An Overview of Computer Networking
Typically a network is a collection of devices that are communicating which each other. Thecommunicating devices do not necessarily have to be computers only. The activity of communicating or conveying information between different computers or similar computing systems relies heavily on the science of computer networking. Many fields of study make use of this intelligent and advanced branch of computer engineering. It encompasses many mother fields that are concerned with the technology of electronic communication.
This linking employs the use of a variety of communication media depending on their inherent properties and characteristics and also the purpose and the type of communication for which they are being employed. These media maybe classified as guided media or unguided media.
A guided medium constitutes of elements which allow signals to be passed through a physical medium. Some commonly used examples are co-axial cables, twisted pair copper wire cables and optical fibers. An unguided medium on the other hand does not have a physical path for the signal is most often termed as the wireless media.
For networks which boast a higher data rate, co-axial cables are used. This medium provides a better speed than the twisted pair copper cable and hence can span longer distances at higher speeds. However, as electric signals are prone to die out with time, the use of fiber optics as a network communication medium is highly gaining popularity. As these work on the principle of total internal reflection of light, there is minimum data loss. Also since light travels at a very high speed, the rate of data transmission is very high.
Wireless media makes use of radio waves and light waves to achieve communication between various networks and have their own advantages and disadvantages.
Internet, intranet and extranet are the three major types of networks according to which various communication and computing systems may be linked together for exchange of data, information or resources. Intranet and extranet may be parts of a LAN (local area network). The internet however, is a vast assemblage of different networks that work on certain specific common protocols to provide certain common services. The internet is not controlled by any one person or organization or institute and is most commonly referred to as the World Wide Web.
An inter-network, also shortened as internet, is the communication or connection across multiple networks. It is worth mentioning that all the individual systems in a single network work and operate under the same policies, administration and protocols. It is practically impossible for one part of a network to work on and utilize one technology and the other part to operate on another technology. In other words, these are the criteria that determine which computer belongs to a particular network. An inter-network hence, allows variation of protocols and technologies area wise and so on.
Internet, Intranet and extranet all work on the TCP/IP protocol. An intranet is a restricted or private computer network, usually owned by a particular organization or enterprise. When the intranet is extended for use to authorized external users, such as customers or business partners then it is termed as the extranet.