - A unit of data routed between an origin and a destination in a network.
PC Card - A credit-card sized removable module that contains memory, I/O,
or a hard disk.
PDA (Personal Digital Assistant) - Any small mobile hand-held device that
provides computing and information storage and retrieval capabilities for personal or business use.
Plug-and-Play - The ability of a computer system to configure expansion
boards and other devices automatically without requiring the user to turn off
the system during installation.
Port - A pathway into and out of the computer or a network device. For example, the serial and parallel ports on a personal computer are external sockets for
plugging in communications lines, modems and printers.
Roaming - In an infrastructure mode wireless network, this refers to the ability to move out of one access point's range and into another and transparently
reassociate and reauthenticate to the new access point. This reassociation and
reauthentication should occur without user intervention and ideally without
interruption to network connectivity. A typical scenario would be a location
with multiple access points, where users can physically relocate from one area
to another and easily maintain connectivity.
31
Instant WirelessTM Series
RTS (Request To Send) - An RS-232 signal sent from the transmitting station
to the receiving station requesting permission to transmit.
Wireless CompactFlash Card
TX Rate - Transmission Rate.
Upgrade - To replace existing software or firmware with a newer version.
Software - Instructions for the computer. A series of instructions that performs
a particular task is called a “program.” The two major categories of software are
“system software” and “application software.” System software is made up of
control programs such as the operating system and database management system (DBMS). Application software is any program that processes data for the
user.
WEP (Wired Equivalent Privacy) - A data privacy mechanism based on a 64bit or 128-bit shared key algorithm, as described in the IEEE 802.11 standard.
A common misconception is that software is data. It is not. Software tells the
hardware how to process the data.
SOHO (Small Office/Home Office) - Market segment of professionals who
work at home or in small offices.
Spread Spectrum - Spread Spectrum technology is a wideband radio frequency technique 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).
Storage - The semi-permanent or permanent holding place for digital data.
Subnet Mask - The method used for splitting IP networks into a series of subgroups, or subnets. The mask is a binary pattern that is matched up with the IP
address to turn part of the host ID address field into a field for subnets.
Throughput - The amount of data moved successfully from one place to another in a given time period.
Topology - A network’s topology is a logical characterization of how the
devices on the network are connected and the distances between them. Most
large networks contain several levels of interconnection, the most important of
which include edge connections, backbone connections, and wide-area connections.
32
33
Instant WirelessTM Series
Appendix C: Specifications
Appendix D: Warranty
Information
Standards:
IEEE 802.11b, Type I CompactFlash
Channels:
11 Channels (US, Canada)
13 Channels (Europe)
14 Channels (Japan)
BE SURE TO HAVE YOUR PROOF OF PURCHASE AND A BARCODE
FROM THE PRODUCT’S PACKAGING ON HAND WHEN CALLING.
RETURN REQUESTS CANNOT BE PROCESSED WITHOUT PROOF OF
PURCHASE.
up to 196 ft. (60 m)
IN NO EVENT SHALL LINKSYS’ LIABILITY EXCEED THE PRICE PAID
FOR THE PRODUCT FROM DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES RESULTING FROM THE USE
OF THE PRODUCT, ITS ACCOMPANYING SOFTWARE, OR ITS DOCUMENTATION. LINKSYS DOES NOT OFFER REFUNDS FOR ANY PRODUCT.
Operating Range:
Indoors:
Outdoors:
up to 984 ft. (300 m)
Data Rate:
up to 11 Mbps (with automatic fallback)
LED:
Link
Environmental
34
Wireless CompactFlash Card
Dimensions:
2.37" x 1.70" x 0.13"
(60.2 mm x 43.2 mm x 3.3 mm)
Unit Weight:
0.63 oz. (0.018 kg)
Power:
3.3V DC, 300 mA
Certifications:
FCC Class B, CE Mark
Operating Temp.:
32ºF to 131ºF (0ºC to 55ºC)
Storage Temp.:
-3ºF to 139ºF (-20ºC to 65ºC)
Operating Humidity:
10% to 90% Non-Condensing
Storage Humidity:
10% to 95% Non-Condensing
LINKSYS OFFERS CROSS SHIPMENTS, A FASTER PROCESS FOR PROCESSING AND RECEIVING YOUR REPLACEMENT. LINKSYS PAYS
FOR UPS GROUND ONLY. ALL CUSTOMERS LOCATED OUTSIDE OF
THE UNITED STATES OF AMERICA AND CANADA SHALL BE HELD
RESPONSIBLE FOR SHIPPING AND HANDLING CHARGES. PLEASE
CALL LINKSYS FOR MORE DETAILS.
35
Instant WirelessTM Series
Appendix E: Contact Information
For help with the installation or operation of this product, contact Linksys
Technical Support at one of the phone numbers or Internet addresses below.
Sales Information
Technical Support
RMA Issues
Fax
Email
Web
FTP Site
800-546-5797 (LINKSYS)
866-242-8558
949-271-5461
949-265-6655
support@linksys.com
http://www.linksys.com
ftp.linksys.com
http://www.linksys.com
© Copyright 2002 Linksys, All Rights Reserved.
36
Was this manual useful for you? yes no
Thank you for your participation!

* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project

Download PDF

advertising