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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.
