07-12-2012, 02:33 PM
Networking
Computer-Networks--Network.ppt (Size: 838.5 KB / Downloads: 284)
Computer network A collection of computing devices that are connected in various ways in order to communicate and share resources
Usually, the connections between computers in a network are made using physical wires or cables
However, some connections are wireless, using radio waves or infrared signals
The generic term node or host refers to any device on a network
Data transfer rate The speed with which data is moved from one place on a network to another
Data transfer rate is a key issue in computer networks
Types of Networks
Local-area network (LAN) A network that connects a relatively small number of machines in a relatively close geographical area
Various configurations, called topologies, have been used to administer LANs
Ring topology A configuration that connects all nodes in a closed loop on which messages travel in one direction
Star topology A configuration that centers around one node to which all others are connected and through which all messages are sent
Bus topology All nodes are connected to a single communication line that carries messages in both directions
So, who owns the Internet?
Well, nobody does. No single person or company owns the Internet or even controls it entirely. As a wide-area network, it is made up of many smaller networks. These smaller networks are often owned and managed by a person or organization. The Internet, then, is really defined by how connections can be made between these networks.