Linksys WET54GS5 manual What is ISM band?

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Wireless-G Ethernet Bridge with 5-Port Switch

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.

Would the information be intercepted while transmitting on air?

Linksys products feature 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, Linksys products offer the encryption function (WEP) to enhance security and access control. Users can set it up depending upon their needs.

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.

Appendix A: Troubleshooting

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Frequently Asked Questions

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Contents Wireless- G How to Use this Guide Copyright and TrademarksTable of Contents Appendix I Contact Information FCC Statement Industry Canada CanadaList of Figures Infrastructure Network10 WPA RADIUS-TTLS Introduction What’s in this Guide? Wireless-G Ethernet Bridge with 5-Port Switch Ad-Hoc versus Infrastructure Mode Planning Your Wireless NetworkNetwork Topology Network Layout Ad-Hoc NetworkBack Panel Front Panel Side Panel Power port is on the side panel. See Figure Connecting the Wireless-G Ethernet Bridge for Setup Wireless-G Ethernet Bridge with 5-Port Switch Setting Up the Wireless-G Ethernet Bridge WelcomePassword Mode Settings Wireless Settings Security Settings 10 Confirmation Wall Mount Placement Option Connecting the Wireless-G Ethernet Bridge for Network UseConnection to a Network Device Overview Using the Wireless-G Ethernet Bridge Web-based UtilityStarting the Web-based Utility Setup LANSite Survey WEP Radius TLS Ttls WPA Radius 10 WPA RADIUS-TTLS 11 WPA Pre-Shared Key 13 Password Tab Advanced Wireless WirelessMAC Address Switch Tab Spanning Tree ProtocolQOS Switch Table 17 Switch Table TabVlan Wireless-G Ethernet Bridge with 5-Port Switch Rmon Statistics 19 Rmon Statistics TabWireless-G Ethernet Bridge with 5-Port Switch Port Mirroring Port Information TableAccess List 21 Access List TabWireless Status LAN SettingsWireless Settings StatisticsSnmp Help 24 Help TabAppendix a Troubleshooting Common Problems and SolutionsFrequently Asked Questions Web-based Utility won’t openWhat is ad-hoc mode? What is ISM band? Security Precautions Appendix B Wireless SecuritySecurity Threats Facing Wireless Networks Appendix B Wireless Security Wireless-G Ethernet Bridge with 5-Port Switch Figure C-1 Firmware Upgrade Appendix C Upgrading FirmwareShared Resources Appendix D Windows HelpNetwork Neighborhood/My Network Places Appendix E Glossary Wireless-G Ethernet Bridge with 5-Port Switch Wireless-G Ethernet Bridge with 5-Port Switch Wireless-G Ethernet Bridge with 5-Port Switch Wireless-G Ethernet Bridge with 5-Port Switch Wireless-G Ethernet Bridge with 5-Port Switch Wireless-G Ethernet Bridge with 5-Port Switch Appendix F Specifications Security FeatureModel StandardsWarranty Year Limited Warranty Operating TempStorage Temp Operating HumidityAppendix G Warranty Information Limited WarrantyAppendix H Regulatory Information FCC StatementIndustry Canada Canada FCC Radiation Exposure StatementAppendix I Contact Information
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