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3-3 Glossary
1. What is the IEEE 802.11g standard?
802.11g is the new IEEE standard for high-speed wireless LAN communications that provides for up to
54 Mbps data rate in the 2.4 GHz band. 802.11g is quickly becoming the next mainstream wireless LAN
technology for the home, office and public networks.
802.11g defines the use of the same OFDM modulation technique specified in IEEE 802.11a for the 5
GHz frequency band and applies it in the same 2.4 GHz frequency band as IEEE 802.11b. The 802.11g
standard requires backward compatibility with 802.11b.
The standard specifically calls for:
A. A new physical layer for the 802.11 Medium Access Control (MAC) in the 2.4 GHz frequency band,
known as the extended rate PHY (ERP). The ERP adds OFDM as a mandatory new coding scheme
for 6, 12 and 24 Mbps (mandatory speeds), and 18, 36, 48 and 54 Mbps (optional speeds). The ERP
includes the modulation schemes found in 802.11b including CCK for 11 and 5.5 Mbps and Barker
code modulation for 2 and 1 Mbps.
B. A protection mechanism called RTS/CTS that governs how 802.11g devices and 802.11b devices
interoperate.
2. What is the IEEE 802.11b standard?
The IEEE 802.11b Wireless LAN standard subcommittee which formulates the standard for the industry.
The objective is to enable wireless LAN hardware from different manufactures to communicate.
3. What does IEEE 802.11 feature support?
The product supports the following IEEE 802.11 functions:
z
CSMA/CA plus Acknowledge Protocol
z
Multi-Channel Roaming
z
Automatic Rate Selection
z
RTS/CTS Feature
z
Fragmentation
z
Power Management
4. What
is
Ad-hoc?
An Ad-hoc integrated wireless LAN is a group of computers, each has a Wireless LAN card, Connected
as an independent wireless LAN. Ad hoc wireless LAN is applicable at a departmental scale for a branch
or SOHO operation.
5. What is Infrastructure?
An integrated wireless and wireless and wired LAN is called an Infrastructure configuration.
Infrastructure is applicable to enterprise scale for wireless access to central database, or wireless
application for mobile workers.
6. What is BSS ID?
A specific Ad hoc LAN is called a Basic Service Set (BSS). Computers in a BSS must be configured with
the same BSS ID.
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