Linksys WMP55AG manual Instant Wireless Series, Dual-Band Wireless A+G PCI Adapter

Instant Wireless® Series

802.11a standard states a maximum data transfer rate of 54Mbps and an oper- ating frequency of 5GHz.

What is the IEEE 802.11b standard?

It is one of the IEEE standards for wireless networks. The 802.11b standard allows wireless networking hardware from different manufacturers to commu- nicate, provided that the hardware complies with the 802.11b standard. The 802.11b standard states a maximum data transfer rate of 11Mbps and an oper- ating frequency of 2.4GHz.

What IEEE 802.11a features are supported?

The product supports the following IEEE 802.11a functions:

•OFDM protocol

•Multi-Channel Roaming

•Automatic Rate Selection

•RTS/CTS feature

•Fragmentation

What IEEE 802.11b features are supported?

The product supports the following IEEE 802.11b functions:

•CSMA/CA plus Acknowledge protocol

•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 com- puters 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.

Dual-Band Wireless A+G PCI Adapter

What is Spread Spectrum?

Spread Spectrum technology is a wideband radio frequency technique devel- oped by the military for use in reliable, secure, mission-critical communica- tions 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? What is FHSS? And what are their differences? Frequency-HoppingSpread-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-SequenceSpread-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 trans- mission, 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 nar- rowband receivers.

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 technology, it has the inherent security fea- ture of scrambling. On the software side, WLAN offers the encryption function (WEP) to enhance security and access control.

Can Instant Wireless products support 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 network operating systems to support printer or file sharing.

What is WEP?

WEP is Wired Equivalent Privacy, a data privacy mechanism based on a 40/64 bit shared key algorithm, as described in the IEEE 802.11 standard.

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