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passphrase because the keys are randomly generated.
No predictable passphrases or long sequences of
hexadecimal to enter Information and network credentials
are securely exchanged over the air using the extensible
authentication protocol (EAP), one of the authentication
protocols used in WPA2.
WPS has been integrated and supported in Windows
Vista (currently, Windows Vista only work in registrar
mode).
Disadvantages of WPS
It does not support Ad-Hoc mode or network where
wireless devices are communicated directly to each other
without an access point. All of the Wi-Fi devices on the
network must be WPS certified or WPS-compatible,
otherwise you are not able to take advantage of the ease
of securing the network.
Difficult to add a non-WPS client device to the network
because of the long sequences of hexadecimal characters
generated by the WPS technology. This technology is
fairly new, so not every vendor supports the WPS
technology.
4.5.2.4
Wireless Client requirements
Radio Transmission
Wireless LAN or WLAN devices use electromagnetic waves
within a broad, unlicensed range of the radio spectrum to
transmit and receive radio signals. When a wireless access
point is present, it becomes a base station for the WLAN nodes
in its broadcast range. WLAN nodes transmit digital data using
frequency modulation (FM) radio signals. WLAN devices
generate a carrier wave and modulate this signal using various
techniques. Digital data is superimposed onto the carrier signal.
This radio signal carries data to WLAN devices within range of
the transmitting device. The antennae of WLAN devices listen
for and receive the signal. The signal is demodulated and the
