SAK3002 – IT and Its Applications Chapter 5SAK3002 – Information Technology and Its Application...

Chapter 5 SAK3002 – Information Technology and Its Application

SAK3002 – IT and Its Applications

INTERNETINTERNET55ChapterChapter



Objectives of this chapter:Objectives of this chapter:

Discuss the history of the Internet

Describe the types of Web sites

Explain how to access and

connect to the Internet

You can…

Imagine the future of the internet



OverviewOverview

This chapter covers Introduction History Internet Software Internet Services Future of the Internet



5.1 Introduction



What is the Internet? The largest network of networks in the world Uses TCP/IP protocols and packet switching Runs on any communications substrate

IntroductionIntroduction



Also called the Net One huge global interconnected networks that

comprised millions of computers A world-wide collection of networks that links

millions of businesses, government agencies, educational institutions, and individual

Internet services widely use – World Wide Web & e-mail

Introduction (cont’d)Introduction (cont’d)



A technology to link LAN network to a bigger network

Every computer in the network can directly share data and information with other computers

Internet Service Provider (ISP) are responsible to provide Internet services:

Examples: Jaring, MIMOS, TMNet, Telekom, Maxis.net , Time Telekom




“Galactic” Network A network that is connected globally where each

computers are able to retrieve data directly and share information

Every computer on the internet has an IP address (similar to a telephone number) and it is able to exchange data directly with other computers by “dialing” the computer’s address

The Internet uses packet switching concept where data sent are divided into smaller units known as packets

Each unit of packet has a number and destination address




Interoperability The Internet allows every computer in a network to

operate even tough each remote computers are of different brands and models or in a cross-platform network.

For example, a user can contact other computers like MAC, Windors PC, UNIX Machine and Mainframe using MAC.

Telnet is an example of an Internet service where a user can access a remote computer in a network after keying in login and password




High-speed connection

High-speed connection

Slow-speed technology

Slow-speed technology

How to connect to the Internet?

Dial-up accessmodem in your computer uses a

standard telephone line to connect to the Internet

Dial-up accessmodem in your computer uses a

standard telephone line to connect to the Internet

Digital subscriber line (DSL), cable telephone Internet

services (CATV), cable modem,fixed wireless, and satellite modems

Digital subscriber line (DSL), cable telephone Internet

services (CATV), cable modem,fixed wireless, and satellite modems

Connection is always on—whenever the computer

is running

Connection is always on—whenever the computer

is running

Connection must be established each time you log on. Slow but inexpensive

Connection must be established each time you log on. Slow but inexpensive




All computers have a unique Internet Protocol (IP) address.

All computers use TCP/IP protocol to communicate. Requires communication device like modem, ISDN

adapter, Ethernet card, telephone line

Download - to transmit data from a remote computer to a local computer

Upload - to transmit data from a local computer to a remote computer




TCP/IP Transmission Control Protocol/Internet Protocol (TCP/IP)

– a combined set of protocols that tells computers how to exchange information over the Internet.

TCP monitors and ensures correct transfer of data. IP receives the data from TCP, breaks it up into

packets, and ships it off to a network within the Internet.




Each Internet services require different protocols.

Examples like FTP and HTTP sit on top of TCP/IP.

FTP (File Transfer Protocol) – accessed using FTP browser or DOS prompt

HTTP (Hypertext Transfer Protocol) – accessed using Web Browser

POP3 and SMTP – accessed using Mail Browser




Role of ISP Access is provided by the Internet Service

Provider (ISP) i.e. Jaring, TMNet. ISP provides a back bone to the network – either:

PSTN (Public Switch Telephone Network) ISDN (Integrated Services Digital Network) or SONET (Synchronized Optical Network)

ISP also provide domain name registration for each organization.




What is a domain name?

Text version of Internet protocol (IP) address

Number that uniquely identifies each computer or device connected to Internet




Communication Link Shell Access

Usually by free shell account providers used for text-based email, IRC.

Modem and phone line temporary IP Computer providers that connect to the Internet (not

directly connect to Internet) Dial-up Point-to-Point (PPP)

Modem, phone line, ISDN adapter temporary IP Computer Internet




Cable/Satellites Dial-up with modem and phone line temporary IP. Faster transmission rate.

Leased Line Modem and dedicated line fixed IP. Usually to host Internet/Web Server. Support Extranet (external Internet) i.e. Sony Malaysia

and Sony Japan.




How the Internet WorksHow the Internet Works How might data travel the Internet using a cable modem connection?



5.2 History



1962 Started from Lickder’s “Galactic Network” idea that

introduced the concept of Packet Switching. RAND researchers concluded that Packet Switching was the best concept

1968 Lawrence G Roberts from DARPA formulated the

specifications for Advanced Research Agency Network (ARPANET)

1969 ARPANET connected 4 computers in California and

Utah, connecting university and research center with the Department of Defence (DoD) - USA

HistoryHistory



1973 ARPANET became an international network

1981 ARPANET connected 213 computers

1984 Total computers connected to ARPANET reached 1000

1987 Total computers connected to ARPANET reached 10,000

History (cont’d)History (cont’d)



Packet Switching In 1962, Galactic Network introduced the concept

of packet-switching, a new technology to transfer information between 2 distant computers

Packet-switching technology will break each message/data into smaller unit called packets for speedy and guaranteed delivery

Each packet carries a unique identification number and the destination address




ARPANET – (Advanced Research Projects Agency Network)

In 1968, L.G. Roberts from DARPA institute published a specification for Advanced Research Agency Network (ARPANET)

In 1969, ARPANET successfully connected 4 research computers in California & Utah

E-mail services was introduced in 1972 – people exchange text messages across a long distance

In 1973, ARPANET become international network




By 1981, ARPANET has 213 inter-connected computers called the Internet

In 1982, ARPANET was taken by DARPA and given to NSF (National Science Foundation)

In 1983, the Internet Protocol (TCP/IP) was introduced by Kahn & Cerf

By 1984 the network has grown to 1,000 computers and increased to 10,000 in the following 3 years




World Wide Web (WWW) In 1989, a researcher named Tim Berners-Lee

proposed the idea WWW while working at CERN (a physics laboratory in Europe)

In 1993, a group of professors and students at the University of Illinois National Center for Supercomputing Applications (NCSA) release mosaic – the first graphically based web browser




What is the World Wide Web (WWW)?

A worldwide collection of electronic documents

Each electronic document is called a Web page

Also called the Web

Can contain text, graphics, sound, video, and built-in connections

A Web site is a collection of related Web pages




5.3 Internet Software



Internet software allows user to use the services provided by the Internet

1. Web Browser Allows user to view web page and

browse Internet sites

Internet SoftwareInternet Software



Example of Web browser

MicrosoftInternetExplorer

Netscape

Firefox Opera

Mozilla

Safari

Internet Software - wwwInternet Software - www



How does a Web browser display a home page?

Step 1.Click the Web browser program name

Step 2.Web browser looks up the home page setting

Step 3.The Web browser communicates with the ISP’s server to retrieve the IP address. The IP address is sent to your computer.

Step 4.The home page displays in the Web browser

Internet Software - wwwInternet Software - www



2. Pager A software that allows a individual user to

communicate with other Internet users. Each user has to have the same software in their computer and register at a certain website for them to obtain an unique identity or ID

The user can then use this software by adding in other user’s ID in his/her pager software to be able to know whether the other user is online on the Internet

Internet Software (cont’d)Internet Software (cont’d)



It is usually used to communicate with other “known” individual; as the user needs to know the other user’s ID

Examples of pager softwares - Yahoo Messenger, ICQ and MSN Messenger etc

Some softwares such as Skype also allows user to communicate via telephone, using Internet as the intermediary medium




3. E-Mail A software that allows user to read, write and

store e-mails Examples of e-mail software – Microsoft

Outlook, Outlook Express, Netscape Messenger and Mozilla Thunderbird

4. Internet Relay Chat (IRC) A software that allows user to use Internet

Relay Chat services (Real-time Chat). An examples of IRC software – mIRC




5. Download Manager Allow users to download files to their computers It can continue to download the file if the user decide to continue

downloading at a later time, or if the user got disconnected and connected again from the network, without having to start the download again from the beginning of the file

However, to continue downloading from where you stop depends on the server that hosts the file(s). Note that not all server support this process

The software is also capable of searching other server that hosts the same file(s), which is faster and/or closer to the user’s location.

E.g. – FlashGet, Download Accelerator Plus, Godzilla and RealNetwork download manager




6. Internet Music Player Capable of playing music from the internet Some web pages like radio or tv station’s web sites,

provide a web based audio and/or video broadcasting/streaming through the internet. It can only be viewed using special software

Among the popular software are RealPlayer and Microsoft Media Player

This technology of listening/viewing audio/video through the internet is called “Streaming”




5.4 Internet Services



1. E-mail Used to send messages digitally through the

internet Every message delivery should have: address of

the recipient, address of the sender, subject of the message and body of the message

Email operations include - reply, forward, delete, save and print

Email will take a few seconds to be sent, it will be stored in the recipient’s email server until the recipient retrieves it. Then the recipient may reply, forward, delete, save or print the email

Internet ServicesInternet Services



[email protected]

User name/ID: azuramasura

Domain name: jpa

Top-level domain: .gov

Two-letter country extension: .my

Internet Services (cont’d)Internet Services (cont’d)



Other Internet ServicesOther Internet Services

How does an e-mail message travel?

Step 4.When recipient uses e-mail software to check for e-mail messages, the message transfers from incoming mail server to recipient’s computer

Step 2.Your software contacts software on your ISP’s outgoing mail server

Step 3.Software on outgoing mail server determines best route for data and sends message, which travels along Internet routers to recipient’s incoming mail server

Step 1.Using e-mail software, you create and send message



2. File Transfer Protocol (FTP) FTP is a protocol used to transfer (download or

upload) files between computers on the internet. FTP Client software can be used on PCs to

connect to FTP server. 2 types of modes to transfer files using FTP are:

ACII (text files) Binary (usually programs, graphics and

basically all other file types other than text)




Usually username and password is required to login to FTP service on a FTP server

Anonymous FTP is one way to connect to FTP server without having to identify yourself. Anonymous FTP example:

Type the following command on a DOS prompt

ftp ftp.jaring.myEnter the following username an password when askedLogin: anonymous or AnonymousPasswd: <enter your email address>




3. Newsgroup/Message boards


Newsgroup

Many Web sites use message boards because they are easier to use

Online area where users discuss a particular subject Message board

Type of discussion group



4. Chat Real-time typed conversation that takes place on a

computer Chat room is location on server that permits users

to discuss topics of interest Instant Messaging Example: mIRC, Yahoo Messanger, Skype, MSN

Messanger etc




5. Internet Telephony Real-time audio and video technology, such as Voice Over IP

(VoIP) and Video Conferencing is getting more popular VoIP techology uses three methods:

PC-to-PC – Using sound card, microphone and computer Phone-to-PC Phone-to-Phone – Using Telephones that support VoIP

The quality is not guaranteed (No QoS), There are noise and echo. All calls are charged as local calls.



6. Telnet Allows users to login to remote computers using valid

username and password. Users need to have an account on the remote computer. Issue the following command in DOS promt

telnet www.upm.edu.my A secured alternative to telnet is by connecting to remote

computer using SSH (Secure Shell)

ssh www.upm.edu.my The remote computer must have Telnet/SSH server

running for users to connect to it




7. Ping Allows users to check whether a remote computer is

up/operational. Type the following command in DOS prompt

ping www.upm.edu.my This command or service might not work properly if:

The server or user is behind a firewall and it blocks ICMP request. Your ISP does not allow this type of request. The server has an embedded firewall on it and it blocks ICMP

request.




8. Web Sites A framework architecture used to share and access

documents that is connected to the internet Information displayed are intuitive, easy to use and using

interesting graphical interface Information are exchanged using client server concept. A web document that interconnects pages is called

hypertext A text string that links a page to other pages is called a

hyperlink Hypertext that contains other media (graphics, audio,

video, etc.) is called hypermedia WWW is a world wide hypermedia and hypertext system




Every address is unique and is called Universal Resource Locator (URL)

http://www.jaring.my/intro/index.html

URLs consists of 4 parts: Protocol: HyperText Transfer Protocol

(HTTP) Server: Internet domain name Path: The location of the document

in the server- folder/directory name Resources name: The filename, usually in one of

these formats html/cgi/sound/movie/graphic

protocol

serverpath File name

Internet Services (cont’d)-websiteInternet Services (cont’d)-website



What is Search engine

Program used to find Web sites and Web pages by entering words or phrases called search text

Also called a keyword




What is a hit? Any Web site name that is listed as the result of a search

Step 4. Click link to view Web site

Step 1. Go to search engine

Step 2.Select type of search you wantto run

Step 3. View hits




Advocacy Blog WikiSocial

NetworkContent

AggregatorPersonal

Portal


News InformationalBusiness/Marketing

Educational Entertainment

12 basic types of Web sites




A Web site that offers a variety of services from one, convenient location, usually for free

Searching, news, sports and weather, Web publishing, reference tools, stock quotes, maps, shopping, e-mail, and online communities (Web sites that join people with similar interests)

Portal Web site



News Web site

Contains newsworthy material Stories and articles relating to current events, life,

money, sports, and the weather




Informational Web site Contains factual information Created by organizations and government agencies




Business/marketing Web site Contains content that promotes products or services Allows you to purchase products or services online




Educational Web site

Some companies offer online training for employees

Some colleges offer online classes and degrees

Offers avenues for formal and informal teachingand learning




Entertainment Web site Offers an interactive and engaging environment

featuring music, video, sports, games, and more




Advocacy Web site Contains content that describes a cause, opinion,

or idea





Short for Weblog Uses a regularly updated

journal format to reflect the interests, opinions, and personalities of the author and sometimes site visitors

Video blog (vlog), blogosphere, and vlogosphere

Blog web site



Wiki web site Collaborative Web site that allows users to add to,

modify, or delete the Web site content via their Web browser





Encourages members to share their interests, ideas, stories, photos, music, and videos

Media sharing Web site Other example?

Friendster Facebook Hi5 Geni (family tree)

Online social network



Content aggregator web site Business that gathers and organizes Web content and

then distributes, or feeds, the content to subscribers for free or a fee




Personal Web site Web page maintained by private individual Reasons: sharing life experience with the world

or job hunting




Graphics formats are used on the Web

BMPBMP

GIF(pronounced JIFF)

GIF(pronounced JIFF)

JPEG(pronounced JAY-peg)

JPEG(pronounced JAY-peg)

TIFFTIFF

PNG(pronounced ping)

PNG(pronounced ping)




What is streaming audio/video?

The process oftransferring audio/video

in a continuousand even flow

Enables you tolisten to music/ watch video

as it downloadsto your computer

Example of a web site offers video streaming: www.youtube.com

Example of a web site offers audio streaming: www.i-bands.net/bandlist.php




NetiquetteNetiquette What is netiquette?

Golden Rule: Treat others as you would like them to treat you.

Code of acceptable behaviors users should follow while on the Internet



5.5 Future Of The Internet



Very High-speed network 1 Gigabyte per-second speed

Interoperability A Network that links with almost

everything Example: TV, House, Car etc.

imagine something? Please share to the class

Future Of The InternetFuture Of The Internet



End of Chapter 5

SAK3002 – IT and Its Applications Chapter 5SAK3002 – Information Technology and Its Application...

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