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FAQ
• CSMA/CA plus Acknowledge Protocol
• Multi-Channel Roaming
• Automatic Rate Selection
• RTS/CTS Feature
• Fragmentation
• Power Management
What is Ad Hoc?
An Ad Hoc integrated wireless LAN is a group of computers, each with a wireless
LAN card. Connected as an independent wireless LAN, it’s applicable at a
departmental scale for a branch or SOHO operation.
What is Infrastructure?
An integrated wireless and wired LAN is called an Infrastructure configuration. It’s
applicable to enterprise scale for wireless access to a central database or wireless
application for mobile workers.
What is BSS ID?
A specific Ad Hoc LAN is called a basic service set (BSS). Computers in a BSS
must be configured with the same BSS ID.
What is WEP?
WEP is Wired Equivalent Privacy, a data privacy mechanism based on a 40-bit
shared-key algorithm, as described in the IEEE 802 .11 standard.
Can information be intercepted while transmitting over the air?
WLAN features two-fold protection in security. On the hardware side, as with
Direct Sequence Spread Spectrum technology, it has the inherent security feature
of scrambling. On the software side, WLAN series offer the encryption function
(WEP) to enhance security and Access Control. Users can set it up depending
upon their needs.
What is DSSS? What is FHSS? And what are their differences?
Frequency-hopping spread-spectrum (FHSS) uses a narrowband carrier that
changes frequency in a pattern that is known to both transmitter and receiver.
Properly synchronized, the net effect is to maintain a single logical channel. To an
unintended receiver, FHSS appears to be short-duration impulse noise. Direct-
sequence spread-spectrum (DSSS) generates a redundant bit pattern for each bit
to be transmitted. This bit pattern is called a chip (or chipping code). The longer the
chip, the greater the probability that the original data can be recovered. Even if one
or more bits in the chip are damaged during transmission, statistical techniques
embedded in the radio can recover the original data without the need for
retransmission. To an unintended receiver, DSSS appears as low power wideband
