1000Base-T
See Gigabit Ethernet.

100Base-T
An increasingly common Ethernet wiring standard that works almost exactly like 10Base-T, but increases the maximum throughput to 100 Mbps. 100Base-T is often called "Fast Ethernet."

10Base-2
An Ethernet wiring standard that uses thin coaxial cable, has a maximum segment length of 185 meters, runs at 10 Mbps, uses a bus network topology, and isn't in common use any more. 10Base-2 is also called "ThinNet."  

10Base-5
An Ethernet wiring standard that uses thick coaxial cable, has a maximum segment length of 500 meters, uses a bus network topology, runs at 10 Mbps, and isn't in common use any more. 10Base-5 is also called "ThickNet."

10Base-T
The most common Ethernet wiring standard. 10Base-T uses twisted pair wiring that's used to connect buildings' telephone wire to the telephone company, runs at 10 Mbps, uses a star network topology, and is limited to a maximum segment length of 100 meters.

1G
The original analog, voice-only cellular telephone standard, developed in the 1980s. Analog cellular service is being phased out in all but the most rural areas in the United States.

1x
A prefix for cellular data technology that indicates that only 1.25 MHz of spectrum are in use.

1xEV-DO
An upcoming third-generation cellular data technology for CDMA networks in testing by Verizon Wireless. EV-DO stands for Evolution Data Optimized (but is sometimes referred to as Evolution Data Only).

1xEV-DV
An upcoming third-generation cellular data technology for CDMA networks in testing by Sprint PCS and AT&T Wireless. EV-DV stands for Evolution Data/Voice.

1xRTT
A cellular data technology for CDMA networks. RTT stands for Radio Transmission Technology. 1xRTT has a theoretical maximum of 144 Kbps of bandwidth, but achieves a practical throughput of only 50 to 70 Kbps in the real world.

2.5G
Bridging the gap between 2G and 3G cellular service, 2.5G extends CDMA and GSM technologies with faster Web access, Multimedia Messaging Service (MMS), and a change in radio architecture to handle more bandwidth. 2.5G phones can receive digital photos from other 2.5G phones that have built-in or add-on cameras. They can also get your notebook or PDA on the Net, albeit at pokey modemlike speeds. 2.5G and 2G phones and networks are interoperable for basic calling and SMS capability, so if you like your old phone, keep it, but if you want a new phone, rest assured it should work in all the places where your old phone did, as long as you are staying with the same carrier and technology.

2G
Second-generation digital cellular service is the most widely used worldwide. It offers digital voice calling, limited Web-access capability, and Short Message Service (SMS). 2G cell phone standards include CDMA, TDMA, and GSM.

3G
Third-generation mobile communications technology, as defined by the ITU, provides a global standard for cellular networks capable of handling live video calls and data access at broadband speeds. There are several flavors of 3G, including EDGE, CDMA 2000, and WCDMA/UMTS. A handful of carriers are moving from GSM to EDGE and from CDMA to CDMA 2000, but the reigning champ for an emerging global 3G standard is WCDMA/UMTS, which has already started rolling out in Europe. Expect to see a lot of hoopla about 3G in 2004 and beyond.

3x
A prefix for a future third-generation CDMA cellular network that will use 5 MHz of spectrum, or 3 times the 1x spectrum use.

802.11
A family of specifications related to wireless networking. See 802.11a, 802.11b, and 802.11g.

802.11a
One of three wireless networking specifications under the Wi-Fi rubric. 802.11a uses the 5 GHz band and runs at 54 Mbps. 802.11a is little used outside specific business situations.

802.11b
The most common of the three wireless networking specifications included in the Wi-Fi certification mark. 802.11b uses the 2.4 GHz band and runs at 11 Mbps.

802.11e
A wireless standard that provides Quality of Service support for LANs. This is necessary for delay-sensitive applications such as Voice over Wireless IP. The standard is under development and isn't expected until 2004.

802.11g
The newest of the three Wi-Fi specifications. 802.11g is backward compatible with 802.11b, thanks in part to its use of the 2.4 GHz band, and it runs at the 54 Mbps speed of 802.11a. Most new equipment uses 802.11g.

802.11h
A supplementary standard to 802.11 to comply with European regulations. It adds transmission power control and dynamic frequency selection.

802.11i
A standard for improving wireless LAN security over 802.11a and 802.11b. It adds new encryption protocols, including Temporal Key Integrity Protocol and Advanced Encryption Standard. The 802.11i standard encrypts data sent along wireless networks to protect it from anyone who may intercept it. The most significant feature of the 802.11i standard is Advanced Encryption Standard (AES), a strong encryption standard supporting 128-bit, 192-bit and 256-bit keys.

802.11n
A draft standard reportedly in the works that would boost 802.11a and 802.11b speeds to 108 Mbps and higher. 802.11n is not yet official and isn't expected to be complete until 2005 at the earliest.

802.11r
A draft standard wiich is meant to improve the roaming of clients as they move from network to network. 802.11r is not yet official and isn't expected to be complete until 2005 at the earliest.

802.16
The technical name for WiMax. 802.16 and a subset, 802.16a, are used for long-haul and backhaul connections.

802.1X
An authentication specification that allows a client to connect to a wireless access point or wired switch but prevents the client from gaining access to the Internet until it provides credentials, like a user name and password, that are verified by a separate server. In 802.1X, there are three roles: the supplicant (client), authenticator (switch or access point), and authentication server.

ACCESS POINT
The hub of a wireless network. Wireless clients connect to the access point, and traffic between two clients must travel through the access point. Access points are often abbreviated to AP in industry literature, and you may also see them referred to as "wireless routers," "wireless gateways," and "base stations." We prefer to use "access point" when discussing true access points that don't also share Internet connections or bridge between wired and wireless networks.

AD-HOC NETWORK
A wireless network composed of stations without Access Points.

AD-HOC NETWORK
A short-term wireless network created between two or more wireless network adapters without going through an access point. Ad hoc networks are handy for quickly trading files when you have no other way of connecting two or more computers.

AD-HOC CONNECTIONS
Spur-of-the-moment connections made for a specific reason and then shut down. Most uses of infrared communications are for ad hoc connections.

AD-HOC MODE
An informal way of creating a wireless network between two or more computers without the need for a centralized access point.

ADAPTER
A computer add-in board device used to connect end-user nodes to the network; each contains an interface to a specific type of workstation or system bus, e.g. EISA, ISA, MCA, PCI, etc.

ARP (Address Resolution Protocol)
TCP/IP Interior Gateway Protocol for dynamically mapping Internet addresses to physical hardware addresses on LANs; limited to LANs that support hardware broadcast.

Asymmetric Digital Subscriber Line (ADSL)
A technology for transmitting digital information at a high bandwidth on existing phone lines to homes and businesses. Unlike regular dialup phone service, ADSL provides continously-available, "always on" connection. ADSL is asymmetric in that it uses most of the channel to transmit downstream to the user and only a small part to receive information from the user.

ASYNCHRONOUS TRANSFER MODE (ATM)
A specific packet-oriented transfer mode using asynchronous time division multiplexing technique: the multiplesec information flow is organised in fixed blocks called cells (Also called cell-relay).

ATM (Asynchronous Transfer Mode)
A high-speed, connection-oriented switching technology that can transmit voice, video, and data traffic simultaneously through fixed-length packets called cells.

ATTACHMENT UNIT INTERFACE (AUI)
Connector found on many network cards and 10BASE-T hubs, used to attach yellow cable via a transceiver.

AUTO-SENSING
Procedure for defining connection-speed for 10/100Mbps Ethernet devices and Ethernet transceivers.

AUTO-NEGOTIATION
A signalling method that allows each node to define its operational mode (e.g., 10 Mbps or 100 Mbps and to detect the operational mode of the adjacent node.

AES
An extremely strong encryption standard that's just starting to become available. AES stands for Advanced Encryption System.

AGGREGATOR
A company that resells access to other companies' wireless networks.

AirPort
Apple's marketing name for its 802.11b wireless networking technology.

AirPort Extreme
Apple's marketing name for its 802.11g wireless networking technology.

AMPLIFIER
A device you can connect to your antenna to increase the signal strength and amplify weak incoming signals.

AMPS
Advanced Mobile Phone Service, the standard for analog cellular in the United States. See 1G.

ANTENNA
A device connected to a wireless transceiver that concentrates transmitted and received radio waves to increase signal strength and thus the effective range of a wireless network. To accept an antenna, a device must have an appropriate antenna jack.

APOP
A protocol for protecting email passwords used with POP. APOP stands for Authenticated Post Office Protocol.

AppleTalk
A network protocol used primarily by older Macs and LaserWriter printers. If you have such hardware, you must ensure that any access points you buy support AppleTalk.

AUTHENTICATE
The process of confirming the identity of someone connecting to a network.

AUTHENTICATION
The process of identifying a user, usually by a user name and password. The next generation of Wi-Fi security, Wi-Fi Protected Access, or WPA, will use authentication to verify whether users have access to a particular wireless network.

AUTHENTICATION SERVER
A back-end database server that confirms the identity of a supplicant to an authenticator in an 802.1X-authenticated network.

AUTHENTICATOR
The gatekeeper role in an 802.1X-authenticated network. You can think of the authenticator as a gatekeeper; access points and Ethernet switches can act as authenticators.

BANDWIDTH
Transmission capacity of a computer channel, communications line or bus. It is expressed in cycles per second (Hertz), the bandwidth being the difference between the lowest and highest frequencies transmitted. It is also often stated in bits or bytes per second.

BACK-PRESSURE
A technology that prevents data collisions when the network line is busy.

BBAE
Name for a ADSL-Splitter (Broadband-Connection-Unit)

BNC
Commonly used connector for coaxial cable. After the plug is inserted, the socket is turned, causing the pins to tighten the plug within it.

Bootrom (or BootPROM)
A chip installed on the network card, that typically contains networking software to start a remote-boot client.

BOOTP (Boot Protocol)
Protocol used for the static assignment of IP addresses to devices on the network.

BRIDGE
The simplest of the Internetworking devices, the bridge connects two networks together. Bridges function at the data link layer of the OSI Model by selectively forwarding data (independent of software protocol) between two networks. Bridges can be used to connect or segment the traffic on networks.

BUS
An electrical connection which allows two or more lines to be connected together. Circuit cards with the proper address will be able to access the appropriate information from the bus, as the same information travels to all destinations.

BACKHAUL
Connecting Internet access to a location over long or short distances. Traditionally, wired networks have been necessary for backhaul, but with 802.16, also known as WiMax, backhaul via wireless will become even more common than it is with Wi-Fi.

BAND
Another term for spectrum used to indicate a particular set of frequencies. Wireless networking protocols work in either the 2.4 GHz or the 5 GHz bands.

BANDWIDTH
See throughput.

BASE STATION
See wireless gateway.

BASEBAND
The original band of frequencies of a signal before it is modulated for transmission, as in multiplexing. See multiplex.

Bluetooth
A short-range wireless cable replacement technology.

BREW
Binary Runtime Environment for Wireless, an open system created by Qualcomm for delivering over-the-air applications and data. The hottest use for BREW to date has been downloadable games.

BRIDGE
A device that passes traffic between two networks that use different media or are physically separate, but which use similar network standards. Common uses for bridges include connecting wired and wireless networks, connecting a HomePlug network to a wireless network, and connecting distant wireless networks (with the aid of antennas).

BRIDGING
The act of connecting two networks via a bridge.

BSS
Basic Service Set. See IBSS.

BUS NETWORK
A network topology in which all the computers connect to a single wire. Bus networks are also sometimes called "daisy-chain" networks, and they aren't commonly used any more.

CBR (Constant Bit Rate)
CBR is related to Class A Quality of Service and often associated with premium transmission service.

CCK (Complementary Code Keying)
CCK is the coding method associated with 802.11b wireless devices.

CCK-OFDM
An optional transmit mode defined by the IEEE802.11g standard that combines the access modes of IEEE802.11a and IEEE802.11b; capable of supporting transmission speeds of up to 22Mbps.

CHAP (Challenge Handshake Authentication Protocol)
Security feature supported on lines using PPP encapsulation that prevents unauthorized access. CHAP does not itself prevent unauthorized access, it merely identifies the remote end. The router or access server then determines whether that user is allowed access.

CLASS I REPEATER
Fast Ethernet repeater that performs translations when transmitting or repeating incoming signals to enable different physical media to be connected to the same collision domain; which may have a MII interface.

CLASS II REPEATER
Fast Ethernet repeater that immediately transmits or repeats incoming signals to other devices on identical media.

COLLISION DOMAIN
See CSMA/CD.

CSMA/CA (Carrier Sense Multiple Access / Collision Avoidance)
Multiple access scheme that uses Direct Sequence Spread Spectrum (DSSS) code sequences as traffic channels in a common radio channel.

CSMA/CD (Carrier Sense Multiple Access / Collision Detect)
Protocol from Ethernet Standard. A multiple access scheme (used in 802.3 LANs) that relies upon a station being able to listen for a collision while transmitting.

CABLE MODEM
A device that hooks to your cable TV line to allow your computer to receive data at about 1.5 Mbps. The theoretical maximum for downstream transactions is 27 Mbps and 2.5 Mbps upstream, but the connection is usually much slower because the provider may be hooked to the Internet via a T-1 line.

CAPTIVE PORTAL
A Web page that appears automatically when you try to access any URL when first connected to some public wireless networks. On the captive portal page, you must enter login information or agree to acceptable use policies before you can use the wireless network to do anything else.

CAT5
The only type of twisted pair wire you should buy for Ethernet networks. Cat3 isn't rated for 100 Mbps.

CDMA
The type of digital cellular phone network used throughout most of the United States, but rare elsewhere in the world. CDMA stands for Code Division Multiple Access, and CDMA2000 is the third-generation, or 3G, extension to which CDMA cellular operators are gradually upgrading their networks.

CDPD
Cellular Digital Packet Data, a specification that supports wireless access to the Internet or other public networks. It uses packet switching, so a persistent link isn't needed, making it especially useful for mobile devices. CDPD is quickly being replaced by higher-speed services in 2.5G and 3G cellular networks.

CELL
The geographic area covered by a cellular telephone transmitter. A connected group of cells form a cell system, which is what you gain access to when you sign up for cellular telephone service.

CENTRINO
A marketing name developed and promoted by Intel for laptops that use the Pentium-M processor, an Intel Pro/Wireless mini-PCI adapter, and some of Intel's support chips. Intel also requires some compatibility testing before manufacturers can use the Centrino name.

CERTIFICATE
An instantiation of a digital identity. Certificates are typically signed by other people or certificate authorities to guarantee their authenticity.

CERTIFICATE AUTHORITY
A trusted third party that can assure the identity of others when using security systems like SSL. A certificate authority registers the digital identity of a site or individual, and lets you confirm manually or automatically that someone you're interacting with -- say, over a secure Web connection -- is who he appears to be.

CHANNEL
A specific portion of the radio spectrum; for example, the channels allotted to one of the wireless networking protocols. 802.11b and 802.11g use 14 channels in the 2.4 GHz band, only 3 of which don't overlap (1, 6, and 11). In the 5 GHz band, 802.11a uses 8 channels for indoor use and 4 others for outdoor use, and none of them overlap.

CIRCUIT-SWITCHED NETWORK
A network in which a virtual circuit is set up for each connection in order to simulate having a physical wire between two points. The telephone system is a circuit-switched network. Circuit-switched networks are generally considered less efficient than packet-switched networks like the Internet because the circuit remains reserved even when no data is being transferred (i.e. when no one is talking).

CLEAR TEXT
Sensitive information like passwords sent across a network without encryption. Clear text is also commonly referred to as "in the clear."

CLIENT ASSOCIATION
The process by which a wireless client -- like a laptop computer -- connects to an access point.

CLIENT CARD
An add-on that gives a computer or PDA or similar device wireless capability.

CLONING
The act of replicating one device's MAC address onto another to work around restrictions that prevent only particular MAC addresses from connecting to a network. Also sometimes called "spoofing."

CLOSED NETWORK
A wireless network that doesn't advertise its network name.  

COLLISION
The interference that results when two devices on a network start transmitting at the same time.

COMPUTER-TO-COMPUTER NETWORK
See ad hoc network.

CROSSOVER CABLE
Ethernet cable that has the transmit and receive pins switched. You use a crossover cable to connect certain kinds of network devices, like hubs.

CTIA
Cellular Telecommunications & Internet Association, a wireless industry organization. CTIA holds annual trade shows and serves as the industry's representative in dealings with regulatory agencies, such as the FCC.

DAISY CHAIN NETWORK
See bus network.

DoS (Denial of Service)
A DoS attack floods a network with an overwhelming amount of traffic, slowing its response time for legitimate traffic or grinding it to a halt completely.

Direct sequence spread spectrum (DSSS)
A type of spread spectrum radio transmission that spreads its signal continuously over a wide frequency band.

Direct sequence spread spectrum (DSSS)
One of two approaches (with frequency hopping spread spectrum) for sorting out overlapping data signals transmitted via radio waves. Direct sequence spread spectrum is commonly abbreviated to DSSS or DS. 802.11b uses direct sequence spread spectrum.

DSSS
Direct-Sequence Spread Spectrum is a system for generating spread-spectrum transmissions. It generates a redundant pattern for each bit to be transmitted, called a chipping code. Using this, the signal is split over several frequencies, and the different parts are sent concurrently. This method is faster than FHSS, but is more sensitive to environmental factors. Wi-Fi transmissions use DSSS.

DSLAM (Digital Subscriber Line Access Multiplexer)
Network device, usually at a telephone company central office, that receives signals from multiple customer Digital Subscriber Line (DSL) connections and puts the signals on a high-speed backbone.

dBi
Ratio of decibels to an isotropic antenna that is commonly used to measure antenna gain. The greater the dBi value, the higher the gain, and the more acute the angle of coverage.

Diversity Antennas
An intelligent system of two antennas that continually senses incoming radio signals and automatically selects the antenna best positioned to receive it.

DMZ (Demilitarized Zone)
A neutral zone or buffer that separates internal and external networks. The DMZ usually exists between two firewalls. External users can access servers in the DMZ, but not the computers on the internal network. The servers in the DMZ act as an intermediary for both incoming and outgoing traffic.

DMZ (Demilitarized Zone)
A feature in a NAT gateway that lets you expose a machine on your internal network to the outside Internet. DMZ nominally stands for demilitarized zone, and is sometimes also called "virtual server." It's basically port mapping for all available ports.

DECIBELS
The unit used for measuring antenna gain. Decibels are abbreviated as dB, and you may also see dBm (decibels relative to a reference level of 1 milliwatt) and dBi (decibels relative to an isotropic radiator, or a single point antenna).

DHCP
A protocol by which a server automatically assigns IP addresses to clients so users doesn't have to configure them manually. DHCP stands for Dynamic Host Configuration Protocol.

DIPOLE ANTENNA
An antenna type that offers omnidirectional coverage, but not much gain. Access points usually have one or two dipole antennas to increase their gain slightly.

DISCOVERABLE
The state in which a Bluetooth device must be to be seen by another Bluetooth device for pairing.

DISCOVERY
The act in Bluetooth of finding a discoverable device within range for pairing.

DNS
An Internet protocol for mapping cryptic IP addresses (like 198.65.100.241) to human-readable domain names (like jiwire.com). DNS stands for Domain Name Service.

DoCoMo
Japan's largest mobile service provider. Its claim to fame is i-mode, a service that gives subscribers continuous access to the Internet via mobile phones, and it is Japan's largest Internet access platform.

DSL
A common form of broadband Internet connection. DSL stands for Digital Subscriber Line.

DUAL-BAND
A description of a wireless phone that works on two frequencies. In the United States, these are typically the original cellular (800MHz) and newer PCS (1900MHz) frequencies.

DYNAMIC DNS
A technique that lets people connect a permanent domain name to an ever-charging IP address.

EAP
A standard form of generic messaging used in 802.1X, among other places. EAP stands for Extensible Authentication Protocol.

EAP-TLS
Used to create a secured connection for 802.1X by pre-installing a digital certificate on the client computer. EAP-TLS stands for Extensible Authentication Protocol-Translation Layer Security.

ELECTRONIC MAIL
Transmitted signals go to the first device and from the first to the second and so on. Transmission of memos and messages over a network.

EliteView
SMC’s windows-based Network Management Software. Free of charge available for download on www.smc.com or www.smc-europe.com.

EISA
Extended ISA, PC bus standard that extends the AT bus (ISA bus) to 32 bits and provides bus mastering. It was announced in 1988 as a 32-bit alternative to the Micro Channel that would preserve investment in existing boards. PC and AT cards (ISA cards) can also plug into EISA slots.

ETHERNET
The most common networking standard in the world, formally known as IEEE 802.3.

ETHERNET BACKBONE
The wired Ethernet network you use to connect access points in a roaming network.

ETSI (European Telecommunication Standards Institute)
Organization created by the European PTTs and the European Community (EC) to propose telecommunications standards for Europe.

E911
Enhanced 911, an emergency service that automatically sends phone number and location information to the operator. E911 comes in handy, say, when you need to get emergency help and are unable to speak or don't know your location.

EDGE
An upcoming cellular data technology for GSM networks. EDGE atands for Enhanced Data GSM Environment and should provide more than 100 Kbps of bandwidth.

ENCAPSULATED
A way of wrapping protocols such as TCP/IP, AppleTalk, and NetBEUI in Ethernet frames so they can traverse an Ethernet network and be unwrapped when they reach the destination computer.

ENCRYPTION
The process of scrambling data to make it difficult for unauthorized parties to understand. Pretty Good Privacy is a commonly used encryption scheme employing public and private keys; a message is encrypted using the recipient's public key and decrypted with the associated private key. Without the private key, the encrypted message is gibberish.

ESN
Electronic Serial Number, a unique identification number assigned to every cellular phone. ESNs are used by cellular phone systems to identify phones making and receiving calls.

ESS
Extended Service Set A set of two or more BSSes working together to form a single network.

ESSID
Extended Service Set Identifier. See network name.

FAST ETHERNET SWITCH
A device that provides full 100 Mbps or 10 Mbps bandwidth to each port (segment).

FAST ETHERNET
See 100Base-T.

FAULT TOLERANT
A method of making a computer or network system resistant to software errors and hardware problems. A fault tolerant LAN system tries to ensure that even in the event of a power failure, a disk crash or a major user error, data is not lost and the system can keep running.

FIBRE DISTRIBUTED DATA INTERFACE (FDDI)
ANSI (American National Standards Institute) standard token passing LAN that uses optical fiber cabling and transmits at 100Mbps. FDDI provides a quantum leap in speed over Ethernet, Token Ring and other LANs and allows high-resolution graphics and digital video to be quickly transmitted.

FRAGMENT-FREE FORWARDING
A type of forwarding method used in switches that allows data to be forwarded through after the first 64bytes of each data packet is checked due to the data error rate condition of the network.

FARADAY CAGE
An electromagnetic shield, which may be simulated in a house by chicken wire supporting plaster on the walls.

FAST HANDOFF
A way that access points can let authenticated users roam among different access points without losing authentication. Fast handoff also makes voice-over-IP possible. Fast handoff will be made possible with the 802.11f specification.

FHSS
Frequency-Hopping Spread Spectrum changes, or hops, frequencies in a pattern known to both sender and receiver. Contrast to DSSS. FHSS is little influenced by radio stations, reflections, or other environmental factors, but it is much slower than DSSS. Bluetooth uses this technology.

FINGERPRINT
A short sequence of characters you can send someone so she can verify that a specific public key is actually your public key.

FIREWALL
A network program that blocks malevolent traffic that might endanger the computers on your network.

FIRMWARE
The internal software that runs dedicated hardware devices. Upgrades to firmware are often necessary to fix problems.

FIXED WIRELESS
The operation of wireless devices in a specific location, such as an office. This term is usually reserved for devices that need to be plugged in to operate, such as a desktop computer. If it runs off a battery, it's not fixed wireless.

FRAME
A packet encapsulated to travel on a physical medium, like Ethernet or Wi-Fi. A packet is like a shipping container; a frame is the boat on which the shipping container is loaded.

FRAME BURSTING
An approach to increasing the speed of 802.11g-based wireless networks by unwrapping short 802.11g packets and rebundling them into a larger packet to reduce the impact of mandatory gaps between packets. Frame bursting is sometimes called "packet bursting."

FREQUENCY HOPPING SPREAD SPECTRUM
One of two approaches (with direct sequence spread spectrum) for sorting out overlapping data signals transmitted via radio waves. Frequency hopping spread spectrum is commonly abbreviated to FHSS or FH. Bluetooth uses frequency hopping spread spectrum.

FRESNEL ZONE
An elliptical area on either side of the straight line of sight that must also be clear for a long-range wireless network to work.

FTP
A common way of transferring files on the Internet, though it's primarily used for uploading these days. FTP stands for File Transfer Protocol.

GBIC (Gigabit Interface Converter)
A transceiver used to connect Gigabit Ethernet port to a specific medium.

Gbps (Gigabit per second)
1Gbps = 125 Megabyte per second

GAIN
The amount by which an antenna concentrates signal strength in a wireless network.

GATEWAY
See wireless gateway.

GIGABIT ETHERNET
An up-and-coming Ethernet wiring standard that works almost exactly like 10Base-T, but increases the maximum throughput to 1000 Mbps, or roughly 1 Gbps. Gigabit Ethernet is more technically known as "1000Base-T."

GIGAHERTZ
A measure of electromagnetic wave frequency equal to one thousand million (1,000,000,000) hertz, often abbreviated as GHz and used to specify the radio frequency used by wireless devices. 802.11a networks operate at 5Ghz. 802.11b and g networks use 2.4Ghz, which is susceptible to interference from nearby cordless phones and microwave ovens that use the same frequency.

GPRS
A cellular data technology for GSM networks. GPRS stands for General Packet Radio Service and provides between 10 and 50 Kbps of bandwidth.

GPS
Global Positioning System, a technology that uses satellites to pinpoint a device's location on Earth. Some new cell phones include GPS capability for location-based services, such as driving directions or pinpointing your location when you call 911.

GSM
The primary type of digital cellular phone network used throughout most of the world outside the United States, and a growing standard in the U.S. GSM stands for Global System for Mobile Communications. GSM provides a very slow (9600 bps) cellular data service.

HANDSHAKE
The exchange of information between two modems as they negotiate which communication protocol to use. The funny sounds you hear when your computer initiates a dial-up connection are the modems handshaking.

HUB
Central switching device for communications lines in a star topology. It may add nothing to the transmission (passive hub) or may contain electronics that regenerate signals to boost strength as well as monitor activity (active/intelligent hub). Hubs may be added to bus topologies; for example, a hub can turn an Ethernet network into a star topology to improve troubleshooting.

HUB
The central device in a star network, whether wired or wireless. Wireless access points act as hubs in wireless networks.

HANDOFF
The act of switching coverage responsibility from one base station to another. It usually refers to what happens when a wireless phone user moves from one cell to another.

HEADER
Address information on packets that says where it should go.

HIGH-GAIN ANTENNA
An antenna that significantly increases signal strength. High-gain antennas are necessary for long-range wireless networks.

HOME GATEWAY
See wireless gateway.

HOMEPLUG
A networking standard that uses standard electrical wiring. HomePlug is primarily useful for bridging wireless networks across obstacles (like brick walls) that block radio waves. HomePlug runs at 14 Mbps.

HOME PNA
A networking standard that uses standard telephone wiring. HomePNA is primarily useful for bridging wireless networks across obstacles (like brick walls) that block radio waves. HomePNA 2.0 runs at 10 Mbps, and the just-defined HomePNA 3.0 runs at 128 Mbps, in theory.

HOME RF
A now-defunct competitor to Wi-Fi that integrated voice, data, and streaming media into a single wireless signal.

HOT SPOT
A place where you can connect to a public wireless network.

HTTP
The network protocol used by the Web, although it's also now used for many other services. HTTP stands for Hypertext Transfer Protocol.

INFRASTRUCTURE MODE
A client setting providing connectivity to an Access Point. As compared to Ad-Hoc Mode where PCs communicate directly with each other, clients set in Infrastructure Mode all pass data through a central AP.

INFRASTRUCTURE MODE
The most common way of creating a wireless network in which clients associate with an access point.

INFRASTRUCTURE BSS
An 802.11 network comprising an access point and stations. The access point forwards information to target stations or to a fixed network.

INTERNET
Large network made up of a number of smaller networks.

INTERRUPT REQUEST (IRQ)
Hardware interruption on a PC. Eight lines (0-7 on 8086/88s) and 16 lines (0-15 on 286 and up) accept interruption from input devices, such as a scanner and network adapter.

INTERNATIONAL STANDARDS ORGANISATION (ISO)
Organisation that sets international standards, founded in 1946 and headquartered in Geneva.

IPSEC (Internet Protocol Security)
Framework for a set of Protocols for security at the network or packet processing layer of network communication.

ISA bus
Original PC bus architecture, refers to the 16-bit AT bus. ISA Industry Standard Architecture. The most common bus architecture on the motherboard of MS-DOS computers. The ISA bus was originally pioneered by IBM on its PC, the n its XT and AT. ISA is also called classic bus. It comes in an 8-bit and 16-bit version. Most references to ISA mean the 16-bit version. Many machines claiming ISA compatibility will have both 8 and 16-bit connectors on the motherboard.

IBSS
Independent Basic Service Set, also known as an ad hoc network. It is an 802.11 network comprising a collection of stations that communicate with each other, and not with a network infrastructure. Do not confuse with Infrastructure BSS.

iDEN
Integrated Digital Enhanced Network, a wireless technology from Motorola which combines digital cellular, paging, two-way radio, and modem capabilities on a single network.

IEEE
Institute of Electrical and Electronics Engineers. The acronym is pronounced I-triple-ee, and the organization develops standards for the computer and electronics industry, such as Wi-Fi.

IEEE 802.11
802.11 is a family of wireless networking standards developed by the IEEE, including 802.11a, 80211b, and 80211g. 802.11a provides up to 54 Mbps on the 5GHz band. 802.11b hits 11 Mbps in the 2.4GHz band and is backward-compatible with 802.11, the original specification. 802.11g, the most recently approved, provides over 20 Mbps on the 2.4GHz band. It is compatible with 802.11b. Both 802.11b and 802.11g have effective ranges of about 300 feet; 802.11a's higher frequency limits its range to about 60 feet. Other standards in this family include 802.11e, 802.11h, and 802.11n.

IEEE 802.15
A communications specification for wireless personal area networks. The original version was adapted from Bluetooth, and it is compatible with Bluetooth 1.1.

IEEE 802.16
A standard designed for fixed broadband wireless access. It is used in WirelessMAN (Wireless Metropolitan Area Network) setups, which feature a controlling base station that connects subscriber stations not to each other but to various public networks, such as the Internet, linked to the base station.

IEEE 802.20
This standard is under development. The goal is to provide fully mobile broadband wireless access for native Internet Protocol traffic.

IMAP
An increasingly common way of receiving email from a mail server on the Internet. IMAP defaults to storing mail on a server, in contrast to POP, which stores mail on your computer. IMAP stands for Internet Message Access Protocol.

IP
Internet Protocol, the method by which data is sent from one computer to another on the Internet.

IP ADDRESS
The numeric address (like 192.168.1.1) that identifies each device in a TCP/IP network.

IPSEC
One of two protocols (with PPTP) used for VPNs. IPsec stands for IP security.

IrDA
Infrared Data Association, an industry organization that creates standards for hardware and software used in infrared communications. Information is transferred via rays of light, as opposed to radio waves. Most TV remote controls use infrared.

ISDN
Integrated Services Digital Network, a method for sending digital data over copper telephone wires. ISDN can provide speeds up to 128 Mbps.

MIB (Management Information Base)
A group of management procedures implemented in a network device for the purpose of remote device control and monitoring operations via an SNMP agent.

MII
(Media Independent Interface), the standard interface interface for traditional Ethernet.

MT-RJ
A type of small form factor fibre connector that uses the RJ-type of latching mechanism found on most copper cable connectors. The MT-RJ connector can be spaced the same as traditional copper connectors making fibre-optic cable installations easier and more cost efficient modem: A modem modulates outgoing digital signals from a computer or other digital device to analog signals for a conventional copper twisted pair telephone line and demodulates the incoming analog signal and converts it to a digital signal for the digital device. From early 1998, most new personal computers came with 56 Kbps modems.

Multicast
A type of network transmission in which a frame is sent to a series of related devices on a network, including a set of switches, a specific subnetwork, or all devices of a specific manufacturer.

MULTI-TASKING
Running two or more programs in one computer at the same time. It is controlled by the operating system. The number of programs that can be effectively multi-tasked depends on the a mount o f memory available, CPU speed, hard disk capacity and speed, as well as the efficiency of the operating system.

MAC ADDRESS
The unique address assigned to every wireless and wired Ethernet network adapter. MAC stands for Media Access Control. Despite the fact that MAC addresses are all unique, it's possible to assign one device's MAC address to another device.

MASTER ACCESS POINT
The primary access point in a wireless network that uses WDS to extend range. The master access point shares the Internet connection with the rest of the remote, or relay access points, along with all the wireless clients.

Mbps
Megabits per second, or millions of bits per second, a measure of bandwidth.

MEGAHERTZ
A measure of electromagnetic wave frequency equal to one million (1,000,000) hertz, often abbreviated as MHz and used to specify the radio frequency used by wireless devices.

MESH NETWORK
A network topology in which every device can communicate with any other device that's within range. Mesh networking is particularly interesting for bringing wireless network access to an entire neighborhood.

MICROBROWSER
Software designed for portable wireless devices, such as cell phones, that allows users to download Internet content that's specially formatted for small screens.

MICROCELL
A cell having a very small coverage area, such as a lounge in an airport terminal.

MMS
Multimedia Messaging Service, which allows users to send messages containing text, pictures, sounds, and other rich media between cell phones.

MOBILE IP
A communications protocol designed to allow mobile users to maintain their permanent IP address while moving from network to network.

MODEM
Short for modulator/demodulator. A modem modulates outgoing digital data into analog signals so they can be sent over copper phone lines, and demodulates incoming analog signals into digital.

MPEG-4
A standard for delivering streaming multimedia content to wireless devices. An example of the technology in action might be the ability to watch movie trailers on your wireless phone.

MULTIPLEX
o combine multiple signals for transmission over a single channel. For example, a Wi-Fi connection uses Orthogonal Frequency Division Multiplexing, which spreads the signal power over a large band. It breaks the signal into parts, enabling a fast transmission that is sent as several slower transmissions simultaneously, using different frequencies.

NETWARE
Novell's family of network operating systems that runs on 286 PCs and up and supports DOS, OS/2 and Mac work stations. It works with a variety of LAN access methods, including Token Ring, Ethernet, ARCNET and Starlan.

NETWORK
A set of communication channels interconnecting several or many locations.

NETWORK
A collection of interconnected computers and associated devices. Networks can be characterized by the protocols they use (TCP/IP, for example) or by the geographic area they cover (LAN and WAN).

NETWORK INTERFACE CARD
Commonly abbreviated to NIC. See network adapter.

NETWORK INTERFACE CARD (NIC)
Interface card required in the expansion bus of a personal computer to connect to the cabling of a LAN.

NIC
Network Interface Card or adapter that enables terminals to connect to an network line.

NETWORK MANAGEMENT
Procedures, software, equipment and operations designed to keep a network operating near maximum efficiency.

NETWORK DIAMETER
Wire distance between two end stations in the same collision domain.

NAT
A network service that makes it possible to share a single IP address with a network of many computers. NAT stands for Network Address Translation. Since a NAT gateway exposes only a single IP address to the outside Internet, it's useful for security, and some manufacturers may call it, somewhat incorrectly, a "firewall."

NetBEUI
An older networking standard developed by IBM for LAN Manager and adopted for use in Microsoft Windows. NetBEUI stands for NetBIOS Extended User Interface.

NETWORK ADAPTER
The card or built-in hardware used in a computer or handheld device to connect to a network, whether wired or wireless.

NETWORK DIAGRAM
A rough picture of a proposed or existing network. Network diagrams are extremely useful for planning new networks and for troubleshooting problems with existing networks.

NETWORK NAME
The name you give to your network; it's what shows up when a wireless client displays available networks. Many manufacturers use the terms "SSID" or "ESSID" in place of network name.

NETWORK SEGMENTS
Physically and logically separate sections of a network. Breaking a network into segments increases bandwidth by reducing the amount of traffic that each device must listen to.

NETWORK TOPOLOGY
The specific layout of a network.

OSPF (Open Shortest Path First Protocol)
Routing protocol for TCP/IP routers that bases routing decisions on the least number of hops from source to destination.

OPEN NETWORK
A wireless network that is broadcasting its name.

PCI bus
Local bus for PCs from Intel that provides a high-speed data path between the CPU and up to 10 peripherals (video, disk, network, etc.). The PCI bus runs at 33MHz, support s 32-bit and 64-bit data paths, and bus mastering.

PCMCIA NIC (PC Card)
A credit card size I/O package for computers, laptops, and palmtops. The three standards of PCMCIA cards are Type I, II, and III. The Type II standard applies to NICs, is used for I/O features and can operate on Ethernet or Token Ring hardware.

PLUG AND PLAY
A mechanism by which I/O devices are configured automatically upon installation.

PORT
1.The entrance or physical access point to a repeater, computer, multiplexer, device or network where signals may be supplied, extracted or observed.

2.To convert software to run in a different computer environment.

PORT MIRRORING
Method of monitoring network traffic that forwards a copy of each incoming and outgoing packet from one port of a network switch to another port where the packet can be studied.

PPP
A network protocol that handles dial-up Internet connections. PPP stands for Point-to-Point Protocol.

PPPoE
A technology that enables an ISP to require users to log in to an always-on Internet connection, something that wouldn't otherwise be necessary. PPPoE stands for PPP over Ethernet.

PPPoA (PPP over ATM)
Data packets are exchanged over ATM.

PROTOCOL
Rules governing transmitting and receiving of data.

PROTOCOL
See specification.

PACKET
A discrete chunk of data, being transferred on a TCP/IP or other addressable network.

PACKET BURSTING
See frame bursting.

PACKET-SWITCHED NETWORK
A network in which data is transferred in discrete chunks, called packets. The Internet is a packet-switched network. Packet-switched networks are generally considered more efficient than circuit-switched networks like the telephone system because multiple connections can use the same network simultaneously.

PAIRING
The act of introducing two Bluetooth devices to each other so they can communicate.

PANEL ANTENNA
An antenna type that radiates in only a specific direction. Panel antennas are commonly used for point-to-point situations. You may also see them called "patch antennas."

PARABOLIC ANTENNA
An antenna type that radiates a very narrow beam in a specific direction. Parabolic antennas offer the highest gain for long-range point-to-point situations.

PASS-THROUGH
See port mapping.

PASSIVE FTP
An option in FTP in which a connection starts from port 21 and the server replies using port 21 as well, instead of a higher numbered port, as it would normally.

PASSPHRASE
One or more words you must enter to authenticate both sides of the connection when pairing Bluetooth devices. Some manufacturers may use the terms "password" or "passkey" instead. More generically, you may see passphrase used in place of "password" to indicate that you can enter more than a single word.

PATCH ANTENNA
See panel antenna.

PATCH CABLE
A normal Ethernet cable, as opposed to a crossover cable.

PCS
Personal Communications Services, a higher frequency, digital wireless phone service similar to cellular. It operates in the 1850-1900MHz band, while traditional cellular uses 824-849MHz.

PEAP
A method of securing an 802.1X session within an encrypted tunnel to protect credentials used for logging in. PEAP stands for Protected Extensible Authentication Protocol.

PERSONAL CERTIFICATE
A certificate you generate for use with SSL that doesn't have a certificate authority behind it. Personal certificates, also known as "self-signed certificates," aren't secure, but they're good enough in cases where you're working with your own SSL-enabled systems.

PGP
A technology and set of programs for encrypting data. PGP stands for Pretty Good Privacy.

PHONENET
An adapter that enabled LocalTalk networks to operate over standard silver-satin telephone wiring, rather than Apple's proprietary LocalTalk cables.

PIGTAIL
A thin cable that connects an antenna to a wireless network adapter, usually converting between plug types in the process.

PLAIN TEXT
See clear text.

PLENUM-RATED
A term used describe Ethernet cable that has slow-burning, fire-resistant casing that emits little smoke. Plenum-rated Ethernet cable is used in overhead ductwork.

POINT-TO-MULTIPOINT
A wireless network in which one point (the access point) serves multiple other points around it. Indoor wireless networks are all point-to-multipoint, and long-range wireless networks that serve multiple clients usually employ either a single omnidirectional antenna or multiple sector antennas.

POINT-TO-POINT
A long-range wireless network between two points. Point-to-point wireless networks use directional antennas.

POP
The most common way of receiving email from a mail server on the Internet. POP defaults to storing mail on your computer, in contrast to IMAP, which stores mail on the server. POP stands for Post Office Protocol.

PORT
Either a physical jack on a network device or a way of identifying the type of data being sent in an Internet connection. Every Internet service has its own port number.

PORT FORWARDING
See port mapping.

PORT MAPPING
The act of mapping a port on an Internet-accessible NAT gateway to another port on a machine on your internal network. Port mapping enables you to run a public Internet service on a machine that is otherwise hidden from the Internet by your NAT gateway. Other names for port mapping include "port forwarding," "pass-through," and "punch-through."

POWER OVER ETHERNET (PoE)
A wiring scheme that lets you run electrical power to an access point or wireless bridge over the same Ethernet cable that connects the device to your network. Power over Ethernet is often abbreviated to PoE.

PPTP
One of two protocols (with IPsec) used for VPNs. PPTP stands for Point-to-Point Tunneling Protocol.

PRE-SHARED KEY
A TKIP passphrase used to protect your network traffic in WPA. Some manufacturers use the term "pre-shared secret" instead.

PRE-SHARED SECRET
See pre-shared key.

PRIVATE KEY
The key you keep secret in public-key cryptography systems. You use your private key to decrypt encrypted data sent to you by other people, who used your public key to encrypt it. You also use your private key to sign email messages; your recipients then use your public key to verify your signature.

PROMISCUOUS MODE
A state of a wireless network adapter in which it listens to all the traffic on a wireless network rather than just the traffic addressed to your computer.

PUBLIC KEY
The key you give out to the world in public-key cryptography systems. Other people use your public key when sending you encrypted data, which you can then decrypt with your private key. You also use other people's public keys to verify the authenticity of mail messages they've signed with their private keys.

PULLING WIRE
The act of running network cabling from one location to another. Wireless networks generally obviate the need to pull wire, which is one of their great attractions. HomePlug and Home-PNA can also help you avoid pulling wire.

PUNCH-THROUGH
See port mapping.

RIP (Routing Information Protocol)
RIP teaches routers on a wide area network which routers have access to which addresses. RIP bases its routing path on the distance (number of hops) to the destination. RIP maintains optimum routing paths by sending out routing update messages if the network topology changes.

RMON (Remote Network Monitoring)
Provides standard information that a network administrator can use to monitor, analyze, and troubleshoot a group of distributed local area networks (LANs).

ROAMING
In wireless communications, the movement by a user among many cells or zones. The term implies that the system can locate the handset as it "roams" and provide continuing service.

ROAMING
The act of seamlessly moving your wireless connection from one access point to another as you walk around. To enable roaming between access points, connect them to the same wired Ethernet network, give them the same network name, and set them to use different, non-overlapping channels (1, 6, and 11).

ROUTER
In communications, a device that examines the destination address of a message and selects the most effective route. A router receives physical layer signals from a network, performs data link and network layer protocol processing, then sends the signals via appropriate data link and physical layer protocols to another network.

ROUTER
An intelligent network device that goes one step beyond bridging by converting address-based protocols that describe how packets move from one place to another. In practice, this generally comes down to translating between IP addresses and MAC addresses for data flowing between your local network and the Internet. Many people use the term interchangeably with "gateway." You must enter the IP address of your router when configuring network settings manually.

RECEIVE SENSITIVITY
The capability of a radio transceiver to receive weak signals. The lower the receive sensitivity, the more capable the transceiver is of understanding weak signals.

RELAY ACCESS POINT
See remote access point.

RELAYING
The act of sending email through your mail server when you're not connected to your local network. Spammers take advantage of mail servers that allow unrestricted relaying.

REMOTE ACCESS POINT
One of a number of secondary access points in a wireless network that uses WDS to extend its range. Remote access points, sometimes also called "relay access points," connect to a master access point.

RFID
Radio Frequency Identification, a technology used to uniquely identify objects. A transceiver (say, at a highway toll booth) sends out a signal that activates a transponder (a tag installed in a car, for example), which sends data back to the transceiver (let me through, I've already paid).

RING NETWORK
A network topology similar to a bus network, but with the ends of the wire connected to form a ring. Ring networks are uncommon today.

RJ-11
A plug type used by telephones. Don't confuse it with the larger RJ-45 plug type used in Ethernet networks.

RJ-45
A plug type used in Ethernet networks. Don't confuse it with the smaller RJ-11 plugs used for phone cables.

SEGMENT
A separate LAN or collision domain.

SEGMENTABLE STACK
Stackable Hubs capable fo subdividing the LAN into separate collision domains.

SERVER
A computer that is on the network and shares resources with other network users. The server may be dedicated, which means that its sole purpose is to provide service for network users, or it may be used as a client.

SHARED PORTS
Ports that are on the same collision domain and share a fixed bandwidth.

SIMPLE NETWORK MANAGEMENT PROTOCOL (SNMP)
Format used for network management data. Data is passed between SNMP agents (processes that monitor activity in hubs, routers, bridges, etc.) and the workstation used to oversee the network. SNMP uses Management Information Bases (MIBs), which are databases that define what information is obtainable from a networked device and what can be controlled (turn off, on, etc.).

SMARTWATCH
The term used to monitor all critical activities within a Hub or Switch.

Sniffer
Program that monitors and analyzes network traffic, detecting bottlenecks and problems. Using this information, a network manager can keep traffic flowing efficiently.

SPANNING-TREE ALGORITHM
A technology that checks your network for any loop configurations. A loop can often occur in complicated or back-up linked network systems. Spanning-tree detects and directs data along the shortest line to its destination, maximising the performance and efficiency of the network.

SPI Firewall
Firewall that inspects incoming data packets to make sure they correspond to an outgoing request. Unsolicited - and possibly harmful - packets are rejected.

Splitter
Device that divides a telephone signal into two or more signals, each carrying a selected frequency range, and can also reassemble signals from multiple signal sources into a single signal. The telephone company's central office also uses a POTS splitter to send low-frequency voice signals on to the voice telephone network and to send high-frequency data to a Digital Subscriber Line Access Multiplexor (DLSAM) for transmission to the Internet.

SSID (Service Set Identifier)
Sequence of characters that uniquely names a wireless local area network (WLAN). This name allows stations to connect to the desired network when multiple independent networks operate in the same physical area.

SSL (Secure Sockets Layer)
Protocol for managing the security of a message transmission on the Internet. SSL is included as part of both the Microsoft and Netscape browsers and most Web server products.

ST
Straight through cable (commonly used for building networks).

STORE & FORWARD
A type of forwarding method used in switches that allows data to be forwarded through after it has been fully checked due to the high error rate of the network. STP (Shielded twisted-pair) cable.

SWITCH
A high-performance, multi-port bridge that subdivides, or microsegments, the network into smaller networks and then interconnectsthesegments to enable them to communicate with each other.

SWITCHED PORTS
Ports that are on separate collision domains or segments.

SCRIPT KIDDIES
Wanna-be crackers who don't have the technical skills to break into computers on their own, so they use canned cracking software.

SECTOR ANTENNA
An antenna type that radiates in only a specific direction. Multiple sector antennas are commonly used in point-to-multipoint situations.

SELF-SIGNED CERTIFICATE
See personal certificate.

Sharespot™ Access Point
End-user access points made available for public use and registered with a third-party agency, ISP, or community user group capable of monitoring each location's uptime and availability. JiWire now lists Sharespot™ access points in its hotspot directory and promptly deletes locations which can no longer be verified by their respective third parties. For more information about Sharespot listings, send email to data@jiwire.com.

SIGNAL DIVERSITY
A process by which two small dipole antennas are used to send and receive, combining their results for better effect.

SIGNAL LOSS
The amount of signal strength that's lost in antenna cable, connectors, and free space. Signal loss is measured in decibels.

SIGNAL STRENGTH
The strength of the radio waves in a wireless network.

SILVER SATIN
A wiring type in which pairs of wires run side-by-side. Silver satin is used for plugging in telephones; don't use it for networking.

SMART CARD
A card containing data about a person's identity and credentials to allow access to a network or physical site.

SMS
Short Message Service, a method for sending text messages of about 200 characters to GSM mobile phones. Messages are delivered at low cost and nearly instantaneously. If the recipient's phone is turned off, messages are held and re-delivered.

SMTP
The protocol for sending email on the Internet. SMTP stands for Simple Mail Transfer Protocol.

SMTP AUTH
A command in the SMTP protocol that requires identification before an SMTP server will accept outgoing mail from you. SMTP AUTH is essentially authenticated SMTP.

SNIFFER
In wireless parlance, a sniffer is software or a hardware device that searches for the presence of a wireless network. Another type of sniffer is software used to analyze or intercept wired network traffic.

SOFTWARE ACCESS POINT
A wireless-enabled computer running special software that enables it to act exactly like an wireless access point.

SPECIFICATION
In the networking world, a formal language used by different devices to communicate. Agreed-upon specifications become standards. Specification is generally interchangeable with the term "protocol."

SPECTRUM
A range of electromagnetic frequencies.

SPREAD SPECTRUM
A form of wireless communication in which a signal's frequency is deliberately varied. This increases bandwidth and lessens the chances of interruption or interception of the transmitted signal.

SSH
A security system that lets you create encrypted tunnels for any Internet protocol via port forwarding. SSH stands for Secure Shell.

SSID
Service Set Identifier, a set of characters that give a unique name to a WLAN.

SSL
A security protocol that secures Internet transactions at the program level. SSL, which stands for Secure Sockets Layer, is widely used in Web browsers to protect credit card transactions, for instance. SSL is a component in EAP-TLS (Extensible Authentication Protocol-Transport Layer Security).

STANDARD
A specification that has been agreed-upon by enough parties or given a stamp of approval by an industry body.

STAR NETWORK
A network topology in which all traffic goes through a central hub. Most wireless networks are star networks.

STUMBLER
A software program that looks for available wireless networks in range and reports information about them.

SUBNET MASK
A network setting that indicates the size of the network you're on.

SUPPLICANT
The client role in an 802.1X-authenticated network.

SWITCH
A specific type of hub that isolates the communications between any two computers from the rest of the network, thus increasing throughput. Switches are also called "switching hubs."

SYMBIAN
An open operating system designed for cell phones that supports multimedia messaging, Bluetooth, and Java.

T-1, T-3
Transmission systems commonly used in the Internet. T-1 provides a continuous, dedicated transmission rate of up to 1.5 Mbps, T-3 44.7 Mbps. T-1 and T-3 lines are expensive and generally for business or science use, not consumer use.

TDMA
Time Division Multiple Access, a way to deliver digital wireless service. TDMA works by dividing a frequency into time slots and allocating them to multiple calls. TDMA is the standard on which GSM is based, but GSM phones will not work on TDMA networks and vice versa.

THICKNET
See 10Base-5.

THINNET
See 10Base-2.

THROUGHPUT
The amount of data that can be transmitted in a given amount of time. Throughput is commonly measured in bits per second. (Although throughput is not really a measurement of speed, most people, including us, use the word "speed" when talking about a high-throughput network.)

TKIP
An encryption key that's part of WPA. TKIP stands for Temporal Key Integrity Protocol. It's nominally weaker than the government-grade AES, but in the real world, TKIP is more than strong enough.

TLS
Transport Layer Security. See SSL.

TRANSMIT POWER
The amount of power used by a radio transceiver to send the signal out. Transmit power is generally measured in milliwatts, which you can convert to dBm.

TRI-BAND
A description of a wireless phone that works on three bands. CDMA and TDMA tri-band phones work on 1900MHz and 800MHz digital frequencies, and 800MHz analog cellular--popular standards in the United States. Tri-band GSM phones are all digital, operating on 1900Mhz in the United States and 1800Mhz and 900Mhz in other countries.

TRIGGER
A special form of port mapping in which outgoing traffic on a specific port alerts a NAT gateway to allow incoming traffic on other ports. Triggers are used for network gaming.

TWISTED PAIR
A wiring type in which each pair of wires twists in a certain way to reduce electromagnetic interference. 10Base-T, 100Base-T, and Gigabit Ethernet all use twisted pair wires. Compare twisted pair to silver-satin telephone wire, in which the pairs don't twist, and which thus cannot be used for networking.

USB (Universal Serial Bus)
Plug-and-Play interface between a computer and add-on devices (such as audio players, joysticks, keyboards, telephones, scanners, and printers). With USB, a new device can be added to your computer without having to add an adapter card or even having to turn the computer off.

ULTRA WIDEBAND
A wireless networking approach that broadcasts millions of tiny pulses at trillionth-of-second intervals using very low power over enormous swaths of spectrum. In comparison, traditional radios broadcast continuously on tiny bits of spectrum. Ultra Wideband is commonly abbreviated to UWB.

UNSHIELDED TWISTED PAIR
The most common type of twisted pair wiring. Unshielded twisted pair lacks a shield to act as a ground. Unshielded twisted pair is often abbreviated to UTP.

UPLINK PORT
A special port on a hub or switch that has the transmit and receive pins switched, so you can use a normal patch cable instead of a crossover cable to connect it to other hubs. Many hubs now come with ports that you can switch between normal and uplink status, and others can automatically sense whether they should switch from normal to uplink status, depending on which device is connected to them.

VIRTUAL SERVER
Presents a single address that represents an application server farm to clients.

VOICE-OVER-IP
A way of making telephone calls over a packet-switched network like the Internet. Voice-over-IP requires special telephones and software. Voice-over-IP is commonly abbreviated to VoIP.

VoIP
Short for Voice over IP, which is simply voice data sent using Internet Protocol over the public Internet or an intranet. Its main advantage is that it avoids the usual phone service tolls. A few companies are offering cordless VoIP phones that work on Wi-Fi networks.

VPN
A method of creating an encrypted tunnel through which all traffic passes, preventing anyone from snooping through transmitted and received data. VPN stands for virtual private network.

WEP
An encryption system for preventing eavesdropping on wireless network traffic. WEP stands for Wired Equivalent Privacy. WEP is easily broken, and is in the process of being replaced by WPA.

Wi-Fi (Wireless Fidelity)
Wi-Fi originally referred to the 802.11b specification for WLANs, but it is now used to describe any of the IEEE802.11 wireless networking specifications.

Wi-Fi
A certification mark managed by a trade group called the Wi-Fi Alliance. Wi-Fi certification encompasses numerous different standards, including 802.11a, 802.11b, 802.11g, WPA, and more, and equipment must pass compatibility testing to receive the Wi-Fi mark.

WiMax
Another name for the 802.16 wireless networking specification used for long-haul and backhaul connections.

WORKGROUP
Two or more individuals who share files and databases. LANs designed around workgroups provide electronic sharing of required data.

WORKSTATION
1.High-performance, single user microcomputer or minicomputer that has been specialised for graphics, CAD, CAE or scientific applications. Typically comprised of high resolution screens, local graphics processing, keyboard, pointing device, and network connection.

2.In a LAN, a personal computer that serves a single user in contrast with a file server that serves all users in the network.

3.Any terminal or personal computer

WPA
A modern encryption system for preventing eavesdropping on wireless network traffic that solves the problems that plagued WEP. WPA stands for Wi-Fi Protected Access.

WAN
Wide Area Network, A collection of local area networks connected by a variety of physical means. The Internet is the largest and most well-known wide area network. Wide area network is generally abbreviated to WAN.

WAP
Wireless Application Protocol, a set of standards to enable wireless devices to access Internet services, such as the World Wide Web and email.

WARCHALKING
The act of making hobo-inspired chalk marks on walls or sidewalks to indicate the presence of wireless networks. Warchalking is more media hype than reality.

WARDRIVING
The act of driving around with your laptop open, looking to see if you can connect to open wireless networks as you drive. Change the mode of transportation and you get "warwalking," "warcycling," and "warflying."

WDS
A technology that enables access points to communicate with one another in order to extend the range of a wireless network. WDS is appearing in 802.11g-based access points, and it stands for Wireless Distribution System.

WIRELESS ACCESS POINT
See access point.

WIRELESS GATEWAY
A somewhat generic term that we use to differentiate between an access point and a more-capable device that can share an Internet connection, serve DHCP, and bridge between wired and wireless networks. You may also see the term "wireless router," or "base station."

WIRELESS ISP
A company that provides wireless Internet access. The term is often abbreviated to WISP.

WIRELESS NETWORK ADAPTER
See network adapter.

WIRELESS ROUTER
See wireless gateway.

WLAN
Wireless Local Access Network, a LAN that can be connected to via a wireless connection.

WPAN
Wireless Personal Area Network, a wireless network designed around one person and the devices he or she uses, such as a PDA, mobile phone, and portable computer, covering a relatively small area. The Bluetooth technology was developed with WPANs in mind.