IEEE 802.11b User Guide
IEEE 802.11b 11Mbps
Wireless LAN USB Card
User’s Guide
Table of Contents
INTRODUCTION ............................................................. 4
About the Wireless LAN USB Card..................................5
Wireless LAN Basics........................................................6
Wireless LAN USB Card Operating Modes ................... 10
11 Mbps Operation......................................................... 10
Wireless LAN USB Card LED Descriptions...................11
HARDWARE INSTALLATION....................................... 12
Preparation..................................................................... 12
Installing the Wireless LAN USB Card...........................12
INSTALLING AND CONFIGURING.............................. 14
Installing the WLAN Driver in Windows 98.................... 14
Installing the Windows ME Driver .................................. 16
Installing the Driver in Windows 2000............................17
Verifying the Firmware Version...................................... 20
WIRELESS LAN USB CARD UTILITY ......................... 21
System ........................................................................... 23
Configuration..................................................................26
Profiles........................................................................... 30
Scanning for Access Points − Site Survey.....................37
Options...........................................................................39
About.............................................................................. 40
WIRELESS LAN USB CARD SPECIFICATION ........... 41
TROUBLESHOOTING .................................................. 43
Windows 95/98 Troubleshooting Tips............................ 43
Windows 2000 Troubleshooting Tips............................. 45
CUSTOMER SUPPORT................................................ 46
1
Introduction
The Wireless LAN USB Card is a Direct-Sequence Spread
Spectrum (DSSS) products. DSSS is a spread spectrum
network operating between 2.4 and 2.5 GHz. Spread
spectrum communication provides a high-capacity network
within large or small environments. DSSS products provide
a high-capacity network using multiple access points within
large or small environments.
Based on IEEE 802.11b, Wireless LAN products can
perform at speeds of up to 11 Mbps. This technology works
by using multiple frequencies in the 2.4 GHz range utilizing
Direct Sequence Spread Spectrum (DSSS) technology.
Designed to cover distances of up to 100 meters indoors and
300 meters outdoors, Wireless LAN (WLAN) technology lets
you access your network from anywhere within this radius.
The range of WLAN is limited by the number of walls,
ceilings, floors, or other objects the wireless signals must
pass through. Typical ranges vary depending upon the
types of materials and background RF noise in the WLAN
area.
WLAN products offer the following network features:
• WLAN bridging architecture allows communication
between wired network devices and mobile devices.
• WLAN products support the IEEE 802.11b and WiFi
specifications. This open architecture allows WLAN
devices to communicate with wireless devices from
other manufacturers that conform to the same
specifications.
• WLAN products allows mobile devices to roam
throughout large facilities while remaining connected
to the network.
• WLAN products allow establishment of ad-hoc wireless
workgroup networks.
• WLAN products are protocol-independent, allowing
mobile devices to communicate with a wide range of
servers, hosts and systems.
About the Wireless LAN USB Card
The Wireless LAN USB Card allows USB equipped host
systems to configure, connect to and establish a wireless
network. The Wireless LAN USB Card is fully compliant
with the USB version 1.1 standard.
Features Include:
• IEEE 802.11b compatibility providing wireless
Ethernet connectivity at speeds of up to 11 Mbps.
• Dynamic scaling of the connection speed between 11,
5.5, 2, and 1 Mbps to match the wireless network
conditions.
• Automatic data rate switching providing maximum
reliability, throughput and connectivity.
• Supports wireless data encryption with 64-bit and 128bit WEP standard for security.
• Dual ceramic antennas for antenna diversity to reduce
multi-path interference.
• PCMCIA type II form factor.
• Support for Windows 95, 98, NT4.0, 2000, ME, and XP.
• Simple setup and easy-to-use diagnostic utilities.
• FCC Part 15.247 (US), ETS 300 328 (Europe), ARIB
STD-T66 and RCR STD-33A (Japan) compliant.
• Multiple operating mode options for access point or
peer-to-peer associations.
• Low-power operation.
• In ESS (Infrastructure or 802.11 Station) mode, the
USB Card connects to an access point (AP). In ESS
mode, the USB Card can roam freely between access
point cells in the network or transmit and receive
across subnets. MUs appear as network nodes to other
devices in the network. ESS is the default mode for the
adapter.
• Use the IBSS (802.11 Ad Hoc) mode to form peer-topeer networks without access points. Use IBSS to
create networks where needed within established cells.
The MU starting the IBSS network (the first Wireless
LAN USB Card transmitting a beacon) determines the
channel and data rate used for the other adapters in
the IBSS network.
Wireless LAN Basics
In order to set up and use your Wireless LAN USB Card,
you should have some basic understanding of WLAN
Technology and the various functions of the device.
A wireless is a cellular computer network that uses radio
signals to establish network links.
Wireless LANs support the same network applications that
are used on wired Ethernet LANs. Wireless LAN USB
Cards can be used on laptop and desktop systems and
support the same protocols as Ethernet adapters. For most
users, there is no noticeable functional difference between a
wired Ethernet desktop computer and a WLAN workstation
other than the added benefit of being able to roam within
the WLAN.
A Wireless LAN (WLAN) Access Point provides a link
between the WLAN and the wired Ethernet network and its
resources. Servers, network printers, and Internet
connections can be accessed from Wireless workstations
through a WLAN Access Point.
Radio Transmission
WLAN devices use electromagnetic waves within a broad,
unlicensed range of the radio spectrum to transmit and
receive signals. When a wireless access point is present, it
becomes a base station for the WLAN nodes in its broadcast
range. WLAN nodes transmit digital data using Frequency
Modulation (FM) radio signals. WLAN devices generate a
carrier wave and modulate this signal using various
techniques. In this way, digital data can then be
superimposed onto the carrier signal. The radio signal
carries data to wireless-capable devices within its range.
The antennas of wireless-equipped devices transmit and
receive the signal. The transmission method used by
WLAN devices is called Direct Sequence Spread Spectrum
(DSSS) and operates in a range of the radio spectrum
between 2.4 and 2.5 GHz.
Signal Range
WLAN devices are designed to operate over a radius of 100
meters indoors and 300 meters outdoors. Obstructions such
as walls, ceilings, floors, office equipment, and furniture can
reduce this range. WLAN Access Points act as bridges
between WLAN cells and can extend the total range of a
WLAN. Adding WLAN Access Points to areas of the WLAN
where the signal is inadequate can increase the signal
strength in that area.
In an average American 4-bedroom home, range should not
be a problem.
Network Topology
The IEEE 802.11 standard supports three basic topologies
for WLANs − the Independent Basic Service Set (IBSS), the
Basic Service Set (BSS), and the Extended Service Set
(ESS). WLAN components can be used to extend, enhance
or entirely replace existing Ethernet infrastructure. The
Wireless LAN USB Card can accommodate any of these
WLAN topologies.
IBSS
An Independent Basic Service Set or Ad Hoc network
consists of two or more wireless stations that communicate
directly, peer-to-peer, without the services of a wireless
access point. An example of an Ad Hoc or IBSS network
would be a group of wireless-equipped laptop computers at
a trade show set up to share information. In this
arrangement, one of the WLAN units is elected to act as a
controller or base station, similar to the function of a
wireless access point except there is no connection to a
wired Ethernet LAN. Ad Hoc networks are very easy to set
up and require minimal involvement by network
administrators or IT personnel.
BSS
In a Basic Service Set network, a wireless access point
performs multiple tasks − it is a base station and a network
access controller for the wireless stations in the WLAN.
The access point can also provide a connection to a wired
Ethernet LAN for the BSS member stations. An example of
a BSS might be a business meeting conducted in a room
with only a single Ethernet port available. Each
participant has a wireless laptop computer and requires
simultaneous access to a data server on the Ethernet LAN.
A wireless access point provides the connection to the
Ethernet LAN and acts as the network control station for
the BSS network members.
In a BSS network, the wireless access point performs
functions similar to an Ethernet switch. The access point
controls network access and maintains a dynamically
updated list of all the members of the BSS. Wireless
stations in the BSS are identified by their MAC Addresses.
ESS
An Extended Service Set is a series of two or more basic
service sets (BSSs) networked on an Ethernet LAN. Each
access point provides connections to the Ethernet LAN for
their respective BSS members.
Each BSS member is identified by a unique number, the
BSSID (actually the MAC address of the access point).
Wireless stations (such as a laptop computer with a
Wireless LAN USB Card installed) on an ESS network
automatically select the access point or BSS that can serve
them best (has the best signal). If no access point can be
found, the device will scan for a usable access point.
An ESS network can be set up so that wireless stations can
roam anywhere within the range of the access points and
still maintain links to both the WLAN and the Ethernet
LAN. In this case, each station shares a common ESS. The
ESS network is identified by an ESSID that is known and
used by all of the stations in the ESS network.
Wireless access points can also be used to segment a
wireless network. Under such circumstances, more than
one ESS might be used. Two or more separate ESSs can
occupy the same physical space. Each station on a WLAN
can use only one ESS − and thus only one ESSID.
Wireless LAN USB Card Operating
Modes
The Wireless LAN Monitor Utility is installed at the same
time as the WLAN USB Windows driver. Use the Wireless
LAN Monitor Utility to select the operational mode for, and
to generally monitor and configure, the Wireless LAN USB
Card.
The Wireless LAN USB Card supports the following
operational modes:
• In Infrastructure (ESS or 802.11 Station) mode, the
adapter connects to an access point (AP). In ESS mode,
the adapter can roam freely between access point cells
in the network or transmit and receive across subnets.
MUs appear as network nodes to other devices in the
network. ESS is the default mode for the adapter.
• Use the Ad Hoc (IBSS) mode to form peer-to-peer
networks without access points. Use 802.11 Ad Hoc to
create networks where needed within established cells.
The MU starting the IBSS network (the first Wireless
LAN USB Card transmitting a beacon) determines the
channel and data rate used for the other adapters in
the IBSS network.
11 Mbps Operation
The Wireless LAN USB Card supports a maximum 11 Mbps
data transfer rate. When the adapter’s Tx Rate is set to
Auto, the adapter automatically shifts to a 5.5, 2 or 1 Mbps
data rate when unable to maintain a high quality
connection at 11 Mbps. When the Wireless LAN USB Card
detects improved signal strength, it shifts to an increased
data rate, up to the maximum 11Mbps.
The following factors can dynamically alter the data rate:
• signal strength between the access point and USB
Card
• the ratio of good transmitted packets to attempted
transmitted packets that fall below a threshold
• the adapter finds a higher transmit rate with another
AP or it encounters an unspecified data rate.
Note: An 11 Mbps data transfer rate should only be
anticipated in coverage areas where the Scan tool
(part of the Wireless LAN Monitor Utility) has been
used to determine the strength and quality of the
signal between the adapter and an access point.
Physical obstructions and numerous devices
operating in close proximity to one another negatively
impact the ability to maintain an 11 Mbps access
point association.
Wireless LAN USB Card LED
Descriptions
The Wireless LAN USB Card’s LED illuminates during
connection or data transfer to indicate that the adapter is
functioning and is connected to an Access Point
(Infrastructure mode), or a Peer (Ad hoc mode).
The Wireless LAN USB Card has an additional LED that
flashes when activity is detected on the wireless link.
2
Hardware Installation
The physical installation for the Wireless LAN USB Card
amounts to simply plugging the unit’s USB cable into an
available USB port on a USB enabled computer. The
Wireless LAN USB Card should then be located such that
the minimum number of obstructions such as walls, floors,
ceilings, and office equipment are between it and the
nearest access point.
Preparation
Before beginning the installation, verify the hardware
package contains the Wireless LAN USB Card. Keep the
serial number in a safe place. The Support Center uses this
information to reference warranty and service contract
information.
Note: Verify the model indicated on the adapter and
packaging before use. Contact the Support Center if
an item is missing or not functioning.
Installing the Wireless LAN USB Card
The Wireless LAN USB Card installation requires:
• a computer with an available USB port.
• a CDROM drive or internet access.
• an available interrupt (IRQ).
• an available I/O port address.
Avoid exposing the Wireless LAN USB Card liquids or
abrasive materials.
3
Installing and
Configuring
Installing the WLAN Driver in Windows
98
The Wireless LAN USB Card Windows driver ships with
the Wireless LAN Monitor Utility. The utility is installed at
the same time as the Windows USB driver.
Install the Wireless LAN USB driver from the Wireless
LAN USB Card Installation CD and download the driver
and Wireless LAN Monitor Utility. Once downloaded,
extract the files to the computer hard drive.
Before installing the Wireless LAN USB Card Windows
driver:
• Verify the Wireless LAN USB Card is physically
installed in your computer.
• Obtain the Wireless LAN USB Card Installation CD.
To install the Wireless LAN USB Card driver in Windows
98:
1. Insert the adapter’s USB cable into an available USB
port on the computer.
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