aqprox! appPCI300, User Manual

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300Mbps Wireless N PCI Adapter – APPPCI300 User’s Guide English
Appendix B: Glossary
- The 802.11b standard specifies a wireless product networking at 11 Mbps using
pectrum (DSSS) technology and operating in the unlicensed radio
at 2.4GHz, and ecurity. 802.11b networks are also referred to
as Wi-Fi networks.
802.11g - specification for wireless networking at 54 Mbps using direct-sequence
(DSSS the
2.4GHz, and backward compatibility with IEEE 802.11b devices,
and WEP encryption for security.
Ad-hoc Network - An ad-hoc network is a group of computers, each with a Wireless Adapter,
connected as an indepen s computers operate on a
peer-to-peer basis, communicating dir out the use of an access point.
also re as
peer-to-peer mode, and is OHO operation.
DSSS - ( D irect- S equence ) - DSSS generates a redundant bit pattern for all
data transmitted. This bit pattern is called a chip (or chipping code). Even if one or more bits
in the chip are damaged d atistical techniques embedded in the receiver
can recover the original d etransmission. To an unintended receiver,
DSSS appears as low power wi s rejected (ignored) by most narrowband
owever, to an (i.e. another wireless LAN endpoint), the DSSS
signal is recognized as the only valid signal, and interference is inherently rejected (ignored).
- FHSS continuously changes (hops) the
several times per second according to a
m set of c used, and only the
transmitter and receiver know the hop patterns, interception of FHSS is extremely difficult.
work - ces,
Adapter, connected as an 802.11 wireless LAN. In infrastructure mode,
the wireless devices communicate with each other and to a wired network by first going
through an access point. An infrastructure wireless network connected to a wired network is
A set of two or more BSS in a single network is
rvice Set (ESS). Infrastructure mode is useful at a corporation
s neces and wireless networks.
um - Spre quency technique
developed by the military for use in reliable, secure, mission-critical communications systems.
ade of ability, integrity, and security. In other
words, more bandwidth is consumed than in the case of narrowband transmission, but the
a signa asier to detect, provided that the
receiver knows the parameters of the spread-spectrum signal being broadcast. If a receiver is
not tuned to the right frequency, a spread-spectrum signal looks like background noise.
There are two main alternatives, Direct Sequence Spread Spectrum (DSSS) and Frequency
Hopping Spread Spectrum (FHSS).
802.11b
direct-sequence spread-s
spectrum WEP encryption for s
spread-spectrum
unlicensed radio spectrum at
) technology, using OFDM modulation and operating in
dent 802.11 wireless LAN. Ad-hoc wireles
ectly with each other with
ferred to as an Independent Basic Service Set (IBSS) or Ad-hoc mode is
useful at a departmental scale or S
S pread S pectrum
uring transmission, st
ata without the need of r
deband noise and i
receivers. H intended receiver
FHSS - ( F requency H opp
carrier frequency of a
ing S pread S pectrum)
conventional carrier
pseudo-rando hannels. Because a fixed frequency is not
Infrastructure Net An infrastructure network is a group of computers or other devi
each with a Wireless
referred to as a Basic Service Set (BSS).
referred to as an Extended Se
scale, or when it i sary to connect the wired
Spread Spectr ad Spectrum technology is a wideband radio fre
It is designed to tr f bandwidth efficiency for reli
trade off produces l that is, in effect, louder and thus e
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