Appendix b networks and telecommunications

telecommunication system

Enables the transmission of data over public or private networks.

network

A communications system created by linking two or more devices and establishing a standard methodology in which they can communicate.

local area network (LAN)

Connects a group of computers in proximity, such as in an office building, school, or home.

wide area network (WAN)

Spans a large geographic area such as a state, province, or country.

metropolitan area network (MAN)

A large computer network usually spanning a city.

LAN, WAN, and MAN

A network typically includes four things:

1. Protocol

2. Network Interface Card (NIC)

3. Cable

4. Hub (switch or router)

peer-to-peer (P2P) network

A computer network that relies on the computing power and bandwidth of the participants in the network rather than on a centralized server.

Peer to peer networks

client

A computer designed to request information from a server.

server

A computer dedicated to providing information in response to requests.

client/server network

A model for applications in which the bulk of the back-end processing, such as performing a physical search of a database, takes place on a server, whereas the front-end processing, which involves communicating with the users, is handled by the clients.

network operating system (NOS)

Operating system that runs a network, steering information between computers and managing security and users.

Client/server network

packet-switching

Occurs when the sending computer divides a message into a number of efficiently sized units of data called packets, each of which contains the address of the destination computer.

network topology

Refers to the geometric arrangement of the actual physical organization of the computers (and other network devices) in a network.

Network topologies

protocol

A standard that specifies the format of data, as well as the rules to be followed during transmission.

interoperability

The capability of two or more computer systems to share data and resources, even though they are made by different manufacturers.

ethernet

A physical and data layer technology for LAN networking.

Ethernet protocols

transmission control protocol/Internet protocol (TCP/IP)

Provides the technical foundation for the public Internet, as well as for large numbers of private networks.

TCP/IP four layer reference model

Internet protocol version 6 (IPv6)

The next-generation protocol, designed to replace the current version Internet protocol, IP version 4 (IPv4).

network transmission media

Refers to the various types of media used to carry the signal between computers.

wire media

Transmission material manufactured so that signals will be confined to a narrow path and will behave predictably.

Twisted pair, coaxial, and fiber-optic cable

twisted-pair cable

Refers to a type of cable composed of four (or more) copper wires twisted around each other within a plastic sheath.

coaxial cable

Cable that can carry a wide range of frequencies with low signal loss.

fiber optic (or optical fiber)

Refers to the technology associated with the transmission of information as light impulses along a glass wire or fiber.

wireless media

Natural parts of Earth’s environment that can be used as physical paths to carry electrical signals.

Communication satellite example