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• Multi-Channel Roaming
• Automatic Rate Selection
• RTS/CTS feature
• Fragmentation
• Power Management
What is ad-hoc mode?
When a wireless network is set to ad-hoc mode, the wireless-equipped computers are
configured to communicate directly with each other. The ad-hoc wireless network will not
communicate with any wired network.
What is infrastructure mode?
When a wireless network is set to infrastructure mode, the wireless network is
configured to communicate with a wired network through a wireless access point.
What is ISM band?
The FCC and their counterparts outside of the U.S. have set aside bandwidth for
unlicensed use in the ISM (Industrial, Scientific and Medical) band. Spectrum in the
vicinity of 2.4 GHz, in particular, is being made available worldwide. This presents a truly
revolutionary opportunity to place convenient high-speed wireless capabilities in the
hands of users around the globe.
What is Spread Spectrum?
Spread Spectrum technology is a wideband radio frequency technique developed by the
military for use in reliable, secure, mission-critical communications systems. It is
designed to trade off bandwidth efficiency for reliability, integrity, and security. In other
words, more bandwidth is consumed than in the case of narrowband transmission, but
the trade-off produces a signal that is, in effect, louder and thus easier to detect,
provided that the receiver knows the parameters of the spread-spectrum signal being
broadcast. If a receiver is not tuned to the right frequency, a spread-spectrum signal
looks like background noise. There are two main alternatives,
Direct Sequence Spread Spectrum (DSSS) and Frequency Hopping Spread Spectrum
(FHSS).
What is DSSS?
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 noise and is rejected
(ignored) by most narrowband receivers.
Would the information be intercepted while transmitting on air?
Instant wireless products feature two-fold protection in security. On the hardware side,
as with Direct Sequence Spread Spectrum technology, it generates security feature of
scrambling. On the software side, instant wireless products offer the encryption function
(WEP) to enhance security and access control. Users can set it up depending upon their
needs. Can instant wireless products support file and printer sharing? Instant wireless
products perform the same function as LAN products. Therefore, instant wireless
products can work with NetWare, Windows NT/2000, or other LAN operating systems to
support printer or file sharing.
What is WEP?