INTERNET BASICS:

NETWORKING:

In past, the computers were stand-alone systems, and transferring information from one computer to another required a tape or a disk. Resources (like CD-ROM drive, floppy drive etc.) and peripherals (like printers, scanners, plotters, etc.) of any computer could not be shared by other computers. Networking – or interconnecting the computers – was a solution for this. A network is simply the most cost-effective way to share equipment such as computers, printers and scanners that have been connected by cables. A network helps people work collectively.

A network can be as simple as connecting two computers. A large network can link hundreds or thousands of computers and peripherals in various configurations. Computer networks are available in different types.

Local Area Network (LAN)

A LAN connects network devices over a relatively short distance. An office building or school usually contains a LAN.

Wide Area Network (WAN)

A WAN spans a large physical distance. A WAN like the Internet spans most of the world!

Intranet

It is a network of computers within an enterprise that can share data using existing standardized www protocols.

INTERNET

Internet is a “network of networks” that links computers around the world. It allows communication across networks, i.e. one can communicate between one network and another network. This allows people to have access to information from different websites, locations or machines. It literally puts a world of information and a potential worldwide audience at your fingertips.

IMPORTANT FEATURES

Some of the facilities available on the Internet are:

• World Wide Web

The Internet application that is currently drawing the most attention is the World Wide Web. It has dramatically influenced the online world and continues to grow in popularity.

• Direct Communication

Through email (electronic mail), messages can be sent to or received from any part of the world within a few minutes.

• Round-The-Clock Availability

Information on the Internet is available to the users 24 hours a day

• Central Repository of Data

The Internet is like a huge central warehouse of data that can be accessed by people from all over the world.

• Search Engines

They are like dictionaries which help you get any information from all over the world within few minutes

• Advertisement

A company can advertise its products/services

• E-Commerce

The Internet is increasingly being used for carrying out money transactions. Through the Internet you can shop and pay through your credit card or ask your bank to transfer your money to a different account, without even leaving your desk.

• Distance Learning

Several online distance learning courses are offered by Indian and foreign universities on the Internet.

• BBS and New Services

The Internet is perhaps the cheapest medium for online help. BBS Services are available on the Net through which you can ask questions and get immediate troubleshooting assistance.

• Wide Area Networks

Using the Internet, organization can collect and compile information from offices spread over a large geographical area.

• Shareware Software

Internet is also a great medium for downloading free software. You can get free games, utilities and trial versions of softwares through the Net.

PREREQUISITIES FOR INTERNET

Hardware

1. A computer with serial port for connecting external modem or a spare expansion slot for connecting an internal modem card.
2. A modem (internal or external), ideally a faster one (with a speed of 56 KBPS [Kilo Bytes Per Second] or more) is required. A modem converts electronic signals from your computer into analog signals (sound), which can then be sent over the telephone lines.
3. Cables with jacks and sockets to connect your modem with the computer and telephone.

Software

1. Windows – although you can use earlier versions, Windows 98 or higher version is preferable because it has inbuilt components to support Internet connectivity.
2. A web browser such as Internet Explorer or Netscape Navigator. A browser is a client software program that allows the user to navigate the web.

Others

1. A telephone connection
2. An Internet account. If you want to have Internet access at your home, you will need to sign on with an Internet Service Provider (ISP). Some common ISPs are MTNL and VSNL.

FACTORS AFFECTING THE SPEED OF INTERNET CONNECTIVITY

1. 1. Speed of the modem A modem with a minimum speed of 56kbps or higher is recommended.
2. 2. Quality of phone line Noise on the phone line running into your home can disrupt Internet connection with a modem.
3. 3. Internet traffic Web traffic tends to expand throughout the day and peaks around the early evening. If you plan to download software or wish to surf faster, schedule such activities during off-peak hours.

There are factor associated with your computer.

• A faster processor (650 MHz or higher) will allow you to surf the Web faster.
• A computer with more memory (Random Access Memory) will help t surf faster. One way to avoid slowdowns is to avoid working with other software applications while you are surfing.
• A highly fragmented hard disk can slow down Web surfing considerably. It is good practice to keep your hard drive defragmented and optimized.
• Your Web browser’s Cache is a storage area on your computer’s hard disk. As you surf, the browser stores the Web pages you visit in the cache upto the disk space limit that you have set. The browser can display cached Web pages faster since they may be retrieved from the hard disk and not from the Internet. You might want to increase your browser’s cache limit.
• To further increase your surfing speed you can surf with two or more browser windows at a time. This will enable you to read the contents of one page while allowing the other page to load in the second window. This may help to cut down the “lag time” and frustration. You may also consider turning off image loading and Java in your browser (go to Advanced tab of Internet Options in the Tools menu). This may not affect the content of the web page.

INTERNTET PROTOCOLS

People very often forget the basic protocols of network. Before we understand the internet protocols, let’s first discuss addresses. The Internet has large number of computers connected to it, from which arises the need of proper addressing system. Each computer on the network is called a host, and has a name and a number that identifies it.

IP ADDRESS

Internet Protocol (IP) address is the numeric location of your computer so that it is an identifiable machine to all the other computers connected to the Internet. The IP address is a 32-bit number divided into four octets, and these octets are written in dotted-decimal format, e.g. 11.245.196.212.