ZyXEL g-2000 plusv2 Guia Do Utilizador

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ZyXEL G-2000 Plus v2 User’s Guide
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A large Fragmentation Threshold is recommended for networks not prone to interference 
while you should set a smaller threshold for busy networks or networks that are prone to 
interference.
If the Fragmentation Threshold value is smaller than the RTS/CTS value (see previous) you 
set, then the RTS (Request To Send)/CTS (Clear to Send) handshake will never occur as data 
frames will be fragmented before they reach RTS/CTS size. 
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. 
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.