User guide

152 Appendix B: Glossary
AirMagnet Laptop Analyzer User Guide
Crash
Any critical failure in a computer, network device, or software application that runs on such
devices. When a crash occurs, a computer may freeze or hang indefinitely. A crash could
occur without warning. The user may have to power down and then restart the computer or
network device in order to recover from a crash.
CRC (Cyclical Redundancy Check)
An error-checking technique used to ensure the accuracy of data transmitted over the
network. Each transmitted message is broken down into predetermined lengths which are
then divided by a fixed divisor. The remainder of the calculation is appended onto and sent with
the message.
Upon receiving the message, the receiving station recalculates the remainder. An
error is detected when it does not match the transmitted remainder.
Data Rate
Refers to the speed (in Mbps) at which data are transmitted over a channel.
dBm (Decibels below 1 Milliwatt)
Decibels relative to 1mw.
Driver
Also called device driver or software driver, is a computer program specifically written for the
wireless network adapter to enable it to interact with higher-level computer programs (e.g., an
operating system, applications, etc.).
Encrypted
A variable that may show up in the Security column in the WiFi Device graph. It means that
the application has determined that packets transmitted by a certain device are encrypted
even though it cannot determine the specific security mechanism that is being used.
Encryption
The reversible transformation of data from the original to a difficult-to-interpret format (the
encrypted) as a way to protect their confidentiality, integrity and sometimes authenticity. It
involves the use of an encryption algorithm and one or more encryption keys.
FCC (Federal Communications Commission)
A United States federal government agency that regulates communications in the country.
FFT Graph
The FFT (Fast Fourier Transform) graph displays the current, average, and maximum power
readings in dBm in the selected spectrum bands or channels.
First Frame Time
The time when the first frame was detected being transmitted from a device in the wireless
environment.
Frame
In communications, a fixed block of data transmitted as a single entity over the network.
IEEE (Institute of Electrical and Electronic Engineers)