Lesson 9 (IT)

network interface card (NIC)

A card that enables one computer to send and receive data to and from another computer.

hub

A central point on a network where computers can connect. The central point is often a switch rather than a hub.

peer-to-peer (P2P) network

A network architecture where all computers have equal responsibilities and all computers can share files with each other.

token ring topology

A network layout in which each individual node is connected to two others, with the first and last coming back to connect to each other, thus completing the ring shape.

bus topology

A network layout in which there is one main trunk, or backbone, that all the various computers and network devices are connected to.

Ethernet

The primary networking technology currently in use. Ethernet defines standards for addressing packets and data and a method for avoiding data conflicts on the network.

network protocols

The rules of initiating, interrupting, and continuing communication on a computer network.

network operating system (NOS)

A set of programs used to manage and secure a network.

star bus topology

A LAN topology wherein two star networks are linked using a bus.

client workstation

A computer intended to be used by one person at a time.

server

A computer that provides information or services to other computers.

router

A device that links two computer networks or that links a local area network to the Internet. A router reads packet addresses and routes packets.

client/server network

A network architecture in which each computer is either a client or a server. Servers are powerful computers dedicated to managing the clients. Clients are PCs on which users run applications. Clients rely on servers for resources.

ring topology

A network layout in which two adjacent computers are connected together so that all computers in the network form a ring. Any message is sent from computer to computer until it reaches its destination.

network administrator

A person who manages a computer network; he or she designed its topology and adjusts the network as needed to suit the organization's needs. The network administrator may also be responsible for securing the network against attack.

firewall

A piece of hardware or software on a network designed to limit access to certain machines to authorized users only.

intranet

A private network that looks and functions a lot like the Internet but is typically available only to the employees of an organization.

star topology

A topology with one central node that has each computer or network device attached to the central node. All data first goes into the central node and then is sent out to its destination. (Think of it like a bicycle wheel with spokes.)

coaxial cable

A type of electrical cable often used to transmit cable TV.

switch

A type of hub that uses a table to keep track of destinations so that data can be sent directly to its destination, rather than to every computer on the network before the destination machine receives it.

local area network (LAN)

A type of network where computers are close together, typically in the same building or office.

wide area network (WAN)

A type of network where the computers are far apart—in different buildings, different cities, or even different countries.

node

Any sending and receiving point in a computer network.

fiber-optic cable

Cable that uses light guided through thin glass tubes, instead of electrical signals, to transmit data. It is very fast but also expensive.

wireless communication

Data transmission that uses radio frequencies instead of cabling. Wi-Fi is a version of this

bridge

Often called a network switch, this connects many parts of a network and directs traffic as needed.

backbone

The central core of a network, this connection can link many smaller networks to a larger network.

network architecture

The design of a computer network, which specifies how devices communicate with one another. The most common network architecture types are client/server and peer-to-peer.

twisted-pair cable

The most commonly used kind of networking cable today.

packet

The small unit into which information is broken down before being sent across a network.

topology

The study of how items are related to one another in space; a configuration.

network

Two or more devices connected together, along with the equipment used to connect them.

extranet

What an organization's intranet becomes when the organization allows outsiders to access its intranet.