Structure and Nature of Internet- An IntroductionInformation and communication are the major sources for the development of a society oran individual. Faster means of communication and information transfer are availabletoday.Think out the ways you generally use:•Oral- Example: Talk to a friend•Written- Example: Write a letter•Digital- Example: Send an SMSWhat would you do in the following situation?Your manager has been to Delhi to attend an important meeting and he asks you to sendsome files immediately. How would you send them at an earliest? Yes, the most possible solution today is using the Internet.
Structure and Nature of Internet- What is Internet?The Internet is a large network of systems interconnected with each other. Internet offersa variety of services and tools.Today, people across the world interchange lot of information called ‘data’ using theInternet. The most common uses of the Internet are sending and receiving e-mails,chatting, searching for information, etc.Terms you should know: Intranet: Extranet: An Intranet is the private networking An Extranet is actually an Intranet system within an organization. You that is partially accessible to can simply define it as a private authorized outsiders. Simply, it is an internet. Intranet serves as powerful extended Intranet to the users tool of communication in an outside an organization. People who organization. are not related to the organization cannot access the information.
Modem stands for MOdulator/DEModulator. Structure and Nature of Internet- Connection Requirements The basic requirements to get an Internet connection are: • Modem stands for •a computer MOdulator/DEModulator. A modem is a device that • a phone-line enables a computer to transmit data over phone or cable • a modem • ISP stands for Internet Service • an ISP Provider. An ISP can be company offering its clients to access the Internet. There are different types of internet connections available today. The requirements to connect to the Internet change based on the type of connection you choose.
Structure and Nature of Internet- Connection Requirements Continued…Following are some common types of Internetconnections:Dial-up: The ‘Dial-up’ connection is mostly preferred for domestic purposes.Requirements: a phone-line, modem, and an Internet Service Provider (ISP). Thetypical Dial-up connection speeds range from 2400 bps to 56 Kbps.Cable: Through the use of a cable modem you can have a broadband Internetconnection that is designed to operate over cable TV lines. The cable connectionspeeds range from 512 Kbps to 20 Mbps. Wireless: Wireless Internet, or wireless broadband is one of the newest Internet connection types. Instead of using telephone or cable networks for your Internet connection, you use radio frequency bands. The wireless speeds range from 1.6 Mb/s 66 GHz.Generally, we choose the type of connection based on our domestic or businessrequirements.
Structure and Nature of Internet- How do computers talk to each other?Answer the following:Who brings you the letters?How do they reach you instead of going to someone else? You are right! A postman brings them to you based on the door number in the address.Similarly, your computer requires a Gateway which brings you the information based on theInternet Protocol address of your computer. Gateway IP Address A gateway is a node (a router) Each computer (known as a on a computer network that host) on the Internet has at serves as an access point to least one IP address that another network. This node is uniquely identifies it from all capable of sending, receiving, other computers on the or forwarding information over Internet. a communications channel.
Structure and Nature of Internet- How can a computer use the telephone line?If you have a telephone-line, you can access tothe Internet through a ‘Dial-up’ connection. What if I don’t have a computer?Using a modem connected to your PC, usersconnect to the Internet when the computer dials a Advancement in technology has made access to internet evenphone number (which is provided by your ISP) much easier. You can getand connects to the network. In ‘Dial-up’ connected to the Internet if yourconnections, data is sent over public telephone mobile has the GPRS (Generalnetwork. Packet Radio Service) option. Your mobile acts as a miniThe modem converts the data to digital and vise computer.versa. However, dial-up connection is slow as ituses the normal telephone lines. Also the datarates are limited.
How is a computer address different from a phone number when their purpose is the same?You talk to a person using a phone.But using a ‘Dial-up’ connection, youstart interacting with another computerusing your computer.Also the format of a phone number andan IP address vary.The format of an IP address is a 32-bitnumeric address written as fournumbers separated by periods. Eachnumber can be zero to 255. Forexample, 192.168.1.28 could be an IPaddress.
How do I get an address for my computer and start working on the computer?You can contact your ISP once you have all the requirements in place.Your ISP provides you the basic information for accessing the Internet such as theGateway and IP address allotted to your computer.If you want to connect to the Internet, you have to do the following: • Configure a Dial-up Networking (DUN) • Dial your Point of Presence (POP) • Log into your Internet Service Provider (ISP)
Using Internet- The World Wide WebIn the previous section, you have learnt aboutthe different Internet connection types andtheir requirements. In this section, you willlearn about the basics and the effective waysof using the Internet.Do you know what is WWW? Yes, WWW is the short form of the World Wide Web. In short we call it the Web.Tim Berners-Lee, a scientist at CERN, inventedthe World Wide Web (WWW) in 1990. Thebasic idea of the WWW was to merge thecomplex Internet technologies into easy to useglobal information system.
Using Internet- Web BrowsersA web browser or browser is a software application that helps you to browse or locate anddisplay the Web pages. These Web pages may contain text, images, music, videos,games, etc.The most common Web browsers are: Internet Explorer Mozilla Firefox Google Chrome Safari Opera Netscape
Using Internet- Web Browsers Continued…You can install these software applications on your computer system. After the installation iscomplete, you can find a small browser icon on your desktop. Next time when you want toopen the browser, you can simply click on the icon.Following is an image of a Web browser window:
Using Internet- Navigating Across the Web PagesYou have already learnt that a browser helps you to locate the Web pages. Let’s have aglance of the main features of a browser window that help you to locate as well asnavigate across the Web pages. Type the URL of a website in the address bar and press Enter. Navigation and Reload Buttons The Status bar displays the status of the page being loaded. The Menu bar options help you work with different setting options.
Using Internet- Opening Web pages using URLsRecall when you first visited your friend’s house. You could easily locate his house with thehelp of the address.Similarly, you need to provide the URL (Uniform Resource Locator) of a website in thebrowser’s address bar.Example of a URL:Understanding the URL: • http stands for Hypertext Transfer protocol which is a request/response between an end user (you) and the server (Web site). http remains common for most of the websites. URLs that start with https denote to be a secure website. • google.co.in stands for the domain name. This name is followed by a slash (/) if you intend to open a page within the domain name. So you need to have a proper URL of a Web site to open it in a browser.
Using Internet- Opening linked pagesHow do you open a specific chapter in atext book? Yes, you can find a list of chapters and their page numbers on the Index page.A website also has several pages. And it’svery easy to open the pages you want tosee when compared to a text book.Let’s see how:Observe the text on a Web page. Somewords are underlined in color. Some wordsor images change their colors when youmove the mouse over them. The cursor alsochanges to a pointer icon. Such words orimages are linked to the pages which havethe information related to them.These words or images, called Hyperlinks,make navigation across the pages of a Website easy.
Searching- Search EnginesWe search for something when we don’t know its exact location. Likewise, if youdon’t know the URL of a specific Web site, you have to search for it. You cannot usea browser’s address bar to search for the information or a Web site.Then, how do I search for any information? There are tools called Search Engines which help you to locate the information you want.Following is an image of some common types of search engines: