User's Manual

Glossary
ISM Bands: A series of frequency bands, set aside by the FCC for Industrial, Scientific and Medical
applications. Users of these bands operate equipment on a shared basis, meaning that they must expect, and
accept interference from other legal users. Products manufactured for ISM Band use must be approved by the
FCC, but the user does not have to be licensed. In addition to WLAN, ISM bands support cordless phones,
microwave ovens, baby monitors, toys, ham radio transceivers, and other wireless services.
K
Kerberos: An authentication system enabling protected communication over an open network using a unique
key called a ticket.
M
Media Access Control (MAC) Address: A hardwired address applied at the factory. It uniquely identifies
network hardware, such as a wireless PC Card, on a LAN or WAN.
Microcell: A bounded physical space in which a number of wireless devices can communicate. Because it is
possible to have overlapping cells as well as isolated cells, the boundaries of the cell are established by some
rule or convention.
Microwave: Technically, the term describes any frequency above 1.0 GHz.
Multipath: The signal variation caused when radio signals take multiple paths from transmitter to receiver.
O
Orthogonal Frequency Division Multiplexing (OFDM): A modulation technique for transmitting large
amounts of digital data over radio waves. 802.11a and 802.11g use OFDM.
P
Personal Area Network (PAN): A personal area network, or PAN, is a networking scheme that enables
computing devices such as PCs, laptop computers, handheld personal computers, printers and personal digital
assistants (PDAs) to communicate with each other over short distances either with or without wires.
Preamble: A preliminary signal transmitted over a WLAN to control signal detection and clock synchronization.
R
Radio Frequency (RF) Terms (GHz, MHz, Hz): The international unit for measuring frequency is Hertz (Hz),
which is equivalent to the older unit of cycles per second. One Mega-Hertz (MHz) is one million Hertz. One
Giga-Hertz (GHz) is one billion Hertz. For reference: the standard US electrical power frequency is 60 Hz, the
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