ZyXEL Communications 320W manual What is Direct-Sequence Spread Spectrum Technology DSSS?

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P320W Support Notes

What is Direct-Sequence Spread Spectrum Technology – (DSSS)?

DSSS spreads its signal continuously over a wide frequency band. DSSS maps the information bearing bit-pattern at the sending station into a higher data rate bit sequence using a "chipping" code. The chipping code (also known as processing gain) introduces redundancy which allows data recovery if certain bit errors occur during transmission. The FCC rules the minimum processing gain should be 10, typical systems use processing gains of 20. IEEE 802.11b specifies the use of DSSS.

What is Frequency-hopping Spread Spectrum Technology – (FHSS)?

FHSS uses a narrowband carrier which hops through a predefined sequence of several frequencies at a specific rate. This avoids problems with fixed channel narrowband noise and simple jamming. Both transmitter and receiver must have their hopping sequences synchronized to create the effect of a single "logical channel". To an unsynchronised receivers an FHSS transmission appears to be short-duration impulse noise. 802.11 may use FHSS or DSSS.

Do I need the same kind of antenna on both sides of a link?

No. Provided the antenna is optimally designed for 2.4GHz or 5GHz operation. WLAN NICs often include an internal antenna which may provide sufficient reception.

Why the 2.4 Ghz Frequency range?

This frequency range has been set aside by the FCC, and is generally labeled the ISM band. A few years ago Apple and several other large corporations requested that the FCC allow the development of wireless networks within this frequency range. What we have today is a protocol and system that allows for unlicensed use of radios within a prescribed power level. The ISM band is populated by Industrial, Scientific and Medical devices that are all low power devices, but can interfere with each other.

What is Server Set ID (SSID)?

SSID is a configurable identification that allows clients to communicate to the appropriate base station. With proper configuration, only clients that are configured with the same SSID can communicate with base stations having the same SSID. SSID from a security point of view acts as a simple single shared password between base stations and clients.

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Contents Prestige 320W P320W Support Notes Ireless FAQ Trouble Shooting Ethernet connection Internet ConnectionTCP/IP Configuration TCP/IP InstallationSetting up the Prestige router P320W Support Notes P320W Support Notes Configure an Internal Server Behind SUA Smtp Service Port NumberUsing the Dynamic DNS Ddns Snmp Overview Network Management Using SnmpP320W Support Notes SNMPv1 Operations Trap GetGetNext SetZyXEL Snmp Implementation Get Community Configure the Prestige for SnmpSet Community Using Prestige traffic redirectTraffic Redirect on LAN port What is UPnP Using Universal Plug n Play UPnPUsing UPnP in ZyXEL devices Go to Management-UPnP, check Enable UPnP service P320W Support Notes Finally, your video conversation is achieved What is Infrastructure mode? Infrastructure ModeP320W Support Notes Configuration Wireless Station to Infrastructure mode P320W Support Notes Double click on the AP you want to associated with MAC Filter Overview Wireless MAC Address FilteringZyXEL MAC Filter Implementation Configure the Wlan MAC FilterIntroduction WEP ConfigurationP320W Support Notes Setting up the Access Point Setting up the Station Key settingsP320W Support Notes P320W Support Notes Ieee 802.1x Introduction IeeeAuthentication Server AuthenticatorSupplicant Authentication Port State and Authentication Control Re-Authentication Eapol Exchange between 802.1x Authenticator and Supplicant P320W Support Notes Using WEB Configuration Using External Radius Authentication Server P320W Support Notes Site Survey Survey on Site PreparationP320W Support Notes P320W Support Notes What is the P320W 802.11g Wireless Firewall Router? FAQDoes the Prestige support PPPoE? What is PPPoE?Will the P320W work with my Internet connection? What do I need to use the Prestige?Which Internet Applications can I use with the Prestige? How do I know I am using PPPoE?Why does my provider use PPPoE? How can I configure the Prestige?How does e-mail work through the Prestige? How fast can the data go? What Dhcp capability does the Prestige support?Your ISP checks the MAC address Your ISP checks the Host Name What is Ddns What is BOOTP/DHCPWhen do I need Ddns service? What makes P320W secure? What is a network firewall?What are the basic types of firewalls? What kind of firewall is the P320W? What is Denials of Service DoS attack?What is Land attack? What is Ping of Death attack?What is Teardrop attack? What is SYN Flood attack?What is a Wireless LAN? What is IP Spoofing attack?What are the advantages of Wireless LANs? Where can you find wireless 802.11 networks? What are the disadvantages of Wireless LANs?What is an Access Point? What is 802.11g? What is Ieee 802.11?What is 802.11b? What is 802.11a?Is it possible to use products from a variety of vendors? What is Wi-Fi?Does the 802.11 interfere with Bluetooth devices? Can radio signals pass through walls?Whats the difference between a Wlan and a WWAN? What is Ad Hoc mode?What is Infrastructure mode? How many Access Points are required in a given area?What is Server Set ID SSID? What is Direct-Sequence Spread Spectrum Technology DSSS?What is Frequency-hopping Spread Spectrum Technology FHSS? Why the 2.4 Ghz Frequency range?What is a WEP key? What is an ESSID?What is WEP? What is the difference between 40-bit and 64-bit WEP?Open System What is Wireless Sniffer?Can the Ssid be encrypted? What are Insertion Attacks?What is AAA? What is 802.1x?What is RADIUS? Why cannot access the Internet? Why cannot access the Prestige from my computer?Your ISP checks the MAC address ZyXEL SUA Supporting Table Unable to run applicationsApplication Outgoing Connection Incoming Connection NAT-T P320W Support Notes