2.4GHz Wireless PCI-E Adapter
RNX-N150PCe User Manual
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Appendix B: Glossary
802.11b -
The 802.11b standard specifies a wireless product networking at 11
Mbps using direct-sequence spread-spectrum (DSSS) technology and operating
in the unlicensed radio spectrum at 2.4GHz, and WEP encryption for security.
802.11b networks are also referred to as Wi-Fi networks.
802.11g-
specification for wireless networking at 54 Mbps using direct-sequence
spread-spectrum (DSSS) technology, using OFDM modulation and operating in
the unlicensed radio spectrum at 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 independent 802.11 wireless LAN. Ad-hoc
wireless computers operate on a peer-to-peer basis, communicating directly with
each other without the use of an access point. Ad-hoc mode is also referred to as
an Independent Basic Service Set (IBSS) or as peer-to-peer mode, and is useful
at a departmental scale or SOHO operation.
DSSS -
(
D
irect-
S
equence
S
pread
S
pectrum)
-
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 during transmission, statistical
techniques embedded in the receiver can recover the original data without the
need of retransmission. To an unintended receiver, DSSS appears as low power
wideband noise and is rejected (ignored) by most narrowband receivers. However,
to an intended receiver (i.e. another wireless LAN endpoint), the DSSS signal is
recognized as the only valid signal, and interference is inherently rejected
(ignored).
FHSS -
(
F
requency
H
opping
S
pread
S
pectrum)
-
FHSS continuously changes
(hops) the carrier frequency of a conventional carrier several times per second
according to a pseudo-random set of channels. Because a fixed frequency is not
used, and only the transmitter and receiver know the hop patterns, interception of
FHSS is extremely difficult.
Infrastructure Network -
An infrastructure network is a group of computers or
other devices, each with a Wireless 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 referred to as a Basic Service
Set (BSS). A set of two or more BSS in a single network is referred to as an
Extended Service Set (ESS). Infrastructure mode is useful at a corporation scale,
or when it is necessary to connect the wired and wireless networks.
Spread Spectrum -
Spread Spectrum technology is a wideband radio frequency
technique developed by the military for use in reliable, secure, mission-critical
communications systems. It is designed to trade off bandwidth efficiency for
reliability, integrity, and security. In other words, more bandwidth is consumed
