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February 10, 2018 | Author: Anonymous | Category: Documents
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The Web is a service (a system for accessing documents) that is supported by the ... landline broadband (over coaxial ca...

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Presented by: Tejas. B. Prajapati (MMS-II)-Systems CREATION / HISTORY OF THE INTERNET

The word Internet has been coined from the words, ‘ Interconnections’ and ‘Networks’. The Internet was born in 1969, out of efforts to connect together a US Defence Department network called the ARPAnet (Advanced Research Projects Agency Network) and various other radio and satellite networks. In order to share information, researchers and scientists from universities and research laboratories developed the interconnection of their computers and over time, the internet has become a global resource. The internet has grown explosively in the 1990’s. It is composed of over 30,000 connected networks from more than 100 countries. Today the internet as become a information superhighway consisting of billions of people connected to each other. As of January 11, 2007, 1.093 billion people use the Internet according to Internet World Stats. BASICS OF THE INTERNET

The Internet is the worldwide, publicly accessible, network of interconnected computer networks that transmit data by packet switching using the standard Internet Protocol (IP). It is a "network of networks" that consists of millions of smaller domestic, academic, business, and government networks, which together carry various information and services, such as electronic mail, online chat, file transfer, and the interlinked Web pages and other documents of the World Wide Web.

TERMINOLOGY: INTERNET VS. WEB

The Internet and the World Wide Web are not synonymous. The Internet is a collection of interconnected computer networks, linked by copper wires, fiber-optic cables, wireless connections, etc. The Web is a collection of interconnected documents and other resources, linked by hyperlinks and URLs.

Many people believe that the Web and the Internet are the same thing, but this is not correct. In fact, they are two different things. The Web is a service (a system for accessing documents) that is supported by the Internet (a gigantic network). The World Wide Web is accessible via the Internet, as are many other services including e-mail, file sharing etc.

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Presented by: Tejas. B. Prajapati (MMS-II)-Systems INTERNET STRUCTURE

There have been many analyses of the Internet and its structure. In network schematic diagrams, the Internet is often represented by a cloud symbol, into and out of which network communications can pass.

INTERNET PROTOCOLS

Protocols are the rules that govern data and its communication. They allow cooperating computers to share or understand each other across a network. There are three layers of protocols: At the lowest level is IP (Internet Protocol), which defines the data-grams or packets that carry blocks of data from one node to another. The vast majority of today's Internet uses version four of the IP protocol (i.e. IPv4), and although IPv6 is standardized, it exists only as "islands" of  connectivity, and there are many ISPs who don't have any IPv6 connectivity at all. 





Next come TCP (Transmission Control Protocol) and UDP (User Datagram Protocol) - the protocols by which one host sends data to another. The former makes a virtual 'connection', which gives some level of  guarantee of reliability. The latter is a best-effort, connectionless transport, in which data packets that are lost in transit will not be re-sent. On top comes the Application protocol. This defines the specific messages and data formats sent and understood by the applications running at each end of the communication. Ex: HTTP (Hypertext transfer protocol), FTP(File Transfer Protocol), SMTP(Simple Mail Transfer Protocol).

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Presented by: Tejas. B. Prajapati (MMS-II)-Systems

ICANN The Internet Corporation for Assigned Names and Numbers (ICANN) is the authority that coordinates the assignment of unique identifiers on the Internet, including domain names, Internet protocol addresses, and protocol port. A globally unified namespace (i.e., a system of names in which there is one and only one holder of each name) is essential for the Internet to function. Because the Internet is a distributed network comprising many voluntarily interconnected networks, the Internet, as such, has no governing body. ICANN's role in coordinating the assignment of unique identifiers distinguishes it as perhaps the only central coordinating body on the global Internet.

LANGUAGE

The most prevalent language for communication on the Internet is English. The Internet's technologies have developed enough in recent years that good facilities are available for development and communication in most widely used languages like Deutsch, Hindi, Italiano, Marathi to name a few. HOW THE WEB WORKS

Web documents can be linked together because they are created in a format known as hypertext. Hypertext systems provide an easy way to manage large collections of data, which can include text files, pictures, sounds, movies, and more. To support hypertext documents, the Web uses a special protocol, called the hypertext transfer protocol, or HTTP. A hypertext document is a specially encoded file that uses the hypertext markup language, or HTML. This language allows a document’s author to embed hypertext links—also called hyperlinks or just links—in the document. HTTP and hypertext links are the foundations of the World Wide Web. As you read a hypertext document—more commonly called a Web page—on screen, you can click a word or a picture encoded as a hypertext link and immediately jumps to another location within the same document or to a different Web page. The second page may be located on the same computer as the original page, or anywhere else on the Internet. A collection of related Web pages is called a Web site. Web sites are housed on Web servers, Internet host computers that often store thousands of individual pages. Copying a page onto a server is called publishing the page, but the process also is called posting or uploading. Web pages are used to distribute news, interactive educational services, product information, catalogs, highway traffic reports, and live audio and video, among many others.

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Presented by: Tejas. B. Prajapati (MMS-II)-Systems

How to access the Internet The Internet is a gigantic collection of millions of computers, all linked together on a computer network. The network allows all of the computers to communicate with one another. A home computer may be linked to the Internet using a phone-line modem, modem, DSL or cable modem that talks to an Internet service provider ( ISP). A computer in a business or university will usually have a network interface card ( NIC) that directly connects it to a local area network ( network (LAN) inside the business. The business can then connect its LAN to an ISP using a high-speed phone line like a T1 line. A T1 line can handle approximately 1.5 million bits per second, while a normal phone line using a modem can typically handle 30,000 to 50,000 bits per second. ISPs then connect to larger ISPs, and the largest ISPs maintain fiber-optic "backbones" for an entire nation or region. Backbones around the world are connected through fiberoptic lines, undersea cables or satellite links (see An Atlas of Cyberspaces for some interesting backbone maps). In this way, every computer on the Internet is connected to every other computer on the Internet.

Common methods of home access include dial-up, landline broadband (over coaxial cable, fibre optic or copper wires), Wi-Fi, satellite and cell phones. Public places to use the Internet include libraries and Internet cafes, where computers with Internet connections are available. There are also Internet access points in many

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Presented by: Tejas. B. Prajapati (MMS-II)-Systems public places such as airport halls and coffee shops, in some cases just for brief use while standing. Wi-Fi provides wireless access to computer networks, and therefore can do so to the Internet itself. Hotspots providing such access include Wi-Fi-cafes, where a would-be user needs to bring their own wireless-enabled devices such as a laptop or PDA. These services may be free to all, free to customers only, or fee-based. A hotspot need not be limited to a confined location. The whole campus or park, or even the entire city can be enabled. High-end mobile phones such as smartphones generally come with Internet access through the phone network. Web browsers such as Opera are available on these advanced handsets, which can also run a wide variety of other Internet software.

Clients and Servers In general, all of the machines on the Internet can be categorized as two types: servers and clients. Those machines that provide services (like Web servers or FTP servers) to other machines are servers. And the machines that are used to connect to those services are clients. When you connect to Yahoo! at www.yahoo.com to read a page, Yahoo! is providing a machine (probably a cluster of very large machines), for use on the Internet, to service your request. Yahoo! is providing a server. Your machine, on the other hand, is probably providing no services to anyone else on the Internet. Therefore, it is a user machine, also known as a client. A server machine may provide one or more services on the Internet. For example, a server machine might have software running on it that allows it to act as a Web server, an e-mail server and an FTP server. Clients direct their requests to a specific software server running on the overall server machine. For example, if you are running a Web browser on your machine, it will most likely want to talk to the Web server on the server machine. Your Telnet application will want to talk to the Telnet server, your e-mail application will talk to the e-mail server, and so on...

IP Addresses To keep all of these machines straight, each machine on the Internet is assigned a unique address called an IP address. IP stands for Internet protocol, and these addresses are 32-bit numbers, numbers , normally expressed as four "octets" in a "dotted decimal number." A typical IP address looks like this: 216.27.61.137

The four numbers in an IP address are called octets because they can have values between 0 and 255, which is 2 8 possibilities per octet. Every machine on the Internet has a unique IP address. A server has a static IP address that does not change very often. A home machine that is dialing up through a modem often has an IP address that is assigned by the ISP when the machine dials in. That IP 5

Presented by: Tejas. B. Prajapati (MMS-II)-Systems address is unique for that session -- it may be different the next time the machine dials in. This way, an ISP only needs one IP address for each modem it supports, rather than for each customer. WEB BROWSERS

For several years, the Web remained an interesting but not particularly exciting tool used by scientific researchers. But in 1993, developers at the National Center for Supercomputing Applications (NCSA) created Mosaic, a point-and-click Web browser. A Web browser (or browser) is a software application designed to find hypertext documents on the Web and then open the documents on the user’s computer. A point-and-click browser provides a graphical user interface that enables the user to click  hyperlinked text and images to jump to other documents or view other data. Several textbased Web browsers are also available and are used in non-graphical operating systems, such as certain versions of UNIX. Mosaic and Web browsers that evolved from it have changed the way people use the Internet. Today, the most popular graphical Web browsers are Microsoft’s Internet Explorer and Mozilla Firefox. URLs

The hypertext transfer protocol uses Internet addresses in a special format, called a Uniform Resource Locator, or URL. URLs look like this: type://address/path

In a URL, type specifies the type of server in which the file is located, address is the address of the server, and path is the location within the file structure of the server. The path includes the list of folders where the desired file (the Web page itself or some other piece of data) is located. Consider the URL for a page at the Library of Congress Web site, which contains information about the Library’s collection of permanent.

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WHAT IS A WEB SERVER

Have you ever wondered about the mechanisms that delivered this page to you? when you clicked on the link for this page, or typed in its URL (uniform resource locator), what happened behind the scenes to bring this page onto your screen? Let's say that you are sitting at your computer, surfing the Web, and you get a call from a friend who says, "I just read a great article! Type in this URL and check it out. It's at http://www.howstuffworks.com/web-server.htm." So you type that URL into your browser and press return. And magically, no matter where in the world that URL lives, the page pops up on your screen. At the most basic level possible, the following diagram shows the steps that brought that page to your screen:

Your browser formed a connection to a Web server, requested a page and received it.

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Presented by: Tejas. B. Prajapati (MMS-II)-Systems Behind the Scenes

* The browser broke the URL into three parts: 1. The protocol ("http") 2. The server name ("www.howstuffworks.com") 3. The file name ("web-server.htm") * The browser communicated with a name server to translate the server name "www.howstuffworks.com" into an IP Address, which it uses to connect to the server machine. * The browser then formed a connection to the server at that IP address on port 80. * Following the HTTP protocol, the browser sent a GET request to the server, asking for the file "http://www.howstuffworks.com/web-server.htm." (Note that cookies may be sent from browser to server with the GET request -- see How Internet Cookies Work for details.) * The server then sent the HTML text for the Web page to the browser. (Cookies may also be sent from server to browser in the header for the page.) * The browser read the HTML tags and formatted the page onto your screen. WHAT IS A DNS SERVER Domain Names

Because most people have trouble remembering the strings of numbers that make up IP addresses, and because IP addresses sometimes need to change, all servers on the Internet also have human-readable names, called domain names. For example, www.howstuffworks.com is a permanent, human-readable name. It is easier for most of  us to remember www.howstuffworks.com than it is to remember 209.116.69.66. The name www.howstuffworks.com actually has three parts: 1. The host name ("www") 2. The domain name ("howstuffworks") 3. The top-level domain name ("com") VeriSign.. Domain names within the ".com" domain are managed by the registrar called VeriSign VeriSign also manages ".net" domain names. VeriSign creates the top-level domain names and guarantees that all names within a top-level domain are unique. The host name is created by the company hosting the domain. "www" is a very common host name, but many places now either omit it or replace it with a different host name that indicates a specific area of the site. For example, in encarta.msn.com encarta.msn.com,, the domain name for Microsoft's Encarta encyclopedia, "encarta" is designated as the host name instead of  "www."

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Name Servers

A set of servers called domain name servers (DNS) maps the human-readable names to the IP addresses. These servers are simple databases that map names to IP addresses, and they are distributed all over the Internet.

The whois Command On a UNIX machine, you can use the whois command to look up information about a domain name. You can do the same thing using the whois form at VeriSign.. If you type in a domain VeriSign name, like "howstuffworks.com," it will return to you the registration information for that domain, including its IP address.

If you type the URL "http://www.howstuffworks.com/web-server.htm" into your browser, your browser extracts the name "www.howstuffworks.com," passes it to a domain name server, and the domain name server returns the correct IP address for www.howstuffworks.com. A number of name servers may be involved to get the right IP address. Ports

Any server machine makes its services available to the Internet using numbered ports, one for each service that is available on the server. For example, if a server machine is running a Web server and an FTP server, the Web server would typically be available on port 80, and the FTP server would be available on port 21. Note that there is nothing that forces, for example, a Web server to be on port 80. If you were to set up your own machine and load Web server software on it, you could put the Web server on port 918, or any other unused port, if you wanted to. Then, if your machine were known as xxx.yyy.com, someone on the Internet could connect to your server with the URL http://xxx.yyy.com:918. The ":918" explicitly specifies the port number, and would have to be included for someone to reach your server. When no port is specified, the browser simply assumes that the server is using the well-known port 80. A Resolver looks up the information associated with nodes. A resolver knows how to communicate with name servers by sending DNS requests, and heeding DNS responses. Resolving usually entails iterating through several name servers to find the needed information. Some resolvers function simplistically and can only communicate with a single name server. These simple resolvers rely on a recursing name server to perform the work of  finding information for them.

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Presented by: Tejas. B. Prajapati (MMS-II)-Systems

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Presented by: Tejas. B. Prajapati (MMS-II)-Systems WHAT IS FTP

The FTP (File Transfer Protocol) utility program is commonly used for copying files to and from other computers. Most operating systems and communication programs now include some form of an FTP utility program, but the commands differ slightly between them. You can also perform FTP through a browser. For example, bring up Internet Explorer and type in ftp://[email protected]

If the remote machine has been reached successfully, FTP responds by asking for a loginname and password . When you enter your own loginname and password for the remote machine, it returns the prompt ftp>

and permits you access to your own home directory on the remote machine. You should be able to move around in your own directory and to copy files to and from your local machine using the FTP interface commands ? bye cd close delete get put

to request help or information about the FTP commands to exit the FTP environment (same as quit) to change directory on the remote machine to terminate a connection with another computer  to delete (remove) a file in the current remote directory to copy one file from the remote machine to the local machine to copy one file from the local machine to the remote machine

An example of a normal ftp operation with file uploading ftp nordsieck.cs.colorado.edu % Connected to nordsieck.cs.colorado.edu. 220 nordsieck FTP server (Version 5.53 Tue Aug 25 10:46:12 MDT 1992) ready.  Name (nordsieck.cs.colorado.edu:yourlogin): yourlogin 331 Password required for yourlogin. Password : 230 User yourlogin logged in. ftp> ftp> put tmul.out 200 PORT command successful. 150 Opening ASCII mode data connection for tmul.out. 226 Transfer complete. ftp> bye 221 Goodbye.

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Presented by: Tejas. B. Prajapati (MMS-II)-Systems COMMON USES / APPLICATION OF THE INTERNET

E-MAIL: The concept of sending electronic text messages between parties in a way analogous to mailing letters or memos predates the creation of the Internet. Every day, the citizens of the Internet send each other billions of e-mail messages. e-mail has become an extremely popular communication tool. Have you ever wondered how e-mail gets from your desktop to a friend halfway around the world? An e-mail message has always been nothing more than a simple text message -- a piece of text sent to a recipient. In the beginning and even today, e-mail messages tend to be short pieces of text, although the ability to add attachments now makes many e-mail messages quite long. Even with attachments, however, e-mail messages continue to be text messages. E-mail Clients You have probably already received several e-mail messages today. To look at them, you use some sort of e-mail client. Many people use well-known stand-alone clients like Microsoft Outlook, Outlook Express, Eudora or Pegasus. People who subscribe to free email services like Hotmail or Yahoo use an e-mail client that appears in a Web page.

No matter which type of client you are using, it generally does four things: 

 



It shows you a list of all of the messages in your mailbox by displaying the message headers. The header shows you who sent the mail, the subject of the mail and may also show the time and date of the message and the message size. It lets you select a message header and read the body of the e-mail message. It lets you create new messages and send them. You type in the e-mail address of  the recipient and the subject for the message, and then type the body of the message. Most e-mail clients also let you add attachments to messages you send and save the attachments from messages you receive.

A Simple E-mail Server Given that you have an e-mail client on your machine, you are ready to send and receive e-mail. All that you need is an e-mail server for the client to connect to.

The simplest possible e-mail server would work something like this: 

It would have a list of e-mail accounts, with one account for each person who can receive e-mail on the server. My account name might be mbrain, John Smith's might be jsmith, and so on.

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It would have a text file for each account in the list. So the server would have a text file in its directory named MBRAIN.TXT, another named JSMITH.TXT, and so on. If someone wanted to send me a message, the person would compose a text message ("Marshall, Can we have lunch Monday? John") in an e-mail client, and indicate that the message should go to mbrain. When the person presses the Send button, the e-mail client would connect to the e-mail server and pass to the server the name of the recipient (mbrain), the name of the sender (jsmith) and the body of the message. The server would format those pieces of information and append them to the bottom of the MBRAIN.TXT file. The entry in the file might look like this:     

From: jsmith To: mbrain Marshall, Can we have lunch Monday? John

There are several other pieces of information that the server might save into the file, like the time and date of receipt and a subject line; but overall, you can see that this is an extremely simple process. As other people sent mail to mbrain, the server would simply append those messages to the bottom of the file in the order that they arrived. The text file would accumulate a series of five or 10 messages, and eventually I would log in to read them. When I wanted to look at my e-mail, my e-mail client would connect to the server machine. In the simplest possible system, it would: 1. 2. 3. 4. 5.

Ask the server to send a copy of the MBRAIN.TXT file Ask the server to erase and reset the MBRAIN.TXT file Save the MBRAIN.TXT file on my local machine Parse the file into the separate messages (using the word "From:" as the separator) Show me all of the message headers in a list

When I double-clicked on a message header, it would find that message in the text file and show me its body. This is a very simple system. Surprisingly, the real e-mail system that you use every day is not much more complicated than this. The Real E-mail System

For the vast majority of people right now, the real e-mail system consists of two different servers running on a server machine. One is called the SMTP server, where SMTP stands for Simple Mail Transfer Protocol. The SMTP server handles outgoing mail. The other is either a POP3 server or an IMAP server, both of which handle incoming mail. POP stands for Post Office Protocol, and IMAP stands for Internet Mail Access Protocol.

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A typical e-mail server looks like this:

The SMTP server listens on well-known port number 25, POP3 listens on port 110 and IMAP uses port 143

Let's assume that I want to send a piece of e-mail. My e-mail ID is brain, and I have my account account on o n howstuffworks.com. I want to send e-mail to  [email protected] I am using a stand-alone e-mail client like Outlook Express. When I set up my account at howstuffworks, I told Outlook Express the name of the mail server -- mail.howstuffworks.com. When I compose a message and press the Send button, here is what happens:

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Presented by: Tejas. B. Prajapati (MMS-II)-Systems 1. Outlook Express connects to the SMTP server at mail.howstuffworks.com using port 25. 2. Outlook Express has a conversation with the SMTP server, telling the SMTP server the address of the sender and the address of the recipient, as well as the body of the message. 3. The SMTP server takes the "to" address ([email protected]) and breaks it into two parts: The recipient name (jsmith) The domain name (mindspring.com)  

If the "to" address had been another user at howstuffworks.com, the SMTP server would simply hand the message to the POP3 server for howstuffworks.com (using a little program called the delivery agent). Since the recipient is at another domain, SMTP needs to communicate with that domain. 4. The SMTP server has a conversation with a Domain Name Server, or DNS (see How Web Servers Work for Work  for details). It says, "Can you give me the IP address of  the SMTP server for mindspring.com?" The DNS replies with the one or more IP addresses for the SMTP server(s) that Mindspring operates. 5. The SMTP server at howstuffworks.com connects with the SMTP server at Mindspring using port 25. It has the same simple text conversation that my e-mail client had with the SMTP server for HowStuffWorks, and gives the message to the Mindspring server. The Mindspring server recognizes that the domain name for jsmith is at Mindspring, so it hands the message to Mindspring's POP3 server, which puts the message in jsmith's mailbox. If, for some reason, the SMTP server at HowStuffWorks cannot connect with the SMTP server at Mindspring, then the message goes into a queue. The SMTP server on most machines uses a program called sendmail to do the actual sending, so this queue is called the sendmail queue. Sendmail will periodically try to resend the messages in its queue. For example, it might retry every 15 minutes. After four hours, it will usually send you a piece of mail that tells you there is some sort of problem. After five days, most sendmail configurations give up and return the mail to you undelivered.

THE WORLD WIDE WEB: (Access to information) Through keyword-driven Internet research using search engines, like Google, millions worldwide have easy, instant access to a vast and diverse amount of online information. Compared to encyclopedias and traditional libraries, the World Wide Web has enabled a sudden and extreme decentralization of information and data.

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REMOTE ACCESS The Internet allows computer users to connect to other computers and information stores easily, wherever they may be across the world. This is encouraging new ways of  working from home, collaboration and information sharing in many industries. For example: An accountant sitting at home can audit the books of a company based in another country, on a server situated in a third country that is remotely maintained by IT specialists in a fourth. These accounts could have been created by home-working bookkeepers, in other remote locations, based on information e-mailed to them from offices all over the world.

An office worker away from his desk, perhaps the other side of the world on a business trip or a holiday, can open a remote desktop session into his normal office PC using a secure Virtual Private Network (VPN) connection via the Internet. This gives him complete access to all his normal files and data, including e-mail and other applications, while he is away. COLLABORATION The low-cost and nearly instantaneous sharing of ideas, knowledge, and skills has made collaborative work dramatically easier. Not only can a group cheaply communicate and test, but the wide reach of the Internet allows such groups to easily form in the first place, even among niche interests. An example of this is the free software movement in software development which produced GNU and Linux from scratch and has taken over development of Mozilla and OpenOffice.org (formerly known as Netscape Communicator and StarOffice). Messages can be sent and viewed even more quickly and conveniently than via e-mail. Extension to these systems may allow files to be exchanged, 'whiteboard' drawings to be

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Presented by: Tejas. B. Prajapati (MMS-II)-Systems shared as well as voice and video contact between team members. Eg: Microsoft Net Meeting. FILE SHARING: A computer file can be e-mailed to customers, colleagues and friends as an attachment. It can be uploaded to a Web site or FTP server for easy download by others. It can be put into a "shared location" or onto a file server for instant use by colleagues.

These simple features of the Internet, over a world-wide basis, are changing the basis for the production, sale, and distribution of anything that can be reduced to a computer file for transmission. This includes all manner of office documents, publications, software products, music, photography, video, animations, graphics and the other arts. STREAMING MEDIA Many existing radio and television broadcasters provide Internet 'feeds' of their live audio and video streams (for example, the BBC). They may also allow time-shift viewing or listening such as Preview, Classic Clips and Listen Again features. These providers have been joined by a range of pure Internet 'broadcasters' who never had onair licenses. Podcasting is a variation on this theme, where—usually audio—material is first downloaded in full and then may be played back on a computer. Webcams can be seen as an even lower-budget extension of this phenomenon. Internet users can watch animals around an African waterhole, ships in the Panama Canal, the traffic at a local roundabout or their own premises, live and in real time. Video chat rooms, video conferencing, and remote controllable webcams are also popular. VOICE TELEPHONY (VOIP) VoIP stands for Voice over IP, where IP refers to the Internet Protocol that underlies all Internet communication. This phenomenon began as an optional two-way voice extension to some of the Instant Messaging systems that took off around the year 2000. In recent years many VoIP systems have become as easy to use and as convenient as a normal telephone. The benefit is that, as the Internet carries the actual voice traffic, VoIP can be free or cost much less than a normal telephone call, especially over long distances and especially for those with always-on ADSL or DSL Internet connections. Eg: Sify has started a business by which one can make ISD calls at a cheaper rate.

Thus VoIP is maturing into a viable alternative to traditional telephones. Interoperability between different providers has improved and the ability to call or receive a call from a traditional telephone is available. Simple inexpensive VoIP modems are now available that eliminate the need for a PC.Voice quality can still vary from call to call but is often equal to and can even exceed that of traditional calls. Eg Skype has the best voice quality as compared to any other VOIP clients. LEISURE: Today, many Internet forums have sections devoted to games and funny videos; short cartoons in the form of Flash movies are also popular. Over 6 million people use blogs or message boards as a means of communication and for the sharing of ideas.

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Presented by: Tejas. B. Prajapati (MMS-II)-Systems The pornography and gambling industries have both taken full advantage of the World Wide Web, and often provide a significant source of advertising revenue for other Web sites. Although many governments have attempted to put restrictions on both industries' use of the Internet, this has generally failed to stop their widespread popularity. One main area of leisure on the Internet is multiplayer gaming. This form of leisure creates communities, bringing people of all ages and origins to enjoy the fast-paced world of multiplayer games. These range from MMORPG to first-person shooters, from roleplaying games to online gambling. This has revolutionized the way many people interact and spend their free time on the Internet. Many use the Internet to access and download music, movies and other works for their enjoyment and relaxation. Many use the World Wide Web to access news, weather and sports reports, to plan and book holidays and to find out more about their random ideas and casual interests. People use chat, messaging and email to make and stay in touch with friends worldwide, sometimes in the same way as some previously had pen pals. Social networking Web sites like Friends Reunited and many others like them also put and keep people in contact for their enjoyment. MARKETING

The Internet has also become a large market for companies; some of the biggest companies today have grown by taking advantage of the efficient nature of  low-cost advertising and commerce through the Internet; also known as e-commerce. It is the fastest way to spread information to a vast amount of people simultaneously. The Internet has also subsequently revolutionized shopping—for example; a person can order a CD online and receive it in the mail within a couple of days, or download it directly in some cases. The Internet has also greatly facilitated personalized marketing which allows a company to market a product to a specific person or a specific group of people more so than any other advertising medium. Examples of personalized marketing include online communities such as MySpace, Friendster, and others which thousands of Internet users join to advertise themselves and make friends online. Many of these users are young teens and adolescents ranging from 13 to 25 years old. In turn, when they advertise themselves they advertise interests and hobbies, which online marketing companies can use as information as to what those users will purchase online, and advertise their own companies' products to those users. A very ineffective way of advertising on the internet is through spamming an email with advertisements. This is ineffective because, now, most email providers offer protection against email spam. Most spam messages are sent automatically to everybody in the email database of the company/person that is spamming. This way of advertising is almost like using adware. Adware is another ineffective way of advertising because most people simply close a popup window when it shows up, not bothering to read it.

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Presented by: Tejas. B. Prajapati (MMS-II)-Systems FUTURE OF THE INTERNET THE MOBILE INTERNET

The Internet can now be accessed virtually anywhere by numerous means. Mobile phones, data-cards, and cellular routers allow users to connect to the Internet from anywhere there is a cellular network supporting that device's technology. BLOGS

One of the things that is so amazing amazing about blogs is their simplicity. simplicity. A blog blog is normally a single page of entries. A blog is organized in reverse-chronological order, from most recent entry to least recent. A blog is normally public -- the whole world can see it. The entries in a blog usually come from a single author. A blog is a lot like an online journal or diary. The author can talk about anything and everything. Many blogs are full of interesting links that the author has found. Blogs often contain stories or little snippets of information that are interesting to the author. Even though blogs can be completely free-form, many blogs have a focus. For example, if a blogger is interested in technology, the blogger might go to the Consumer Electronics Show and post entries of the things he/she sees there. th e author wants it to be. In other words, a blog can be anything the

Creating Your Own Blog Creating your own blog is now easy because there are Web-based toolsets that make the management of your blog incredibly simple -- Blogger Blogger,, Xanga Xanga,, TypePad TypePad,, and LiveJournal are just a few of the services available. You can create basic blogs for free. Creating a simple blog is free and only takes about five minutes. You enter your name, e-mail address and a few other pieces of information. You select "the look" (template) for your blog from a set of standard templates. Click a few buttons and you're done. Now you can add new entries to your blog. Basically, all you do is type in the entry and push the "post" button to post it. You can edit the entry as much as you like by clicking the "edit" button. When you are happy with the new entry, you push the "publish" button to make your new entry visible on your public blog. WEB 2.0 (refer video): Online collaboration with sharing data both by the user and by the website creator, Blogs, Vidoes, Photos, RSS Feeds and Online Applications today have created a place where everything is possible. This is Web 2.0

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Presented by: Tejas. B. Prajapati (MMS-II)-Systems CREATING A WEB-PAGE Web page - A Web page is a simple text file that contains not only text, but also a set of HTML tags that describe how the text should be formatted when a browser displays it on the screen.

An HTML tag is a code element that tells the Web browser what to do with your text. Each tag will appear as letters or words between a < (less than sign) and a > (greater than sign). HTML - HTML stands for Hyper Text Markup Language. A "markup language" is a computer language that describes how a page should be formatted. Viewing Page Source : With your mouse, right-click on any blank portion of this page and choose "View Source."

On your machine you have a program, or application, that can create simple text files. On Windows machines, this application is called Notepad. Once you have the proper program open on your screen, type (or cut-and-paste) the following HTML text into the window: My First Page Hello there. This is my first page!

Save it to the filename first.html. Next, open the page in your Web browser. When you open it in your browser, it will look  something like this:

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