Glossary

Here you will find introduction to network glossary, LAN/WAN terminology, telecommunication terminology such as Router, bandwidth, wireless communication, hubs, modems, multiplexer and topology. You will be able to find different terms such as Hubs, Router, Switch, Ethernet, Raid, coaxial cable, bridge, fiber optic, internet, infrared, email, repeater, segment, thick-net etc and many other terms.

10base2. 10base2 is an Ethernet specification for thin coaxial cables with a signal capacity of 10 mega bits per second and distance range of 185 meters per segment.

10base5. 10bast5 is an Ethernet specification cable with the signal capacity of 10 megabits per second and distance capacity of 500 meters per network segment.

10baseF. 10baseF is an Ethernet specification fiber optic cable with the signal capacity of 10 mega bits per second and with the distance capacity of 2000 meters.

10baseT. 10baseT is an Ethernet specification (category 3,4,5) unshielded twisted pair cable with the signal capacity of 10 mega bits per second and distance capacity of 100 meters

100baseT. 100baseT is an Ethernet specification cable, which transmits data at the rate of 100 mega bits per second with the distance range of 100 meters.

1000baseTx. 1000baseTx is an Ethernet speciation cable, which transmits data at the rate of 1 GB per second with the range of 200 meters per segments.

ATM. ATM is a data link layer communication protocol, which transmits the data at the rate of 155 MBPS and is used to connect two local area networks

Apple Talk: Apple Talk is communication Protocol used on the Local Talk networks as well as on the Ethernet and Token Ring.

AUI Connectors: AUI connector is a 15 pins connector found on the Ethernet cards and is used for attaching coaxial, fiber optic and twisted pair cables.

Backbone: Backbone is a cable to which multiple nodes and workstations are attached.

Bit: Bit is a binary digit in a decimal numbering system. Its value can be from 0 and 1 and 8 bits make a byte and 1024 bytes make one KB.

BNC Connectors: This connector is used to connect coaxial and 10base2 cables.

Bridge: Bridge is a device that is used to connect two network as well to pass the packets between two networks that use the same network protocols.

Cable: Cable is a transmission medium and there are different types of cables that are used in a network like coaxial cable, UTP/STP and fiber optic cables.

Client/Server – A communication system in which one ore more File Servers provides services like, central storage, logon access, data communication management, application storage etc and clients (workstations) get these services. There are different types of servers like FTP Server, Web Server, Database Server, Print Server, Fax Server etc. and each server provides different services according to the data communication requirements.

CSMA/CA – In Carrier Sense Multiple Access Collision Avoidance method each device signals before sending the actual data and this prevents the other devices to send the information thus prevents collision from occurring between two or more devices. This technique is used by Local Talk Networks.

CSMA/CD – In Carrier Sense Multiple Access Collision Detection method the devices, which are ready to send the data, first check the channel or medium for a carrier. If no career is sensed then each computer can send the data. If two computers send the data at the same time then a collision occurs and each computer backs off and wait for a certain amount of time to before it attempts to retransmit. This technique is used by the Ethernet.

Coaxial Cable – Coaxial Cable is consisting of a single copper conductor, which is in the center and is surrounded by a plastic layer for insulation and braided metal outer shield.

Concentrator – Concentrator is a device that used to amplify the electrical signals and it provides the central connection point for the workstations, servers and peripheral devices.

DIN – A DIN is a plug and socket connector consisting of circular pattern of pins and metal sleeve. This type of connectors is mostly used in the keyboard.

Dumb Terminal – Dumb terminal are used to communication with the exclusively with the host and receives all the screen layouts from the host computer and sends all the keyboard entries to the host.

E-mail – Email is an electronic mail message, which is sent from the host computer to the remote computer (which can be anywhere in the world).

End User – End user is a person who executes the applications on the workstations.

Ethernet – Ethernet is a communication protocol, which was invented by Xerox and developed jointly by Xerox Digital Equipment and Intel. Ethernet uses CSMA/CD methods and run over a several types of cables with the speed of 10 Mbps.

Expansion Slot – Expansion slots are the areas in the computer that accepts more input/outputs boards to increase the functionality of the computer

Fast Ethernet – Fast Ethernet is a new Ethernet standard that supports 100 Mbps by using a category 5 twisted pair or fiber optic cables.

Fiber Distributed Data Interface (FDDI) – FDDI is a communication protocol that is used to interconnect two or more local area networks that are often over large distances

Fiber Optic Cable - Fiber optic is a cable, consisting of center glass core surrounded by layers of plastic that transmits data using light rather electricity. Fiber optic cables have the capacity to send and receive more information and over much longer distance. ISPs are connected with each other with the Fiber Optic Cables. Telecommunication companies also use the fiber optic cables.

File Server – File server is a Server Computer that contains the data, applications and gives logon access to the other computers on the network. If the file server is dedicated only then it is connected to the client/server network.

Gigabit Ethernet - Gigabit Ethernet is a Ethernet protocol that raises the data transmission rate up to 1Gbps (gigabits per second. It is used on the high speed backbone of a network.

Gigabyte (GB) – A GB consists of one thousand megabytes or one GB consists of 1 billion byes.

Hub – A hub is a communication device that contains multiple ports. Each computer in a network is directly connected with the each port of the hub. Hubs can be active (where they repeat the signals sent through them) and can be passive (which cannot repeat the signals sent through them. Hub broadcasts the data, which means it sends the data to the every node, unlike in the switches, which only send the data to the destined computers.

Infrared – Infrared are the Electromagnetic waves whose frequency range is above the microwaves, but below that of the visible spectrum.

Intranet – An Internal network of an organization that uses Internet protocols. For example a University’s Intranet, in which the students of the university can access their university computer network through Internet.

Internet – Internet is a global Network used to transmit the data/information using the TCP/IP protocol.

LAN –LAN is a network that connecting computers in a small area. Usually a office or network in a building.

Linear Bus – Linear Bus is a network topology in which each computer attaches directly to a common cable.

LocalTalk – Local Talk is a communication protocol that is invented by Apple Corporations that uses CSMA/CA media access method and transmits data at the speed of 230 kilobits per second.

MAN is a network that connecting computers over a relatively large geographical area, such as two buildings in a city or a network in a city.

MAU or Multi station Access Unit is a Token Ring wiring hub.

Modem Modulator/Demodulator – The devices that convert digital signals to the analog signals and analog signals (telephone wires) to the digital (computer) Devices that convert digital and analog signals.

Multiplexer is a device that allows multiple logical signals to be transmitted across a single physical channel.

Network Modem is a modem connected to a LAN that is accessible from every computer on the network.

Network Interface Card (NIC) is a board that provides data communication capabilities to and from computers.

Network Operating System (NOS) is an operating system, which is designed to pass the information and communicate between more than one computer e.g. include AppleShare, Novell NetWare, and Windows NT Server.

Node a node is an End point of a network connection. A node can be any device attached to a network such as a workstation, file server, printer etc.

Node Devices. Any peripheral devices or computer that is connected to a network

PCMCIA - An expansion slot found in many laptop computers. Peer-to-Peer Network - In this type of communication the resources and files are shared without a centralized management source.

Physical Topology - The physical layout of the network; how the cables are arranged; and how the computers are connected.

Point-to-Point - A direct link between two objects.

Ports - A connection point for a cable.

Protocol -A formal description of a set of rules and conventions that govern how devices exchange information.

RAID (Redundant Array of Inexpensive Disks) - A configuration of multiple disks designed to preserve data after a disk casualty.

RAM (Random Access Memory) - The working memory of a computer where data and programs are temporarily stored. RAM only holds information when the computer is on.

Repeater - A device used in data communication to strengthen a signal as it is passed along the network cable.

RJ-45 - Standard connectors used for unshielded twisted-pair cable.

Router -A device that routes information between interconnected networks. It can select the best path to route a message, as well as translate information from one router to another. It is similar to a super intelligent bridge.

SCSI (Small Computer Serial Interface) - An interface controller that allows several peripherals to be connected to the same port on a computer.

Segment - Refers to a section of cable on a network. In Ethernet networks, two types of segments are defined. A populated or trunk segment is a cable that has one or more nodes attached to it. A link segment is a cable that connects a computer to an interconnecting device, such as a repeater or concentrator, or connects a interconnecting device to another interconnecting device.

Sneaker-Net - Refers to a manual method of sharing files in which a file is copied from a computer to a floppy disk, transported to a second computer by a person physically walking (apparently wearing sneakers) to the second computer, and manually transferring the file from floppy disk to the second computer.

Speed of Data Transfer - The rate at which information travels through a network, usually measured in megabits per second.

Star Topology - LAN topology in which each node on a network is connected directly to a central hub or concentrator.

Star-Wired Ring - A topology that connects communication devices (such as computers and printers) in a complete circle.

Tape Back-Up - Copying all the data and programs of a computer system on magnetic tape. On tape, data is stored sequentially. When retrieving data, the tape is searched from the beginning of tape until the data is found.

Terminator - A device that provides electrical resistance at the end of a transmission line. Its function is to absorb signals on the line, thereby keeping them from bouncing back and being received again by the network.

Thicknet - A thick coaxial cable that is used with a 10Base5 Ethernet LAN.

Thinnet - A thin coaxial cable that is used with a 10Base2 Ethernet LAN.

Token - A special packet that contains data and acts as a messenger or carrier between each computer and device on a ring topology. Each computer must wait for the messenger to stop at its node before it can send data over the network.

Token Ring - A data communication protocol developed by IBM in which computers access the network through token-passing. Usually uses a star-wired ring topology.

Topology - There are two types of topology: physical and logical. The physical topology of a network refers to the configuration of cables, computers, and other peripherals. Logical topology is the method used to pass the information between workstations. Issues involving logical topologies are discussed on the Protocol chapter

Transceiver (Transmitter/Receiver) - A Device that receives and sends signals over a medium. In networks, it is generally used to allow for the connection between two different types of cable connectors, such as AUI and RJ-45.

Tree Topology - LAN topology similar to linear bus topology, except that tree networks can contain branches with multiple nodes.

Twisted Pair - Network cabling that consists of four pairs of wires that are manufactured with the wires twisted to certain specifications. Available in shielded and unshielded versions.

USB (Universal Serial Bus) Port - A hardware interface for low-speed peripherals such as the keyboard, mouse, joystick, scanner, printer, and telephony devices.