Справочник Пользователя для ZyXEL Communications ZyXEL G-1000 v2
ZyXEL G-1000 v2 User’s Guide
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IEEE 802.11
The 1997 completion of the IEEE 802.11 standard for wireless LANs (WLANs) was a first
important step in the evolutionary development of wireless networking technologies. The
standard was developed to maximize interoperability between differing brands of wireless
LANs as well as to introduce a variety of performance improvements and benefits.
important step in the evolutionary development of wireless networking technologies. The
standard was developed to maximize interoperability between differing brands of wireless
LANs as well as to introduce a variety of performance improvements and benefits.
The IEEE 802.11 specifies three different transmission methods for the PHY, the layer
responsible for transferring data between nodes. Two of the methods use spread spectrum RF
signals, Direct Sequence Spread Spectrum (DSSS) and Frequency-Hopping Spread Spectrum
(FHSS), in the 2.4 to 2.4825 GHz unlicensed ISM (Industrial, Scientific and Medical) band.
The third method is infrared technology, using very high frequencies, just below visible light
in the electromagnetic spectrum to carry data.
responsible for transferring data between nodes. Two of the methods use spread spectrum RF
signals, Direct Sequence Spread Spectrum (DSSS) and Frequency-Hopping Spread Spectrum
(FHSS), in the 2.4 to 2.4825 GHz unlicensed ISM (Industrial, Scientific and Medical) band.
The third method is infrared technology, using very high frequencies, just below visible light
in the electromagnetic spectrum to carry data.