Fundamental Computer Networks Concepts

In the world of computers, networking is the practice of linking two or more computing devices together for the purpose of sharing data. Networks are built with a combination of computer hardware and computer software.

Types of Computer Networks

Networks can be categorized in several different ways. One method defines the type of a network according to the geographic area it spans. Alternatively, networks can also be classified based on topology or on the types of protocols they support.

One way to categorize the different types of computer network designs is by their scope or scale. For historical reasons, the networking industry refers to nearly every type of design as some kind of area network. Common examples of area network types are:

• LAN - Local Area Network
• WLAN - Wireless Local Area Network
• WAN - Wide Area Network
• MAN - Metropolitan Area Network
• SAN - Storage Area Network, System Area Network, Server Area Network, or sometimes Small Area Network
• CAN - Campus Area Network, Controller Area Network, or sometimes Cluster Area Network
• PAN - Personal Area Network
• DAN - Desk Area Network

The building blocks of a home computer network include adapters, routers and/or access points. Wired (and hybrid wired/wireless) networking also involves cables of varying types. Finally, large-scale enterprise networks in particular often employ other advanced equipment for specialized communication purposes.

Ethernet is a physical and data link layer technology for local area networks. Homes, schools and offices around the world all commonly use Ethernet standard cables and adapters to network personal computers.

Wi-Fi is the most popular wireless communication protocol for local area networks. Private home and business networks, and public hotspots, use Wi-Fi to networks computers and other wireless devices to each other and the Internet. Bluetooth is another wireless protocol commonly used in cellular phones and computer peripherals for short range network communication.

The technologies used to connect to the Internet are different than those used for connecting devices on local area network. DSL, cable modem and fiber provide fixed broadband Internet service, while WiMax and LTE additionally support mobile connectivity. In geographic areas where these high-speed options are unavailable, subscribers are forced to use older cellular services, satellite or even dial-up Internet instead.

Network Design

Computer networks also differ in their design. The two types of high-level network design are called client-server and peer-to-peer. Client-server networks feature centralized server computers that store email, Web pages, files and or applications. On a peer-to-peer network, conversely, all computers tend to support the same functions. Client-server networks are much more common in business and peer-to-peer networks much more common in homes.

A network topology represents its layout or structure from the point of view of data flow. In so-called bus networks, for example, all of the computers share and communicate across one common conduit, whereas in a star network, all data flows through one centralized device. Common types of network topologies include bus, star, ring and mesh.

Network Protocols

In networking, the communication language used by computer devices is called the protocol. Yet another way to classify computer networks is by the set of protocols they support. Networks often implement multiple protocols to support specific applications. Popular protocols include TCP/IP, the most common protocol found on the Internet and in home networks.