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4-3 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.
