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The Internet and the Web

Irfan A. Ilyas

Lecture 23

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Points to coverPoints to cover Introducing Introducing InternetInternet

What is availableWhat is available on the Internet? on the Internet? How to get connectedHow to get connected with Internet? with Internet?

Main Internet FacilitiesMain Internet Facilities World Wide WebWorld Wide Web Electronic MailingElectronic Mailing TelnetTelnet FTPFTP GopherGopher

Basic Working Model of Internet ServicesBasic Working Model of Internet Services

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Introducing InternetIntroducing Internet

Internet is Internet is a a connectionconnection of billions of computers (similar/ of billions of computers (similar/

dissimilar)dissimilar)ANDAND

the technologiesthe technologies (hardware/ software) which (hardware/ software) which makes the whole setup makes the whole setup interoperableinteroperable..

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What is available on the Internet?What is available on the Internet?

Internet Internet offers its users many servicesoffers its users many services including including CommunicationCommunication with others with others

Using emails, chatting (online messaging)Using emails, chatting (online messaging)

ShoppingShopping Buy goods (and sell also)Buy goods (and sell also)

SearchingSearching Reading materials from real as well as virtual librariesReading materials from real as well as virtual libraries

EntertainmentEntertainment Games, Magazines, Interactive games etc.Games, Magazines, Interactive games etc.

EducationEducation (e-learnings) (e-learnings) Take online classes, get academic degrees.Take online classes, get academic degrees.

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How to get connected with Internet?How to get connected with Internet?

Internet Service ProviderInternet Service Provider (ISP) (ISP) An ISP is a commercial based organizationAn ISP is a commercial based organization ISP charge their customers on hourly or fixed basis ISP charge their customers on hourly or fixed basis

(unlimited access)(unlimited access)

How it works?How it works? An ISP An ISP already had its computer connectedalready had its computer connected with the with the

Internet (backbone)Internet (backbone)

ISP ISP allows their users to get connectedallows their users to get connected with their local with their local computer through a modem (telephone line)computer through a modem (telephone line)

After the user is connected, After the user is connected, he becomes a part of the he becomes a part of the InternetInternet (using different services) (using different services)

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……How to get connected with Internet?How to get connected with Internet?

Internet Service Providers( ISP )Internet Service Providers( ISP ) Commercial OrganizationsCommercial Organizations

Available for all public Available for all public Centers are locally available to different areas [saves Centers are locally available to different areas [saves

telephone charges].telephone charges]. ExamplesExamples::

Saudi Online, Nasjeet etc.Saudi Online, Nasjeet etc. Provide their customers with different numbers in Riyadh, Provide their customers with different numbers in Riyadh,

Dammam, Jeddah etc. Dammam, Jeddah etc.

University & CollegesUniversity & Colleges Only available for University attached people (students, Only available for University attached people (students,

faculty, staff)faculty, staff) Cannot be used from other localitiesCannot be used from other localities ExampleExample: KFUPM Connection: KFUPM Connection

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……How to get connected with Internet?How to get connected with Internet?

Procedure for an ISP connectionsProcedure for an ISP connections Step#1: Getting Tel# & User AccountStep#1: Getting Tel# & User Account

Subscribers are provided with Subscribers are provided with A telephone number to the ISP computer (local A telephone number to the ISP computer (local

to the subscriber’s locality)to the subscriber’s locality) A username & passwordA username & password

Saudi Online Prepaid Card with necessary information printed over itSaudi Online Prepaid Card with necessary information printed over it

Note: pre-paid card from commercial ISPs normally have this information printed over it.

Saudi OnlineUser Name: 99847756Password: fdjfdkfkdjfddfd

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……Procedure for an ISP connectionsProcedure for an ISP connections

Step#2: System Setup for a dialup Step#2: System Setup for a dialup ConnectionConnectionTo To prepare the subscriber’s (user) prepare the subscriber’s (user)

systemsystem for the connection, one of the for the connection, one of the following will also be provided:following will also be provided: A A step-by-step manual setupstep-by-step manual setup procedure procedureOROR A A small program which will automatically small program which will automatically

do the required setupdo the required setup using a dialogue using a dialogue from the user.from the user.

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……Procedure for an ISP connectionsProcedure for an ISP connections

Step#3: Connecting the ISPStep#3: Connecting the ISP Using the dialup connection created in Using the dialup connection created in

the last step, the last step, Users dial the ISP numberUsers dial the ISP number System tries to connect (strange noise)System tries to connect (strange noise) A successful connection message appearsA successful connection message appears

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……Procedure for an ISP connectionsProcedure for an ISP connections

Step#4: Using Internet Step#4: Using Internet FacilitiesFacilities Users can now start browsing Users can now start browsing

etc. etc.

For more info: http://www.saudionline.com

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Access ProvidersAccess Providers

Common way to attach to the InternetCommon way to attach to the Internet

Internet service providers (Internet service providers (ISPISP))

NationalNational

RegionalRegional

WirelessWireless

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Main Facilities on InternetMain Facilities on Internet

World Wide WebWorld Wide Web WWW allows Internet computers to WWW allows Internet computers to exchange information exchange information

objects (text/ pictures/ sound etc.)objects (text/ pictures/ sound etc.) among each other through among each other through easy to use web pages.easy to use web pages.

WWW is an interface of Internet contentsWWW is an interface of Internet contents

Electronic MailingElectronic Mailing Sending and receiving messages using InternetSending and receiving messages using Internet

TelnetTelnet Running programsRunning programs on a remote computer (with its screen and on a remote computer (with its screen and

keyboard control available locally)keyboard control available locally)

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…….Main Facilities on Internet.Main Facilities on Internet

FTPFTP Transferring file from/ to a remote computer on the InternetTransferring file from/ to a remote computer on the Internet

GopherGopher It allows a client computer It allows a client computer to access different resources on a to access different resources on a

server computer using a menu based interfaceserver computer using a menu based interface (text based (text based menus)menus)

Not very popular after WebNot very popular after Web Interface became available. Interface became available. Complex and painful. Complex and painful.

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The Basic Working Model of Different The Basic Working Model of Different Internet ServicesInternet Services

Client RequestsA Server Computer running the server program A Web Client Computer

[running the client program]

Server Responses

All Internet facilities work on the same principle All Internet facilities work on the same principle as does the Web Service.as does the Web Service. A A client program client program is provided to Internet usersis provided to Internet users

WWW: WWW: Internet Explorer, Netscape NavigatorInternet Explorer, Netscape Navigator EmailEmail: Outlook Express, Netscape Mailer, Eudora Mail: Outlook Express, Netscape Mailer, Eudora Mail FTPFTP: Cute FTP for windows, : Cute FTP for windows, TelnetTelnet: Microsoft Windows Telnet client: Microsoft Windows Telnet client

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Example: Client ProgramsExample: Client Programs

Cute FTP for Cute FTP for WindowsWindows

Microsoft Window Microsoft Window Telnet ClientTelnet Client

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… … Working Principle of Different Internet Working Principle of Different Internet ServicesServices

A A server programserver program must be running on the computers must be running on the computers providing any related service.providing any related service. Normally available as “Normally available as “Operating System ServicesOperating System Services”” Services start automatically when windows startsServices start automatically when windows starts

Service handling a Telnet Server Facility

Service handling a WWW Server Facility

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… … Working Principle of Different Internet Working Principle of Different Internet ServicesServices

The The transaction mechanismstransaction mechanisms needed in each needed in each service will be different but already service will be different but already standardizedstandardized EmailEmail: Simple Mail Transfer Protocol (SMTP): Simple Mail Transfer Protocol (SMTP) FTPFTP: File Transfer Protocol (FTP): File Transfer Protocol (FTP) GopherGopher: Gopher Protocol: Gopher Protocol WebWeb: Hyper Text Transfer Protocol (http): Hyper Text Transfer Protocol (http)

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