Cisco Systems WRT54GP2 manual What is ISM band?, What is Spread Spectrum?

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Wireless-G Broadband Router with 2 Phone Ports

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).

Appendix A: Troubleshooting

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Frequently Asked Questions

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Contents Wireless- G Word definition How to Use this GuideCopyright and Trademarks Table of Contents Wireless-G Broadband Router with 2 Phone Ports Wireless Network Access Wireless Security WPAWireless Security Wireless Security WEP32 Administration Tab Log Welcome IntroductionWhat’s in this Guide? Introduction What’s in this Guide? Wireless-G Broadband Router with 2 Phone Ports Network Topology Planning Your Wireless NetworkAd-Hoc versus Infrastructure Mode Ssid your wireless network’s nameNetwork Layout Phone2 Back PanelFront Panel Getting to Know the Router Front Panel Wireless-G Broadband Router with 2 Phone Ports Overview Connecting the RouterConnect a PC Connection InstructionsConfiguring the Router Security SetupWireless Applications & Gaming AdministrationVoice Status How to Access the Web-based UtilityObtain an IP automatically Setup Tab Basic SetupInternet Setup Internet Connection TypePPPoE Static IPPPPoE RAS for SingTelPptp Heart Beat Signal Heart Beat SignalPacket a unit of data sent over a network Network SetupOptional Settings Router IPNetwork Address Server Settings Dhcp Time Setting Setup Tab DdnsTZO.com DynDNS.orgMAC Clone Setup Tab MAC Address Clone12 Setup Tab Advanced Routing Setup Tab Advanced Routing13 Routing Table Entry List Wireless Tab Basic Wireless Settings 15 Wireless Tab Wireless Security WPA Pre-Shared Key Wireless Tab Wireless Security16 Wireless Tab Wireless Security WPA Radius 18 Wireless Tab Wireless Network Access Wireless Tab Wireless Network Access20 Advanced Wireless Settings Wireless Tab Advanced Wireless SettingsWireless-G Broadband Router with 2 Phone Ports Filter MAC Address Security Tab FilterFilter IP Address Range Filter Port RangeInternet requests Block WAN RequestsVPN Passthrough Security Tab VPN PassthroughPort Range Voice TabApplications & Gaming Tab Port Range Forwarding Port Range Forwarding26 Applications & Gaming Tab Port Triggering Forwarded Range Applications & Gaming Tab UPnP ForwardingUPnP Forwarding Wireless-G Broadband Router with 2 Phone Ports Wireless-G Broadband Router with 2 Phone Ports DMZ Applications & Gaming Tab DMZApplication-based QoS Applications & Gaming Tab QoSSpecific Port# fields Port-based QoSVoice QoS Remote Router Access Administration Tab ManagementRouter Password Local Router AccessUPnP Backup and RestoreLog Administration Tab LogFirmware with a newer version Administration Tab Factory DefaultsAdministration Tab Firmware Upgrade Runs a networking deviceLine2 Status Status Tab VoiceInformation Line1 Status38 Status Tab Router Status Tab RouterLocal Network Status Tab Local NetworkStatus Tab Wireless Common Problems and Solutions Appendix a TroubleshootingNeed to set a static IP address on a PC For Windows 98 and MillenniumFor Windows XP For WindowsWant to test my Internet connection For Windows XP Configuring the Router for details Am not able to access the Router’s Web-based Utility Setup Need to set up a server behind my Router TCP Application Start and End Protocol IP Address EnabledCan’t get the Internet game, server, or application to work Wireless-G Broadband Router with 2 Phone Ports For Netscape 4.7 or higher To start over, I need to set the Router to factory defaultMy DSL service’s PPPoE is always disconnecting For Microsoft Internet Explorer 5.0 or higherWireless-G Broadband Router with 2 Phone Ports Need to use port triggering Can I make calls while I’m browsing the Internet? Frequently Asked QuestionsHow do I make a phone call? Can I make calls if my Internet connection is down?Does the Router support IPX or AppleTalk? Where is the Router installed on the network?Is IPSec Passthrough supported by the Router? How can I block corrupted FTP downloads? Wireless-G Broadband Router with 2 Phone Ports Will the Router function in a Macintosh environment? If all else fails in the installation, what can I do?What is DMZ Hosting? How can I check whether I have static or Dhcp IP addresses? Is the Router cross-platform compatible?How many ports can be simultaneously forwarded? Which modems are compatible with the Router?What Ieee 802.11b features are supported? What is the Ieee 802.11b standard?What is the Ieee 802.11g standard? What is roaming? What is ad-hoc mode?What is infrastructure mode? What is Spread Spectrum? What is ISM band?What is a MAC Address? What is DSSS? What is FHSS? And what are their differences?What is WEP? What is WPA?Have excellent signal strength, but I cannot see my network How do I resolve issues with signal loss?Wireless-G Broadband Router with 2 Phone Ports Security Precautions Appendix B Wireless SecuritySecurity Threats Facing Wireless Networks Wireless-G Broadband Router with 2 Phone Ports Wireless-G Broadband Router with 2 Phone Ports Windows 98 or Me Instructions Figure C-1 IP Configuration ScreenFor the Router’s Web-based Utility Windows 2000 or XP InstructionsNetwork Neighborhood/My Network Places Appendix D Windows HelpShared Resources Appendix D Windows Help Appendix E Glossary Appendix E Glossary Wireless-G Broadband Router with 2 Phone Ports Wireless-G Broadband Router with 2 Phone Ports Wireless-G Broadband Router with 2 Phone Ports Wireless-G Broadband Router with 2 Phone Ports Wireless-G Broadband Router with 2 Phone Ports Wireless-G Broadband Router with 2 Phone Ports UPnP able/cert Certified Appendix F SpecificationsModel Voice ProtocolStorage Humidity Dimensions 32 x 1.89 x H x DWarranty Year Limited Limited Warranty Appendix G Warranty InformationAppendix G Warranty Information FCC Statement Appendix H Regulatory InformationSafety Notices Appendix I Contact Information Appendix I Contact Information