| access point |
A stand-alone wireless hub that allows any computer that has
a wireless network adapter to communicate with another computer and to connect
to the Internet. |
| ad hoc network |
A communication configuration in which every computer has
the same capabilities, and any computer can initiate a communication session.
Also known as a peer-to-peer network or a computer-to-computer network. |
| AES |
Advanced Encryption Standard An additional replacement
for WEP encryption. |
| antenna diversity |
A technique for mitigating the effects of multipath (reflected
signals associated with RF) by placing multiple antennas in two separate
(but adjacent) locations. Also known as spatial diversity. |
| available network |
One of the networks listed under Available networks
on the Wireless Networks tab of the Wireless Configuration
Utility (Windows 2000 environment) or Wireless Network Connection
Properties (Windows XP environment). Any wireless network that is broadcasting
and is within receiving range of the Dell TrueMobile WLAN Card appears on
the list. |
| BSS |
basic service set Two or more nodes (stations) in the
network. A node can be an AP or a client computer. |
| BER |
bit error rate The ratio of errors to the total number
of bits being sent in a data transmission from one location to another. |
| client computer |
The computer that gets its Internet connection by sharing
either the host computer's connection or the access point's connection. |
| CCK |
complimentary code keying The modulation technique
for high and medium transmit rates. |
| CSMA/CA |
carrier sense multiple access with collision avoidance
An IEEE 802.11 protocol that ensures that the number of collisions within
a domain are kept to a minimum. |
| dBm |
A unit of expression of power level in decibels with reference
to a power of 1 milliwatt. |
| DBPSK |
differential binary phase shift keying The modulation
technique used for low transmit rate. |
| DQPSK |
differential quadrature phase shift keying The modulation
technique used for standard transmit rate. |
| DSSS |
direct sequence spread spectrum A spreading technique
in which various data, voice, and/or video signals are transmitted over
a specific set of frequencies in a sequential manner from lowest to highest
frequency, or highest to lowest frequency. |
| DHCP |
Dynamic Host Configuration Protocol A mechanism for
allocating IP addresses dynamically so that addresses can be reused when
hosts no longer need them. |
| file and printer sharing |
A capability that allows a number of people to view, modify,
and print the same file(s) from different computers. |
| fragmentation threshold |
The threshold at which the WLAN card adapter breaks the packet
into multiple frames. This determines the packet size and affects the throughput
of the transmission. |
| GHz |
gigahertz A unit of frequency equal to 1 000 000 000
cycles per second. |
| host computer |
The computer that is directly connected to the Internet via
a modem or network adapter. |
| IBSS |
independent basic service set A BSS that forms a self-contained
network (such as an ad hoc network), and in which there is no access to
an AP. |
| IBSS channel number |
The IBSS channel number on which the network operates. |
| IEEE |
Institute of Electrical and Electronics Engineers, Inc. |
| 802.1x |
A group of wireless local area network (WLAN) standards that
are being developed as part of overall IEEE 802.11 WLAN support. As of March
2003, these incomplete standards included IEEE 802.11e (Quality of Service),
IEEE 802.11f (Access Point Interoperability), IEEE 802.11h (Interference),
and IEEE 802.11i (Security). |
| Internet Protocol (IP) address |
The address of a computer that is attached to a network. Part
of the address designates which network the computer is on, and the other
part represents the host identification. |
| LAN |
local area network A high-speed, low-error data network
covering a relatively small geographic area. |
| m |
meter |
| LEAP |
Light Extensible Authentication Protocol A version
of Extensible Authentication Protocol (EAP). EAP ensures mutual authentication
between a wireless client and a server that resides at the network operations
center. |
| MHz |
megahertz A unit of frequency equal to 1 000 000 cycles
per second. |
| Mbps |
megabits per second Transmission speed of 1 000 000
bits per second. |
| ns |
nanosecond 1 billionth (1/1 000 000 000) of a second. |
| OFDM |
orthogonal frequency division multiplexing A frequency
division modulation technique for transmitting signals by splitting the
radio signal into various frequencies that are then transmitted simultaneously,
rather than sequentially. |
| Power Save mode |
The state in which the radio is periodically powered down
to conserve power. When the notebook is in Power Save mode, receive packets
are stored in the AP until the notebook comes on. |
| PLCP |
physical layer convergence protocol One of the two
sublayers of the physical layer (PHY) that handles Barker and CCK encoding,
modulation techniques such as QPSK, and the DSSS spreading technique. |
| preferred network |
One of the networks that has been configured. Such networks
are listed under Preferred networks on the Wireless Networks
tab of the Wireless Configuration Utility (Windows 2000 environment)
or Wireless Network Connection Properties (Windows XP environment). |
| RF |
radio frequency |
| RTS threshold |
The number of frames in the data packet at or above which
an RTS/CTS (request to send/clear to send) handshake is turned on before
the packet is sent. The default value is 2347. |
| QAM |
quadrature amplitude modulation A modulation technique
that uses variations in signal amplitude and phase to represent data-encoded
symbols as a number of states. |
| SSID |
service set identifier A value that controls access
to a wireless network. The SSID for your wireless network card must match
the SSID for any access point that you want to connect with. If the value
does not match, you are not granted access to the network. You can have
up to three SSIDs. Each SSID can be up to 32 characters long and is case-sensitive. |
| WEP |
Wired Equivalent Privacy A form of data encryption. |
| WPA |
Wi-Fi Protected Access A new standards-based, interoperable
security technology for wireless LAN (subset of IEEE 802.11i draft standard)
that encrypts data sent over radio waves. |
