142 Chapter 5

hub

A basic network device that provides multiple ports for connecting nodes.

coaxial cable

A cable that consists of a single copper wire that is surrounded by insulation and a wire mesh shield.

twisted-pair cable

A cable that consists of four pairs of wires that are twisted around each other. Each copper wire is insulated in plastic, and all wires are collectively bound together in a layer of plastic.

Router

A complex device that stores the routing information for networks. It looks at each packet's header to determine where the packet should go, then determines the best route for the packet to take toward its destination.

Information System

A complex system for acquiring, storing, organizing, using, and sharing data and information.

Network Interface Card (NIC)

A computer component that translates and transmits network packets.

Local Area Network (LAN)

A data communication system consisting of multiple devices that are relatively near each other and are connected using cables or wireless media.

bridge

A device that connects two lans or two segments of the same lan; looks at the information in each packet header and forwards data traveling from one lan to another.

Social Engineering

A form of hacking that focuses on deceiving individuals into giving away the information that the thief needs.

Business Intelligence (BI)

A framework that encompasses all of the data, tools, and strategies used by businesses to improve decision making and make predictions.

fiber-optic cable

A high-speed cable that consists of a thin strand of glass that transmits pulsating beams of light rather than electric current.

switch

A network device that is similar to a hub, but it is aware of the exact address or identity of all the nodes attached to it, thereby increasing the efficiency of the network.

Repeater

A network device used to prevent attenuation when packets are traveling long distances.

gateway

A node on a network that serves as a portal to other networks.

Extranet

A service that allows organizations to share some of its intranet resources with people outside the organization.

Decision Support System (DSS)

A special application that collects and reports certain types of data, thus helping managers make better decisions.

Raid

A storage system that links any number of disk drives (a disk array) so that they act as a single disk.

Virtual Private Network (VPN)

A type of connection that increases the security of network communication by employing a method called "tunneling", whereby each packet from the sending computer is encapsulated within another packet.

Office automation system

A type of information system that is designed to manage information in an office environment and help users handle certain information-related tasks more efficiently.

Expert System

A type of information system that performs analytical tasks traditionally done by a human, using sequences of questions to ask and actions to take based on the responses to those questions.

worm

A type of malware that self-replicates and spreads through computers and networks without the need to attach to a host file.

MAC address

A unique identifier contained in the network interface hardware of computers and other network-connected devices.

rogue hotspot

A wireless access point set up by a hacker in a public area to intercept users' communication.

Zombies

An infected and compromised computer that is under the external control of a hacker, usually without the knowledge of the computer's owner.

Intranet

An internal version of the Internet containing information that is restricted to a particular company's employees

Wireless Access Point (WAP)

Connects single or multiple PCs in the wireless environment.

Pretexting

Gaining someone's trust by pretending you are someone else.

Bandwidth

In networks, it refers to the amount of data that can be transmitted over a given amount of time.

Interoperability

The ability of each organization's information system to work with the other, sharing data and services.

Wide Area Network (WAN)

The connection of two or more central computers or LANs, generally across a wide geographical area.

Topology

The logical layout of the cables and devices that connect the nodes of the network.

Attenuation

The loss of intensity and clarity of a transmitted data signal

Network Media

The means used to link parts of a computer network.

Ethernet

The most common physical standard for local area networks.

Packets

pieces of a message broken down into small units by the sending device and reassembled by the receiving device