CompUSA 333626, Инструкция по установке и эксплуатации

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8. What is TKIP?
TKIP is a quick-fix method to quickly overcome the inherent weaknesses in WEP security, especially
the reuse of encryption keys. TKIP is involved in the IEEE 802.11i WLAN security standard.
9. What is AES?
AES (Advanced Encryption Standard), a chip-based security, has been developed to ensure the highest
degree of security and authenticity for digital information, wherever and however communicated or
stored, while making more efficient use of hardware and/or software than previous encryption standards.
It is also included in IEEE 802.11i standard. Compare with AES, TKIP is a temporary protocol for
replacing WEP security until manufacturers implement AES at the hardware level.
10. Can Wireless products support printer sharing?
Wireless products perform the same function as LAN products. Therefore, Wireless products can work
with Netware
®
, Windows
®
2000, or other LAN operating systems to support printer or file sharing.
11. Would the information be intercepted while transmitting on air?
WLAN features two-fold protection in security. On the hardware side, as with Direct Sequence Spread
Spectrum (DSSS) 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.
12. 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 is, 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.
13. What is Spread Spectrum?
Spread Spectrum technology is a wideband radio frequency technique developed by the military for use
in reliable, secure, mission-critical communication 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).