User's Manual

C1_Configuration_Manual_-_fm_1.0.0.1.doc
Commercially Confidential
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antenna gain The measure of an antenna assembly performance relative to a theoretical
antenna, called an isotropic radiator (radiator is another term for antenna). Certain antenna
designs feature higher performance relative to vectors or frequencies.
AP Access Point: A hardware unit that acts as a communication hub by linking wireless
mobile 802.11 stations such as PCs to a wired backbone network. A Trapeze Networks
Mobility System has Mobility Point APs.
ASCII American Standard Code for Information Interchange: An 8-bit code for representing
characters, consisting of 7 data bits plus 1 parity bit.
association The relationship established between mobile (wireless) stations and a wireless AP
(AP) in which the stations receive services from the AP.
bandwidth The gap between the highest and lowest frequencies employed by network signals.
More commonly, it refers to the rated throughput capacity of a network protocol or medium.
The frequency range necessary to convey a signal measured in units of hertz (Hz).
broadcast A data frame or packet that is transmitted to every node on the local network
segment (as defined by the broadcast domain). Broadcasts are known by their broadcast
address, which is a destination network and host address with all the bits turned on.
channel Communication path wide enough to permit a single RF transmission. Multiple
channels can be multiplexed over a single cable in certain environments.
dB decibels: Unit for measuring relative power ratios in terms of gain or loss. Units are
expressed in terms of the logarithm to base 10 of a ratio and typically are expressed in watts.
dB is not an absolute value, rather it is the measure of power lost or gained between two devices.
Because antennas and other RF devices/systems commonly have power gains or losses on the
orders of magnitude or even orders of four orders of magnitude, dB is a more easily used
expression.
dBd decibels over Dipole: A relative gain measurement with respect to a half wave dipole (0
dBd = 2.14 dBi) using a standard dipole antenna as a reference.
dBi dBi referenced to an isotropic antenna, which theoretically is perfect in terms of
symmetric patterns of radiation. Real world antennas do not perform with even nominal
amounts of symmetry, but this effect generally is used to the advantage of the system designer.
dBm decibels per Milliwatt: 0 dBm is defined as 1 mw at 1 kHz of frequency at 600 ohms of
impedance.
DHCP Dynamic Host Configuration Protocol: Provides a mechanism for allocating IP
addresses dynamically so that addresses can be reused when hosts no longer need them.
DNS Domain Name Server: System used on the Internet for translating names of network
nodes into addresses.
DSSS Direct Sequence Spread Spectrum: One of two types of spread spectrum radio
technology used in wireless LAN (WLAN) transmissions. To increase a data signal's
resistance to interference, the signal at the sending station is combined with a higher-rate bit
sequence that spreads the user data in frequency by a factor equal to the spreading ratio.