User's Manual

32 ASUS WLAN Adapter
Chapter 5
Chapter 5 - Glossary
Glossary
Ethernet
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standard. Ethernet is normally a shared media LAN meaning all devices on the
network segment share total bandwidth. Ethernet networks operate at 10Mbps
using CSMA/CD to run over 10-BaseT cables.
Firewall
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A Firewall prevents anyone outside of your network from accessing your computer
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Gateway
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Internet and connects one network to another.
IEEE
The Institute of Electrical and Electronics Engineers. The IEEE sets standards
for networking, including Ethernet LANs. IEEE standards ensure interoperability
between systems of the same type.
IEEE 802.11
IEEE 802.xx is a set of specifications for LANs from the Institute of Electrical
and Electronic Engineers (IEEE). Most wired networks conform to 802.3, the
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three incompatible (non-interoperable) technologies: Frequency Hopping Spread
Spectrum (FHSS), Direct Sequence Spread Spectrum (DSSS), and Infrared.
802.11 specifies a carrier sense media access control and physical layer
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IEEE 802.11a (54Mbits/sec)
Compared with 802.11b:
The 802.11b standard was designed to operate in
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spread-spectrum technology. The 802.11a standard, on the other hand, was
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National Information Infrastructure) band. And unlike 802.11b, the 802.11a standard
departs from the traditional spread-spectrum technology, instead using a frequency
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The 802.11a standard, which supports data rates of up to 54 Mbps, is the Fast
Ethernet analog to 802.11b, which supports data rates of up to 11 Mbps. Like
Ethernet and Fast Ethernet, 802.11b and 802.11a use an identical MAC (Media
Access Control). However, while Fast Ethernet uses the same physical-layer
encoding scheme as Ethernet (only faster), 802.11a uses an entirely different
encoding scheme, called OFDM (orthogonal frequency division multiplexing).