Networking

Definition of a network

A computer network often simply referred to as a network, is a collection of computers and devices interconnected by communications channels that facilitate communications among users and allow users to share resources. Computer Networking is when two or more computers communicate directly or exchange information.

Categories of networks

• Wide Area Networks (WAN)
• Local Area Network (LAN)
• Metropolitan Area Network (MAN)

Wide Area Network (WAN)

A WAN system has the ability to link computers throughout a country or even across multiple countries. A good example of a WAN network is the internet.

Types of WAN

• Centralized: A centralized WAN has one mainframe or another "smart" computer as its core unit. It serves terminals at remote locations.
• Distributed: A Distributed network uses more than one smart computer as its core unit, and each of these can equally transmit and control data.

Types of networks

• Arcnet
• Token ring
• Ethernet

Network topology

In computer networking, topology refers to the layout of connected devices.

Types of topology

• Ring topology: In a ring network, the computers are connected in a loop. They address each other by putting a "message" (data or request for information, for example) on the loop. The message goes around the ring to each computer in turn. Only the computer to whom it is addressed will respond to it.
• Star topology: A star topology connects each computer to a central node. This is usually a computer that controls the network. Each computer sends messages to the others only through the central node.
• Bus topology: In a bus topology, the computers are hooked together along a connection cable. However, the ends of the connecting cable are not hooked together as they are in a ring. A message is sent to all computers at once. Only the one to whom it is addressed responds.