Glossary of Networking Terms
Posted February 20th, 2007 by admin
Computer Network Terms
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
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802.11a
An IEEE wireless networking standard that specifies a maximum data transfer rate of 54Mbps and an operating frequency of 5GHz.
802.11b
An IEEE wireless networking standard that specifies a maximum data transfer rate of 11Mbps and an operating frequency of 2.4GHz.
802.11g
An IEEE wireless networking standard that specifies a maximum data transfer rate of 54Mbps, an operating frequency of 2.4GHz, and backward compatibility with 802.11b devices.
Access Point
A device that allows wireless-equipped computers and other devices to communicate with a wired network. Also used to expand the range of a wireless network.
Adapter
A device that adds network functionality to your PC.
Ad-hoc
A group of wireless devices communicating directly with each other (peer-to-peer) without the use of an access point.
AES (Advanced Encryption Standard)
A method that uses up to 256-bit key encryption to secure data.
Amplifier
A device used to boost the strength of an electronic or optical signal, which is weakened (attenuated) as it passes through the transport network. Amplifiers add gain to the signal by an amount equal to the loss in the previous section of the network since last amplification.
Asymmetric Digital Subscriber Line (ADSL)
A new technology that allows more data to be sent over existing copper telephone lines. ADSL supports data rates of from 1.5 to 9 Mbps when receiving data (known as the downstream rate) and from 16 to 640 Kbps when sending data (known as the upstream rate).
Asynchronous Transfer Mode (ATM)
A method of sending audio, visual and computer data at the same time over one high-speed digital line.
Backbone
The part of a network that connects most of the systems and networks together, and handles the most data.
Bandwidth
The transmission capacity of a given device or network.
Beacon Interval
Data transmitted on your wireless network that keeps the network synchronized.
Bit (Binary Digit)
The smallest unit of information on a machine.
Boot
To start a device and cause it to start executing instructions.
Bridge
A device that connects two different kinds of local networks, such as a wireless network to a wired Ethernet network.
Broadband
A transmission channel usually carrying a tremendous amount of information. A communications channel with a bandwidth sufficiently large to carry voice, data and video on a signal channel. Any voice communications channel having a bandwidth greater than a voice-grade channel.
Broadcast storm
An incorrect packet broadcast onto a network that causes multiple hosts to respond all at once, typically with equally incorrect packets which causes the storm to grow exponentially in severity.
Browser
An application program that provides a way to look at and interact with all the information on the World Wide Web.
Buffer
A shared or assigned memory area that is used to support and coordinate different computing and networking activities so one isn't held up by the other.
Burst Mode
A way of doing data transmission, usually faster than normal transmission mode, in which a continuous block is transferred between main memory and an input/output device without interruption until the transfer has been completed. Characteristically, burst mode is sustainable for only limited periods of time under special conditions.
Byte
A unit of data that is usually eight bits long.
Cable Modem
A device that connects a computer to the cable television network, which in turn connects to the Internet.
Challenge-Handshake Authentication Protocol (CHAP)
An authentication method that can be used when connecting to an Internet Service Provider. CHAP allows you to log in to your provider automatically, without the need for a terminal screen.
Checksum
A computed value which is dependent upon the contents of a packet. This value is sent along with the packet when it is transmitted. The receiving system computes a new checksum based upon the received data and compares this value with the one sent with th packet. If the two values are the same, the receiver has a high degree of confidence that the data was received correctly.
Circuit switching
A communications paradigm in which a dedicated communication path is established between two hosts, and on which all packets travel. The telephone system is an example of a circuit switched network.
Client
A computer system or process that requests a service of another computer system or process. A workstation requesting the contents of a file from a file server is a client of the file server.
Client-server model
A common way to describe the paradigm of many network protocols. Examples include the name-server/name-resolver relationship in DNS and the file-server/file-client relationship in NFS.
Compression
Algorithm that minimizes the redundancy in the signal to be transmitted.
Core Layer
The Cisco hierarchical network design model defines the core layer as the high-speed switching backbone that should be designed to switch packets as fast as possible. These devices typically accept uplinks from “distribution layer” switches, connections to “border devices”. QUT’s core network layer consists of high speed switches / routers.
Congestion
Congestion occurs when the offered load exceeds the capacity of a data communication path.
Connection Oriented
The data communication method in which communication proceeds through three well-defined phases: connection establishment, data transfer, connection release. TCP is a connection-oriented protocol.
Connectionless
The data communication method in which communication occurs between hosts with no previous setup. Packets between two hosts may take different routes, as each is independent of the other. UDP is a connectionless protocol.
Cryptography
The process of concealing the contents of a message from all except those who know the key. Cryptography is used to protect e-mail messages, credit card information, and corporate data. As the Internet and other forms of electronic communication become more prevalent, electronic security is also becoming increasingly important.
CSMA/CA(Carrier Sense Multiple Access/Collision Avoidance)
A method of data transfer that is used to prevent data collisions.
CTS (Clear To Send)
A signal sent by a device to indicate that it is ready to receive data.
Daisy Chain
A method used to connect devices in a series, one after the other.
Database
A collection of data that is organized so that its contents can easily be accessed, managed, and updated
Datagram
A self-contained, independent entity of data carrying sufficient information to be routed from the source to the destination computer without reliance on earlier exchanges between this source and destination computer and the transporting network.
DCE
Data Circuit-terminating Equipment.
DDNS (Dynamic Domain Name System)
Allows the hosting of a website, FTP server, or e-mail server with a fixed domain name (e.g., www.xyz.com) and a dynamic IP address.
Default Gateway
A device that forwards Internet traffic from your local area network.
DECnet
A proprietary network protocol designed by Digital Equipment Corporation. The functionality of each Phase of the implementation, such as Phase IV and Phase V, is different.
Default route
A routing table entry which is used to direct packets addressed to networks not explicitly listed in the routing table.
DHCP (Dynamic Host Configuration Protocol)
A protocol that lets one device on a local network, known as a DHCP server, assign temporary IP addresses to the other network devices, typically computers.
Distribution Layer
The Cisco hierarchical network design model defines the distribution layer of the network as the demarcation point between the access and core layers of the network. This layer includes LAN-based routers and layer 3 switches. Any switch that aggregate “access layer devices” back to the “core layer” is known as a “distribution device”. At QUT a mixture of layer2 and layer3 switches are used in the distribution layer to support access layer switches and servers / hosts requiring gigabit Ethernet connections.
DMZ (Demilitarized Zone)
Removes the router's firewall protection from one PC, allowing it to be "seen" from the Internet.
DNS (Domain Name Server)
The IP address of your ISP's server, which translates the names of websites into IP addresses.
The DNS is a general purpose distributed, replicated, data query service. The principal use is the lookup of host IP addresses based on host names. The style of host names now used in the Internet is called "domain name", because they are the style of names used to look up anything in the DNS. Some important domains are: .COM (commercial), .EDU (educational), .NET (network operations), .GOV (U.S. government), and .MIL (U.S. military). Most countries also have a domain. For example, .US (United States), .UK (United Kingdom), .AU (Australia). It is defined in STD 13, RFCs 1034 and 1035.
Domain
A specific name for a network of computers.
Download
To receive a file transmitted over a network.
DSI
A digital transmission hierarchy supporting 1.544 million bits per second that may be used for "near-full motion" or compressed video, data or voice circuits (24, 48, or 96).
DSL (Digital Subscriber Line)
An always-on broadband connection over traditional phone lines.
DSSS (Direct-Sequence Spread-Spectrum)
Frequency transmission with a redundant bit pattern resulting in a lower probability of information being lost in transit.
DTIM (Delivery Traffic Indication Message)
A message included in data packets that can increase wireless efficiency.
Dynamic IP Address
A temporary IP address assigned by a DHCP server.
E-1
Similar to the North American T-1, E-1 is the European format for digital transmission. E-1 carries signals at 2.048 Mbps (32 channels at 64 Kbps), versus the T-1, which carries signals at 1.544 Mbps (24 channels at 64 Kbps). E-1 and T-1 lines may be interconnected for international use.
E3
A term for a digital carrier facility used to transmit a CEPT3 formatted digital signal at 34.368 megabits per second. Encapsulation
EAP (Extensible Authentication Protocol)
A general authentication protocol used to control network access. Many specific authentication methods work within this framework.
EAP-PEAP (Extensible Authentication Protocol-Protected Extensible Authentication Protocol)
A mutual authentication method that uses a combination of digital certificates and another system, such as passwords.
EAP-TLS (Extensible Authentication Protocol-Transport Layer Security)
A mutual authentication method that uses digital certificates.
Encapsulation
The technique used by layered protocols in which a layer adds header information to the protocol data unit (PDU) from the layer above. As an example, in Internet terminology, a packet would contain a header from the physical layer, followed by a header from the network layer (IP), followed by a header from the transport layer (TCP), followed by the application protocol data.
Encryption
Encryption is the manipulation of data to prevent accurate interpretation by all but those for whom the data is intended. There are many types of data encryption, and they are the basis of network security.
Ethernet
An IEEE standard network protocol that specifies how data is placed on and retrieved from a common transmission medium.
Ethernet Switch
High performanace segmentation ethernet frame soluation, increases performance.
Fault Tolerance
The ability of a system to respond gracefully to an unexpected hardware or software failure. There are many levels of fault tolerance, the lowest being the ability to continue operation in the event of a power failure.
Fibre Distributed Data Interface (FDDI)
FDDI is a fibre optic backbone to connect LANs
Fiber Optics
Technology based on thin filaments of glass or other transparent materials used as the medium for transmitting coded light pulses that represent data, image and sound. Fiber-optic technology offers extremely fast transmission speeds.
Finger
A program that tells you the name associated with an e-mail address.
Firewall
A firewall is any of security schemes that prevent unauthorized users from gaining access to a computer network or that monitor transfers of information to and from the network.
Firmware
The programming code that runs a networking device.
FTP (File Transfer Protocol)
A standard protocol for sending files between computers over a TCP/IP network and the Internet. FTP is usually the name of the program the user invokes to execute the protocol.
Fragment
A piece of a packet. When a router is forwarding an IP packet to a network that has a maximum packet size smaller than the packet size, it is forced to break up that packet into multiple fragments. These fragments will be reassembled by the IP layer at the destination host.
Fragmentation
The IP process in which a packet is broken into smaller pieces to fit the requirements of a physical network over which the packet must pass.
Frame
A frame is a datalink layer "packet" which contains the header and trailer information required by the physical medium. That is, network layer packets are encapsulated to become frames.
Full Duplex
The ability of a networking device to receive and transmit data simultaneously. Full duplex is sometimes called "Echo On" by some communications programs.
Fully Qualified Domain Name (FQDN)
The FQDN is the full name of a system, rather than just its hostname. For example, "pigsfly" is a hostname and "pigsfly.home.edu.ca" is an FQDN.
Gateway
A device that interconnects networks with different, incompatible communications protocols. The term "router" is now used in place of the original definition of "gateway". Currently, a gateway is a communications device/program which passes data between networks having similar functions but dissimilar implementations. This should not be confused with a protocol converter. By this definition, a router is a layer 3 (network layer) gateway, and a mail gateway is a layer 7 (application layer) gateway.
Gbps (Gigabits per second)
A data rate of 1 Gbps corresponds to 1,000 million bits per second.
Half Duplex
Data transmission that can occur in two directions over a single line, but only one direction at a time.
Hardware
The physical aspect of computers, telecommunications, and other information technology devices.
Hacker
A slang term for a computer enthusiast. Also refers to individuals who gain unauthorized access to computer systems for the purpose of stealing and corrupting data.
Header
The portion of a packet, preceding the actual data, containing source and destination addresses, and error checking and other fields. A header is also the part of an electronic mail message that precedes the body of a message and contains, among other things, the message originator, date and time.
Heterogeneous network
A network running multiple network layer protocols.
High Performance Parallel Interface (HIPPI)
HIPPI is used to network supercomputers, high-end workstations and peripherals using cross-bar type circuit switches. It provides for transfer rates of 800 Mbps over 32 twisted pair copper wires (single HIPPI) and 1,600 Mbps over 64 pairs (double HIPPI).
Host
A computer that allows users to communicate with other host computers on a network. Individual users communicate by using application programs, such as electronic mail, Telnet and FTP.
Hub
A device connected to several other devices. In ARCnet, a hub is used to connect several computers together. In a message handling service, a hub is used for the transfer of messages across the network.
HTTP (HyperText Transport Protocol)
The communications protocol used to connect to servers on the World Wide Web.
IEEE (The Institute of Electrical and Electronics Engineers)
An independent institute that develops networking standards.
Infrastructure
Currently installed computing and networking equipment.
Infrastructure Mode
Configuration in which a wireless network is bridged to a wired network via an access point.
Internet
A fabric of interconnected computer networks, originally known as the DARPA network (Defense Advanced Research Projects Agency) connecting government and academic sites. It currently links millions of people worldwide who use it for everything from scientific research to simple e-mail.
Internet Control Message Protocol (ICMP)
ICMP is an extension to the Internet Protocol. It allows for the generation of error messages, test packets and informational messages related to IP.IP (Internet Protocol)A protocol used to send data over a network.
Internetwork Packet eXchange (IPX)
Novell's protocol used by Netware. A router with IPX routing can interconnect LANs so that Novell Netware clients and servers can communicate.
IP Address
An Internet address that is a unique number consisting of four parts separated by dots, sometimes called a "dotted quad." For example, 198.204.112.1. Every Internet computer has an IP address and most computers also are assigned one or more domain names that are easier to remember than the dotted quad.
IPCONFIG
A Windows 2000 and XP utility that displays the IP address for a particular networking device.
IPSec (Internet Protocol Security)
A VPN protocol used to implement secure exchange of packets at the IP layer.
ISM band
Radio bandwidth utilized in wireless transmissions.
ISP (Internet Service Provider)
A company that provides access to the Internet.
LAN (Local Area Network)
The computers and networking products that make up the network in your home or office.
Layer
Communication networks for computers may be organized as a set of more or less independent protocols, each in a different layer (also called level). The lowest layer governs direct host-to-host communication between the hardware at different hosts; the highest consists of user applications. Each layer builds on the layer beneath it. For each layer, programs at different hosts use protocols appropriate to the layer to communicate with each other.
TCP/IP has five layers of protocols; OSI has seven. The advantages of different layers of protocols is that the methods of passing information from one layer to another are specified clearly as part of the protocol suite, and changes within a protocol layer are prevented from affecting the other layers. This greatly simplifies the task of designing and maintaining communication programs.
Latency
The amount of time it takes a packet to travel from source to destination. Together, latency and bandwidth define the speed and capacity of a network.
LEAP (Lightweight Extensible Authentication Protocol)
A mutual authentication method that uses a username and password system.
Local Loop
The physical facility, leased from a local exchange carrier (LEC), which provides connectivity between the customer's location and the carrier's point of presence.
Low Voltage Differential Signaling (LVDS)
A low noise, low power, low amplitude method for high-speed (gigabits per second) data transmission over copper wire.
MAC (Media Access Control) Address
A MAC address is the hardware address of a device connected to a shared network medium.
Mbps (Megabits Per Second)
One million bits per second; a unit of measurement for data transmission.
Media Gateway Control Protocol (MGCP)
A proposed control and signal standard for the conversion of audio signals carried on telephone circuits to data packets carried over the Internet or other packet networks. Unlike regular phones, IP phones and devices are not fixed to a specific switch, so they must contain processors that enable them to function independently from a central switching location. MGCP eliminates the need for complex, processor-intense IP telephony devices, thus simplifying and lowering the cost of these terminals.
Medium
The material used to support the transmission of data. This can be copper wire, coaxial cable, optical fibre, or electromagnetic wave (as in microwave).mIRCAn Internet Relay Chat program that runs under Windows.
Multicasting
Sending data to a group of destinations at once. The ability of one network node to send identical data to a number of end servers on the multicast backbone. For large amounts of data, IP multicasting is more efficient than normal Internet transmissions because the server can broadcast a message to multiple recipients simultaneously.
Multilink Point-to-Point Protocol (MP)
MP allows multiple physical connections between two points to be combined into a single logical connection called a bundle. MP supports dynamic bandwidth allocation, which means that physical links can be added or removed from the bundle as needed.
Multimedia
The electronic conversation between two or more people or groups of people in different places using two or more types of digitally integrated communication for voice, sound, text, data, graphics, video, image or presence at the same time. Applications include conferencing, presentations, training, referencing, games, etc.
Multiplexing
An electronic or optical process that combines two or more lower bandwidth transmissions onto one higher bandwidth signal by splitting the total available bandwidth into narrower bands (frequency division) or by allotting a common channel to several transmitting sources one at a time in sequence (time division).
Multipoint
Pertaining or referring to a communications line to which three or more stations are connected. It implies that the line physically extends from one station to another until all are connected.
MultiProtocol Label Switching (MPLS)
MPLS is a widely supported method of speeding up data communication over combined IP/ATM networks. This improves the speed of packet processing and enhances performance of the network.
NAT (Network Address Translation)
NAT technology translates IP addresses of the local area network to a different IP address for the Internet.
NAT (Network Address Translation) Traversal
A method of enabling specialized applications, such as Internet phone calls, video, and audio, to travel between your local network and the Internet. STUN is a specific type of NAT traversal.
Network
A series of computers or devices connected for the purpose of data sharing, storage, and/or transmission between users.
Network Layer
The OSI layer that is responsible for routing, switching, and subnetwork access across the entire OSI environment.
NNTP (Network News Transfer Protocol)
The protocol used to connect to Usenet groups on the Internet.
Network Time Protocol (NTP)
A protocol that assures accurate local timekeeping with reference to radio and atomic clocks located on the Internet. This protocol is capable of synchronizing distributed clocks within milliseconds over long time periods. It is defined in STD 12, RFC 1119.
Node
A network junction or connection point, typically a computer or work station.
Octet
An octet is 8 bits. This term is used in networking, rather than byte, because some systems have bytes that are not 8 bits long.
OFDM (Orthogonal Frequency Division Multiplexing)
Frequency transmission that separates the data stream into a number of lower-speed data streams, which are then transmitted in parallel to prevent information from being lost in transit.
Optical Fiber
Thin filaments of glass through which light beams are transmitted. Enormous capacity, low-cost, low-power consumption, small space, lightweight, insensitivity to electromagnetic interference characterize this transport media.
OSI
Open Systems Interconnection.
Packet
A unit of data transmitted over a network.
Packet Switching
A process where messages are broken into finite-sized packets that are always accepted by the network. The message packets are sent across different circuit paths. The packets are reassembled into the original message at the end of the circuit.
Passphrase
Used much like a password, a passphrase simplifies the WEP encryption process by automatically generating the WEP encryption keys for Linksys products.
PEAP (Protected Extensible Authentication Protocol)
A protocol for transmitting authentication data, including passwords, over 802.11 wireless networks.
Pipelining
In networking, pipelining is a technique used at the transport layer or data link layer in a layered network architecture that allows for the transmission of multiple frames without waiting to see if they are acknowledged on an individuals basis.
Ping (Packet INternet Groper)
An Internet utility used to determine whether a particular IP address is online.
PoE (Power over Ethernet)
A technology enabling an Ethernet network cable to deliver both data and power.
POP3 (Post Office Protocol 3)
A standard protocol used to retrieve e-mail stored on a mail server.
Port
The connection point on a computer or networking device used for plugging in a cable or an adapter.
PPPoE (Point to Point Protocol over Ethernet)
A type of broadband connection that provides authentication (username and password) in addition to data transport.
PPTP (Point-to-Point Tunneling Protocol)
A VPN protocol that allows the Point to Point Protocol (PPP) to be tunneled through an IP network. This protocol is also used as a type of broadband connection in Europe.
Preamble
Part of the wireless signal that synchronizes network traffic.
RADIUS (Remote Authentication Dial-In User Service)
A protocol that uses an authentication server to control network access.
Repeater
1. Equipment that receives a low-power signal, possibly converting it from light to electrical form, amplifying it or retiming and reconstructing it for transmission. It may need to be reconverted to light for retransmission.
2. An optoelectrical device used at each end and occasionally intermediate points of exceptionally long fiber optic span. Optical input is converted to electrical form to restore a clean signal, which drives lasers that fully restores the optical signal at the original signal strength.
Requests for Comments (RFCs)
Internet standards that have developed within the Internet community since 1969. They have grown to become a large series of numbered Internet informational documents and standards widely followed by commercial software and freeware in the Internet and Unix communities. Few RFCs are standards but all Internet standards are recorded in RFCs. Perhaps the single most influential RFC has been RFC 822, the Internet electronic-mail format standard. RFCs are unusual in that they are floated by technical experts acting on their own initiative and reviewed by the Internet at large, rather than formally promulgated through an institution such as ANSI (American National Standards Institute). For this reason, they remain known as RFCs even after they have been adopted as standards.
RJ-45 (Registered Jack-45)
An Ethernet connector that holds up to eight wires.
Roaming
The ability to take a wireless device from one access point's range to another without losing the connection.
Router
A networking device that connects multiple networks together, such as a local network and the Internet.
RTP (Real-time Transport Protocol)
A protocol that enables specialized applications, such as Internet phone calls, video, and audio, to occur in real time.
RTS (Request To Send)
A networking method of coordinating large packets through the RTS Threshold setting.
Serial Line Internet Protocol (SLIP)
An Internet protocol which is used to run IP over serial lines such as telephone circuits. It allows a packet to traverse multiple networks on the way to its final destination.
Server
Any computer whose function in a network is to provide user access to files, printing, communications, and other services.
SMTP (Simple Mail Transfer Protocol)
The standard e-mail protocol on the Internet.
SNMP (Simple Network Management Protocol)
A widely used network monitoring and control protocol.
Software
Instructions for the computer. A series of instructions that performs a particular task is called a "program".
SOHO (Small Office/Home Office)
Market segment of professionals who work at home or in small offices.
SPI (Stateful Packet Inspection) Firewall
A technology that inspects incoming packets of information before allowing them to enter the network.
Spread Spectrum
Wideband radio frequency technique used for more reliable and secure data transmission.
SSID (Service Set IDentifier)
Your wireless network's name.
Static IP Address
A fixed address assigned to a computer or device that is connected to a network.
Static Routing
Forwarding data in a network via a fixed path.
STM-1
The largest standard circuit unit of capacity, which consists of 155,500 Kbps (equal to 155 Mbps). Thus, each Gbps contains enough capacity for 6.4 STM-1 circuits. While capacity is sold to the largest telecommunications companies in minimum investment units equal to one STM-1 unit, most telecommunications companies buy smaller units at a price higher than the equivalent STM-1 price.
Subnet Mask
An address code that determines the size of the network.
Synchronous Transfer Mode (STM)
New term for traditional TDM switching to distinguish it from ATM.
Switch
1. A device that is the central point of connection for computers and other devices in a network, so data can be shared at full transmission speeds.
2. A device for making, breaking, or changing the connections in an electrical circuit.
T1
An AT&T term for a digital carrier facility used to transmit a DS-1 formatted digital signal at 1.544 megabits per second.
T3
A term for a digital carrier facility used to transmit a DS-3 formatted digital signal at 44.746 megabits per second.
TCP (Transmission Control Protocol)
A network protocol for transmitting data that requires acknowledgement from the recipient of data sent.
TCP/IP (Transmission Control Protocol/Internet Protocol)
A network protocol for transmitting data that requires acknowledgement from the recipient of data sent.
Telnet
A user command and TCP/IP protocol used for accessing remote PCs.
Terminal server
A device which connects many terminals to a LAN through one network connection. A terminal server can also connect many network users to its asynchronous ports for dial-out capabilities and printer access.
Throughput
The amount of data moved successfully from one node to another in a given time period.
Time Division Multiplex (TDM)
A technique for transmitting a number of separate data, voice and/or video signals simultaneously over one communications medium by quickly interleaving a piece of each signal one after another.
TFTP (Trivial File Transfer Protocol)
A version of the TCP/IP FTP protocol that uses UDP and has no directory or password capability.
TKIP (Temporal Key Integrity Protocol)
A wireless encryption protocol that periodically changes the encryption key, making it harder to decode.
TLS (Transport Layer Security)
Is a protocol that guarantees privacy and data integrity between client/server applications communicating over the Internet.
Token Ring
A token ring network consists of a set of nodes serially connected by a transmission medium. Information is transferred sequentially, bit by bit, from one active node to the next.
Topology
The physical layout of a network.
TX RateTransmission Rate.
UDP (User Datagram Protocol)
A network protocol for transmitting data that does not require acknowledgement from the recipient of the data that is sent.
Upgrade
To replace existing software or firmware with a newer version.
Upload
To transmit a file over a network.
URL (Uniform Resource Locator)
The address of a file located on the Internet.
Voice over IP (VoIP)
VoIP is voice communications transmitted over the Internet.
VPN (Virtual Private Network)
A security measure to protect data as it leaves one network and goes to another over the Internet.
WAN (Wide Area Network)
A group of networked computers in a large geographical area. The best example of a WAN is the Internet.
Wavelength
The distance between two crests of a signal or a carrier and is measured in terms of meters, millimeters, nanometers, etc. In lightwave applications, because of the extremely high frequencies, wavelength is measured in nanometers.
Wavelength Division Multiplexing (WDM)
A way of increasing the information-carrying capacity of an optical fiber by simultaneously operating at more than one wavelength. With WDM you can multiplex signals by transmitting them at different wavelengths through the same fiber.
WEP (Wired Equivalency Protocol)
WEP is a security protocol for wireless networks. WEP aims to provide security by encrypting data over radio waves so that it is protected as it is transmitted from one end point to another. A shared key (similar to a password) is used to allow communication between the computers and the router. WEP offers a basic, but satisfactory level of security for wireless data transmission.
WINIPCFG
Windows 98 and Me utility that displays the IP address for a particular networking device.
WLAN (Wireless Local Area Network)
A group of computers and associated devices that communicate with each other wirelessly.
WPA (Wi-Fi Protected Access)
A security protocol for wireless networks that builds on the basic foundations of WEP. It secures wireless data transmission by using a key similar to WEP, but the added strength of WPA is that the key changes dynamically. The changing key makes it much more difficult for a hacker to learn the key and gain access to the network.
WPA2 (Wi-Fi Protected Access 2)
WPA2 is the second generation of WPA security and provides a stronger encryption mechanism through Advanced Encryption Standard (AES), which is a requirement for some government users.
WPA-PersonalA version of WPA that uses long and constantly changing encryption keys to make them difficult to decode.
WPA-EnterpriseA version of WPA that uses the same dynamic keys as WPA-Personal and also requires each wireless device to be authorized according to a master list held in a special authentication server.
xDSL
A term referring to a variety of new Digital Subscriber Line technologies. Some of these varieties are asymmetric with different data rates in the downstream and upstream directions. Others are symmetric. Downstream speeds range from 384 Kbps (or "SDSL") to 1.5-8 Mbps (or "ADSL").