Linksys WRT54G3G-VN What is DSSS? What is FHSS? And what are their differences?, What is WEP?

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Wireless-G Router for Mobile Broadband

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 64-bit or 128-bit shared key algorithm, as described in the IEEE 802.11 standard.

What is a MAC Address?

The Media Access Control (MAC) address is a unique number assigned by the manufacturer to any Ethernet networking device, such as a network adapter, that allows the network to identify it at the hardware level. For all practical purposes, this number is usually permanent. Unlike IP addresses, which can change every time a computer logs onto the network, the MAC address of a device stays the same, making it a valuable identifier for the network.

How do I reset the Router?

Press the Reset button on the back panel for about five seconds. This will reset the Router to its default settings.

How do I resolve issues with signal loss?

There is no way to know the exact range of your wireless network without testing. Every obstacle placed between the Router and a wireless PC will create signal loss. Lead glass, metal, concrete floors, water and walls will inhibit the signal and reduce range. Start with the Router and your wireless PC in the same room and move it away in small increments to determine the maximum range in your environment.

You may also try using different channels, as this may eliminate interference affecting only one channel. I have excellent signal strength, but I cannot see my network.

Wireless security is probably enabled on the Router, but not on your wireless adapter (or vice versa). Verify that the same wireless security method and passphrase/keys are being used on all devices of your wireless network.

Appendix A: Troubleshooting

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Frequently Asked Questions

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Contents 802 GHz .11g Wireless- G Word definition How to Use This User GuideCopyright and Trademarks Table of Contents Appendix a Troubleshooting Appendix B Wireless SecurityCommon Problems and Solutions Frequently Asked Questions Appendix C Upgrading Firmware Appendix D Windows HelpList of Figures Router’s Ports17 Setup Tab Advanced Routing Router 51 Status Tab Wireless Introduction WelcomeWhat’s in this User Guide? Wireless-G Router for Mobile Broadband Planning Your Wireless Network Ad-Hoc versus Infrastructure ModeSsid service set identifier your wireless network’s name Network TopologyPlanning Your Wireless Network Network Layout Getting to Know the Wireless-G Router for Mobile Broadband Router’s PortsRouter’s LEDs Router’s LEDs are located on the Router’s other side panelRouter’s Data Card Slot Connecting the Wireless-G Router for Mobile Broadband OverviewConnect Your Computer Hardware Installation for Connection to Your Broadband Modem Connect the Power Hardware Installation for Connection to Another Router Diagram for Connection to Another RouterConnect Your Computer Placement Options Stand OptionWall-Mount Option 11 Measurement between Wall-Mount SlotsConfiguring the Wireless-G Router for Mobile Broadband Password ScreenSetup Tab Basic Setup Mobile Network SetupInternet Setup StatusStatic IP Connection Type Optional Settings L2TP Connection TypeRouter IP Network SetupNetwork Address Server Settings Dhcp Time Setting 11 Time SettingSetup Tab Mobile Network Mobile Network Connection ModeMobile Network Status Data Card StatusTZO.com Setup Tab DdnsDynDNS.org Setup Tab MAC Address Clone MAC CloneSetup Tab Advanced Routing Advanced RoutingDynamic Routing Static RoutingWireless Tab Basic Wireless Settings Wireless NetworkWireless Tab Wireless Security Wireless SecurityAES 25 Wireless Tab Wireless Security Radius Wireless Tab Wireless MAC Filter Wireless MAC FilterWireless Tab Advanced Wireless Settings Advanced WirelessWireless-G Router for Mobile Broadband Block WAN Requests Security Tab FirewallFirewall Access Restrictions Tab Internet Access Internet AccessTo create an Internet Access policy Security Tab VPN Passthrough33 Internet Policy Summary Applications and Gaming Tab Port Range Forward Port Range ForwardApplications & Gaming Tab Port Triggering Port TriggeringTriggered Range Forwarded RangeWired QoS Applications and Gaming Tab DMZApplications and Gaming Tab QoS Device PriorityApplication Priority Wireless QoSEthernet Port Priority UPnP Administration Tab ManagementRouter Password Administration Tab Log LogTraceroute Test Administration Tab DiagnosticsPing Test Administration Tab Config Management Administration Tab Factory DefaultsAdministration Tab Firmware Upgrade Status Tab Mobile Network 48 Status Tab Mobile NetworkInternet Status Tab RouterRouter Information Status Tab Local Network Local NetworkStatus Tab Wireless WirelessNeed to set a static IP address on a PC Appendix a TroubleshootingCommon Problems and Solutions Wireless-G Router for Mobile Broadband Wireless-G Router for Mobile Broadband Application Start and End Protocol IP Address Enabled TCPCan’t get the Internet game, server, or application to work My DSL service’s PPPoE is always disconnecting To start over, I need to set the Router to factory defaultNeed to upgrade the firmware Power LED keeps flashing Frequently Asked Questions Where is the Router installed on the network?Is IPSec Pass-Through supported by the Router? Does the Router support IPX or AppleTalk?How can I avoid corrupted FTP downloads? If all else fails in the installation, what can I do?How will I be notified of new Router firmware upgrades? What is DMZ Hosting? What are the advanced features of the Router?Will the Router function in a Macintosh environment? Is the Router cross-platform compatible?What is the Ieee 802.11g standard? What is the Ieee 802.11b standard?What Ieee 802.11g features are supported? What Ieee 802.11b features are supported?What is infrastructure mode? What is roaming?What is ISM band? What is Spread Spectrum?What is DSSS? What is FHSS? And what are their differences? What is WEP?What is a MAC Address? How do I reset the Router?What do the indicator LEDs signify on the Router? How do I connect to the mobile network?How do I know which mobile network I am using? Whom should I call if there is a question or problem?Security Threats Facing Wireless Networks Appendix B Wireless SecuritySecurity Precautions Appendix B Wireless Security Wireless-G Router for Mobile Broadband Figure C-1 Upgrade Firmware Appendix C Upgrading FirmwareNetwork Neighborhood/My Network Places Appendix D Windows HelpShared Resources Windows 2000 or XP Instructions For the Router’s Web-based UtilityFigure E-4 MAC Address Filter List Appendix F Glossary Wireless-G Router for Mobile Broadband Wireless-G Router for Mobile Broadband Wireless-G Router for Mobile Broadband Wireless-G Router for Mobile Broadband Appendix G Specifications FCC, IC-03, CE, Wi-Fi 802.11b, 802.11g, WPA Appendix H Warranty Information Appendix I Regulatory Information Wireless-G Router for Mobile Broadband Wireless-G Router for Mobile Broadband Wireless-G Router for Mobile Broadband Wireless-G Router for Mobile Broadband Wireless-G Router for Mobile Broadband Wireless-G Router for Mobile Broadband