Linksys WPC300N manual What is ISM band?, What is Spread Spectrum?, What is WEP?

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Wireless-N Notebook Adapter

simultaneously requires a dynamic RF networking technology that links access points and nodes. In such a system, the user’s end node undertakes a search for the best possible access to the system. First, it evaluates such factors as signal strength and quality, as well as the message load currently being carried by each access point and the distance of each access point to the wired backbone. Based on that information, the node next selects the right access point and registers its address. Communications between end node and host computer can then be transmitted up and down the backbone.

As the user moves on, the end node’s RF transmitter regularly checks the system to determine whether it is in touch with the original access point or whether it should seek a new one. When a node no longer receives acknowledgment from its original access point, it undertakes a new search. Upon finding a new access point, it then re-registers, and the communication process continues.

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? 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 noise and is rejected (ignored) by most narrowband receivers.

What is WEP?

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

Appendix A: Troubleshooting

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Frequently Asked Questions

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Contents GHz How to Use this User Guide Copyright and TrademarksWord definition Table of Contents Wireless-N Notebook Adapter Setup Wizard’s Welcome Screen Front Panel11 WEP Key Needed for Connection Introduction WelcomeWhat’s in this User Guide? Adapter a device that adds network functionality to your PCIntroduction What’s in this User Guide? Planning your Wireless Network Network TopologyRoaming Topology the physical layout of a networkNetwork Layout Getting to Know the Wireless-N Notebook Adapter LED IndicatorsSetting up and Connecting the Wireless-N Notebook Adapter Starting the SetupConnecting the Adapter Setting up the AdapterWPA Personal Needed for Connection WPA2 Personal Needed for Connection Advanced Setup Available Wireless NetworkWEP WPA Personal WPA2 PersonalRadius 18 Confirm New Settings Using the Wireless Network Monitor Accessing the Wireless Network MonitorWireless Network Status screen Link InformationWireless Network Status Wireless Network Statistics More Information Network StatisticsConnect Site InformationProfiles Profile InformationCreate a New Profile 10 Creating a Profile12 WPA Personal Needed for Connection 15 Available Wireless Networks 17 Wireless Mode 19 Wireless Security WEP 20 Wireless Security WPA Personal 22 Wireless Security Radius EAP-TLS 24 Confirm New Settings Appendix a Troubleshooting Common Problems and SolutionsFrequently Asked Questions Wireless-N Notebook Adapter does not work properlyWhat is the Ieee 802.11g standard? What 802.11b features are supported?What Ieee 802.11g features are supported? What is ad-hoc mode?What is ISM band? What is Spread Spectrum?What is DSSS? What is FHSS? And what are their differences? What is WEP?What is WPA? What is RADIUS?Appendix B Windows XP Wireless Zero Configuration Windows XP Wireless Zero ConfigurationFigure B-4 Available Wireless Network Figure B-6 Network Connection Wireless Security Appendix C Wireless Security Security PrecautionsSecurity Threats Facing Wireless Networks Appendix C Wireless Security Wireless-N Notebook Adapter Appendix D Windows Help Shared ResourcesNetwork Neighborhood/My Network Places Appendix E Glossary Wireless-N Notebook Adapter Wireless-N Notebook Adapter Wireless-N Notebook Adapter Wireless-N Notebook Adapter Appendix F Specifications Channels most of Europe and AsiaOperating Humidity Storage HumidityAppendix G Warranty Information Appendix H Regulatory Information FCC StatementWireless-N Notebook Adapter Wireless-N Notebook Adapter Applicable Power Levels in France Open the Wireless Network Connection window Wireless-N Notebook Adapter Wireless-N Notebook Adapter Wireless-N Notebook Adapter Wireless-N Notebook Adapter Wireless-N Notebook Adapter Wireless-N Notebook Adapter Appendix I Contact Information Europe Mail AddressOutside of Europe Mail Address
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