Networking : Introduction

Networking is the concept of sharing resources and services. A network of computers is a group of interconnected systems sharing resources and interacting using a shared communications link. A network, therefore, is a set of interconnected systems with something to share. The shared resource can be data, a printer, a fax modem, or a service such as a database or an email system.

The individual systems must be connected through a pathway (called the transmission medium) that is used to transmit the resource or service between the computers. All systems on the pathway must follow a set of common communication rules for data to arrive at its intended destination and for the sending and receiving systems to understand each other. The rules governing computer communication are called protocols.

In summary, all networks must have the following:
1.A resource to share (resource)
2.A pathway to transfer data (transmission medium)
3.A set of rules governing how to communicate (protocols)

Having a transmission pathway does not always guarantee communication. When two entities communicate, they do not merely exchange information; rather, they must understand the information they receive from each other. The goal of computer networking, therefore, is not simply to exchange data but to understand and use data received from other entities on the network.
An analogy is people speaking, just because two people can speak, it does not mean they automatically can understand each other. These two people might speak different languages or interpret words differently. One person might use sign language, while the other uses spoken language. As in human communication, even though you have two entities who "speak," there is no guarantee they will be able to understand each other. Just because two computers are sharing resources, it does not necessarily mean they can communicate.

Because computers can be used in different ways and can be located at different distances from each other, enabling computers to communicate often can be a daunting task that draws on a wide variety of technologies.
The two main reasons for using computer networking are to provide services and to reduce equipment costs. Networks enable computers to share their resources by offering services to other computers and users on a network.

The following are specific reasons for networking PCs
1.Sharing files
2.Sharing printers and other devices
3.Enabling centralized administration and security of the resources within the system.
4.Supporting network applications such as electronic mail and database services
5.Limited resources
6.Desire to share the resources
7.Cost Reduction

Today, that's a limiting view, because the most important resource is information. Network lets us share information and Resource Sharing achieves the same

Resource Sharing

The purpose of many computer networks is to permit a far-flung community of users to share computer resources. Many such users now have their own microcomputers, so the shared resources have to be interesting enough to warrant access via a network. The facilities accessible by networks are in fact becoming more interesting at a rapid rate.
The remote computer may contain software that a user needs to employ. It may be proprietary software kept at one location. It may require a larger machine than any at the user's location. The distant computer may provide access to data that is stored and maintained at its location. Sometimes the remote machine controls a large or special printing facility. Sometimes the remote machine compiles programs that are used on smaller peripheral machines.

Cost Reduction
There are various aspects of technology that are likely to force the price of terminal usage drastically lower. This is important because almost all aspects of telecommunications are characterized by high price elasticity. In other words, when the price comes down, the usage goes up.


1)Computer Networks By Andrew S. Tanenbaum.
2)Computer Networks By William Stalling.
3)Wireless Communication & Networking By William Stalling.
4)CCNA Study Guide By BPB Publications.

No comments:

Post a Comment