What is the Internet

1
"What is the Internet?"

• a cooperatively-run collection of computer
  networks that span the globe

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Introduction

• Definition
• History
• How the Web was created
• Typical Web Site
• Constituents
• How is it paid for ?
• How does it work
• Web Servers
• Commercialisation

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Definition

• The Internet, in simplest terms, is the large
  group of millions of computers around the world
  that are all connected to one another. These
  computers are connected by phone lines, fibre
  optic lines, coaxial cable, satellites, and
  wireless connections.
• When you log on to the Internet you are given
  access to many of the other computers that are
  connected around the world.
• Some common ways of connecting to the Internet
  include
• Internet service provider (ISP) by modem
• Internet ready cable
• digital subscriber line (DSL)
• simply turning on your computer which is on a
  network at work or school connected to the
  Internet
• Today you can even get a wireless connection to
  the Internet with a handheld PC or notebook
  computer.
• Once you are connected to the Internet you are
  able to do many things. You can send and receive
  e-mail. You can chat with text or voice. You can
  browse the World Wide Web. And you can perform
  countless other tasks with the appropriate
  software.
• If the satellite or undersea cable appeared to be
  busy with other Internet data, your mail server
  may try sending west through Australia or Japan.
  In theory, the e-mail, although probably just a
  few paragraphs may possibly be broken into two or
  more parts and half of it would be sent east and
  half west. All the pieces would be reconstructed
  in London in one piece for your friend to read
  next time they log on.
• The Internet is very dynamic. Routers and other
  computer server hardware try to find the best
  lines between servers so you get the best
  possible service. All of these connections are
  transparent to you, the Internet User. All of
  these connections look just like a direct
  connection to you. It makes using the Internet a
  lot easier.

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History

• Many people think that the Internet is a recent
  innovation, when in fact the essence of it has
  been around for over a quarter century. The
  Internet began as Arpanet, a U.S. Department of
  Defence project to create a nationwide computer
  network that would continue to function even if a
  large portion of it were destroyed in a nuclear
  war or natural disaster.
• During the next two decades, the network that
  evolved was used primarily by academic
  institutions, scientists and the government for
  research and communications. The appeal of the
  Internet to these bodies was obvious, as it
  allowed disparate institutions to connect to each
  others' computing systems and databases, as well
  as share data via E-mail.
• The nature of the Internet changed abruptly in
  1992, when the U.S. government began pulling out
  of network management, and commercial entities
  offered Internet access to the general public for
  the first time. This change in focus marked the
  beginning of the Internet's astonishing
  expansion.
• The Internet explosion coincides with the advent
  of increasingly powerful yet reasonably priced
  personal computers with easy-to-use graphical
  operating systems. The result has been an
  attraction of recent computer "converts" to the
  network, and new possibilities for exploiting a
  wealth of multimedia capabilities.
• For further details on the Internet's history, go
  to http//www.internetvalley.com/intval.html

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How was the Web created ?

• The World-Wide Web began in March 1989, when Tim
  Berners-Lee of the European Particle Physics
  Laboratory (known as CERN, a collective of
  European high-energy physics researchers)
  proposed the project to be used as a means of
  transporting research and ideas effectively
  throughout the organization. Effective
  communications was a goal of CERN's for many
  years, as its members were located in a number of
  countries.
• The initial project proposal outlined a simple
  system of using networked hypertext to transmit
  documents and communicate among members in the
  high-energy physics community. There was no
  intention of adding sound or video, and the
  capability to transmit images was not considered.
  
• By the end of 1990, the first piece of Web
  software was introduced on a NeXT machine. It had
  the capability to view and transmit hypertext
  documents to other people on the Internet, and
  came with the capability to edit hypertext
  documents on the screen.
• Throughout 1992 small handfuls of developers
  began to volunteer their time into working on
  small pieces of the World-Wide Web puzzle.
• Since then hundreds of people throughout the
  world have contributed their time writing Web
  software and documents or telling others about
  the Web. In a way never envisioned by the
  original project group, the project has reached
  global proportions.

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What does the Web look like ?

• The World-Wide Web exists virtually - there is no
  standard way of viewing it or navigating around
  it.
• The browser has
• A menu bar
• A scroll bar
• Although there are many different ways to
  represent a document on the screen, it is often
  called a page.
• This type of document is called a home page and
  is generally associated with a particular site,
  person, or named collection. The example shows
  the Flower Shop's home page.
• hyperlink (or link) - typically, clicking on it
  with a mouse will cause another document to
  appear on the screen, which may hold more images
  and hyperlinks to other places.
• Images such as the flower picture which are part
  of the document and are displayed within the page
  are called inline images.
• At the bottom of the screen is a set of
  navigation buttons
• The back button shows the previously viewed
  document.
• The forward button would show the pages in the
  order the user previously viewed them.
• An open button allows the user to connect to
  other documents and networked resources by
  specifying the address of the document or
  resource to connect to.
• The print button allows the user to print out the
  document seen on the screen. The user may be
  given the choice of printing the document with
  images and formatting as seen on the screen or as
  a text-only document.
• The page lists an email address
• A convention on the Web is to name the person in
  charge of administrating a World-Wide Web site a
  "webmaster" - any problems with the hyperlinks,
  images, documents, or questions about the site
  should be mailed to a webmaster address.

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What Makes Up the Internet?

• Unlike many computer networks, the Internet
  consists of not one but multiple data systems
  that were developed independently. The most
  popular and important systems are
• E-mail, for exchange of electronic mail messages.
  
• USENET newsgroups, for posting and responding to
  public "bulletin board" messages.
• File Transfer Protocol (FTP), a system for
  storing and retrieving data files on large
  computer systems.
• Gopher, a method of searching for various
  text-based Internet resources (largely obsolete).
  
• TELNET, a way of connecting directly to computer
  systems on the Internet.
• Internet Relay Chat (IRC), a system for sending
  public and private messages to other users in
  "real time"that is, your message appears on the
  recipient's screen as soon as you type it.
• CU-SeeMe, a videoconferencing system that allows
  users to send and receive sound and pictures
  simultaneously over the Internet.
• The World Wide Web.

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Who Governs the Internet?

• The Internet has no president or chief operating
  officer. There's no single authority figure for
  the Internet as a whole. The ultimate authority
  for where the Internet is going rests with the
  Internet Society, or ISOC. ISOC is a voluntary
  membership organization whose purpose is to
  promote global information exchange through
  Internet technology.
• The council of elders is a group of invited
  volunteers called the Internet Architecture
  Board, or the IAB. The IAB meets regularly to
  approve standards and allocate resources, like
  addresses. The Internet works because there are
  standard ways for computers and software
  applications to talk to each other. This allows
  computers from different vendors to communicate
  without problems. It's not an IBM-only or
  Sun-only or Macintosh-only network. The IAB is
  responsible for these standards it decides when
  a standard is necessary, and what the standard
  should be.
• Internet users express their opinions through
  meetings of the Internet Engineering Task Force
  (IETF). The IETF is another volunteer
  organization it meets regularly to discuss
  operational and near-term technical problems of
  the Internet. When it considers a problem
  important enough to merit concern, the IETF sets
  up a "working group" for further investigation.
  (In practice, "important enough" usually means
  that there are enough people to volunteer for the
  working group.)
• The World Wide Web Consortium was created in
  October 1994 to lead the World Wide Web to its
  full potential by developing common protocols
  that promote its evolution and ensure its
  interoperability. W3C has around 400 Member
  organizations from all over the world and has
  earned international recognition for its
  contributions to the growth of the Web.

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Who Pays for It?

• The old rule for when things are confusing is
  "follow the money." Well, this won't help you to
  understand the Internet. No one pays for "it"
  there is no Internet, Inc. that collects fees
  from all Internet networks or users.
• Instead, everyone pays for their part. The NSF
  pays for NSFNET. NASA pays for the NASA Science
  Internet.
• Networks get together and decide how to connect
  themselves together and fund these
  interconnections.
• A University pays for their connection to some
  regional network (MidMAN), which in turn pays a
  national provider for its access (JANET).

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How does the Internet work ?

• The Internet is a worldwide collection of
  computer networks, cooperating with each other to
  exchange data using a common software standard.
  Through telephone wires and satellite links,
  Internet users can share information in a variety
  of forms. The size, scope and design of the
  Internet allows users to
• connect easily through ordinary personal
  computers and local phone numbers
• exchange electronic mail (E-mail) with friends
  and colleagues with accounts on the Internet
• post information for others to access, and update
  it frequently
• access multimedia information that includes
  sound, photographic images and even video and
• access diverse perspectives from around the
  world.
• An additional attribute of the Internet is that
  it lacks a central authorityin other words,
  there is no "Internet, Inc." that controls the
  Internet. Beyond the various governing boards
  that work to establish policies and standards,
  the Internet is bound by few rules and answers to
  no single organization.

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Web Servers

• The Internet may be considered as a large network
  of computers
• A Web Server is a network server that manages
  access to files, folders and other resources over
  the Internet, or a local Intranet via the
  platform-neutral HTTP (Hypertext Transfer
  protocol)
• A Web Server is a machine which may run one of
• Microsofts Personal Web Server
• Microsofts Internet Information Server
• Apache
• Netscape Enterprise Server
• Web Servers handle browser requests
• When a browser requests a page or file from a web
  server, the server processes the request and
  returns an answer to the browser

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Web Servers (2)
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Web Servers (3)

• Use such protocols as HTTP (HyperText Transfer
  Protocol), FTP (File Transfer Protocol) and SMTP
  (Simple Mail Transfer Protocol)
• The Web Sever, using HTTP, accepts HTTP requests
  from Web Browsers (Internet Explorer, Netscape,
  Opera etc) and returns the requested HTML pages,
  images, embedded Java applets etc
• This can be enhanced by a number of server-side
  (running on the Web Server) technologies.
• These include CGI scripts, server-side includes,
  SSL security, Java servlets, ASP etc

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Web Servers (4)

• Although a Web Server may be considered a network
  server, it has unique web networking features
• Handles permissions
• Executes programs
• Keeps track of directories and files
• Communicates with client computers
• A server may be a powerful PC, a minicomputer or
  even a mainframe.
• Many Web Servers run on the UNIX operating system
  (60), although an increasing number use
  Microsofts NT OS (40) ZD Net Tech InfoBase

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Browsers

• Browser War is now over with Internet Explorer
  having emerged the winner
• IE did not always have the lion share of the
  market
• The first browsers, Viola and Midas, were
  released in January 1993 for the X - Window
  system (Unix). At the same time, a Macintosh
  browser was released as an ALPHA - version.
• www, a line mode browser, was available for the
  public on 15th January 1992 via telnet.
• Mosaic one of the earliest of browsers (1992),
  became a Killer App in 1993
• Developer went on to found Netscape, still no
  entry by MS

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Browsers (2)

• Microsoft wakes up to potential of Internet
  (1995)!
• IE given away free (IE3 1996), Browser War
  begins
• MS Antitrust Case
• Market Share Feb 2001 IE 6 (88), Netscape
  (12) www.statmarket.com
• Netscape launches Gecko small and fast, open
  source users help in development (as in Linux)
• Dont forget Opera ! (www.operasoft.com)

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Browsers (3)

• Browsers rely on plug-ins, such as Java, Flash
  etc
• Web Pages relying increasingly on multimedia
  content
• Streaming Video/Audio, Web Casts, Web TV
• Access to Web from a variety of devices,
  especially on the move
• Devices accessing Web will outnumber PCs in 2004
  (source BT)

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Web Server Usage
Source Netcraft Survey December 2003
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Web Browser Statistics
Source QinetiQ ltd (UK Government) July2003
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What Does This Mean for Me?

• Obviously, the Internet can bring you a whole
  host of capabilities. But how can they be put to
  practical use?
• Among the ways that users like yourself are
  taking advantage of the Internet are
• Sharing research and business data among
  colleagues and like-minded individuals.
• Communicating with others and transmitting files
  via E-mail.
• Requesting and providing assistance with problems
  and questions.
• Marketing and publicizing products and services.
• Gathering valuable feedback and suggestions from
  customers and business partners.
• The Internet's potential is limited only by
  users' vision and creativity. And as the Internet
  grows, new and innovative uses will surely follow.

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What Does the Future Hold?

• Wireless
• Streaming media
• Convergence
• Charging
• All Pervasive
• Virtual reality
• Commercialisation
• Primary form of communication
• Paying for access to sites
• Paying for services (Hotmail)
• Paying for quality information
• Intranets

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Questions ?