Chapter 1: Internet

Learning Outcomes:Describe Internet works, Internet

providers, connections, and protocols.

Discuss e-mail, mailing lists, newsgroups, Internet relay chat, and instant messaging.

Describe Internet services: Telnet, FTP, and the Web.

What is Internet? A “network of networks” or “the

mother of all networks”.

What is Network? A system of interconnected

computers, telephones, or other communications devices that can communicate with one another and share applications and data.

History of InternetEarly 1960sEarly 1970s1980Late 1980sBy 1989By 19951999

Development of Internet in Malaysia

Year Event

1988 Establishment of RANGKOM network

1991 JARING network was introduced – 1st Internet Service Provider (ISP)

1997 Telekom Malaysia Berhad – 2nd ISP

How does the Internet work?Similar to the telephone system.

How to connect/access to the Internet?Through a provider or host

computer.Three widely used providers:-

Colleges and universitiesInternet service providersOnline service providers

Connecting to Internet

ConnectionsTo gain access to the InternetCan be made either directly to the

Internet or indirectly through a provider.

There are three types of connections:-Leased and dial-up line.SLIP and PPPTerminal connection

Leased and Dial-up lineLeased (Direct) line

Quite expensive Used by organization or corporationAdvantages:- complete access to Internet

functions, and fast response and retrieval of information.

Dial-up (Dedicated) lineA lower-speed connection using a modem and

the public phone system.Support only a single userAdvantages:- Inexpensive and available

everywhere.

Requirement to Access the Internet

ComputerModemAccountCommunication softwareInternet software

Internet AddressesTo send and receive e-mail on the

Internet.To interact with other networks.Every network and computer user must

have a unique address.Uses an addressing method known as

the domain name system (DNS).To assign names and numbers to people

and computers.DNS name – made of a domain and one or

more subdomains.Numerical – IP Addresses. E.g.:

128.16.4.23

Example of Internet address

lim.liyen@mmu.edu.my lim.liyen – user name @mmu.edu.my – domain name

@mmu – host computer edu – next-level domain / top-level domain my – highest-level domain

TCP/IP ProtocolBefore information/message is sent

over the Internet – it is broken down into small parts called packets.

Protocols control how messages are broken down, sent, and reassembled.They govern how and when computers talk

to one another.The standard protocols for the Internet

– transmission control protocol/Internet protocol.

World Wide Web (the Web)

Internet services that uses hypertext to link from document to document and from computer to computer.

Hypertext – a system in which documents scattered across many Internet sites are directly linked with hyperlinks.

Hypertext Transfer Protocol (HTTP) – the communication rules that allow browsers to connect with web servers.

Uniform Resource Locator (URL) – the web-site’s unique address.

Continue…Example of a URL

http://www.nps.gov/yose/camping.htmhttp:// - Protocolwww.nps.gov/ - Domain name (web server

name)yose/ - Directory name, or pathcamping.htm – File (document) name and

extensionBrowser – software that enables users to

view web pages and to link from one page to another.

HyperText Markup Language (HTML) – programming language for the documents files that are used to display Web pages.

Continue…Web page – a document on the WWW.

Web site – the location of a web domain name in a computer somewhere on the Internet.

Homepage – opening page of Web site.

Web server – a computer that delivers requested Web pages.

Webmaster – person who designs, creates, monitors, and evaluates corporate Web sites.

Continue…

How to find Information on the WWW?

Knowing the URL of the site.

Browsing

Search Engine

Browsing

E-mailA mode of communication via computer to send

and receive messages instantly from one network to another.

An E-mail system consists of two programs :-

User agents

Mail delivery system

E-mail address – used to send and receive messages.

A mail box – storage location residing in the computer that connects us to the Internet.

Mail server – the server that contains mailboxes.

Sending email

Continue…Simple Mail Transport Protocol (SMTP) –

controls the mail delivery within the Internet.

Post Office Protocol (POP) – communication protocol used to retrieve e-mail from a mail server.

Advantages:-

Very fast

Can be sent at the sender’s convenience

The recipient can read the message at his/her leisure

Easily be sent to one person, several, or to many.

Continue…E-mail Structure

Consist of two very important components:-

Header lines

To:

Cc:

BCc:

Subject:

Mail body

Continue…E-mail Software

Emotions

Address book

Mailing List

Signatures

Message Filters

Mail Folders

Attachment

Mailing ListsOne type of discussion group available on

the Internet.

Use e-mail subscription and list addresses.

Members of a mailing list communicate by sending messages to a list address.

List-serves (Listservs) – e-mail mailing lists of people who regularly participate in discussion topics.

TelnetA program or command that allows us to

connect to remote computers on the Internet using a user name and a password.

Useful for perusing large databases at universities, government agencies, or libraries.

Advantages:-We can be almost anywhere in the world

and telnet to your place of employment as if you were on site.

We can work on computer resources that may not be available locally.

FTP - File Transfer Protocol

A method whereby you can connect to a remote computer called an FTP site and transfer files to your own microcomputer’s hard disk.

FTP server – computer that allows user to upload and download files using FTP.

FTP site – a collection of files that reside on a FTP server.

Host computer – remote computer – accessible via Internet

Client computer – our own computerDownload – transfer of files from the host

computer – the client computer.Upload – vice versa

Continue… Basic steps in FTP:-

Make the FTP connection by logging in to the host computer.

Move to subdirectory where the desired file is stored.

Transfer the file from the host computer to client computer (or vice versa).

NewsgroupsGiant electronic bulletin boards on which

users conduct written discussions about a specific subject.

UseNet – special network of computers that support newsgroups.

News server – computer that stores and distributes newsgroup messages.

Newsreader – program included with most browsers that allows us to access a newsgroup and read or type messages.

Continue…Newsgroup classifications

alt. Alternative to the mainstream groups

comp. About computers

misc. Groups that don’t fit into any other categories

rec. About recreation

sci. About science issues

soc. About social science issues

talk. About debates on a variety of topics

news. About the newsgroup news

Chat GroupsAllow direct “live” communication.The most popular chat service – Internet

Relay Chat (IRC).IRC uses two of the basic components of a

TCP/IP based network:-IRC clientsIRC servers

Chat room – permits users to chat with each other.

Three type of chat rooms/channel:-PublicPrivateSecret

Instant MessagingAllows one or more people to communicate

via direct, “live” communication.

Provides greater control and flexibility than chat groups.

To get instant messaging – available free, download software and register with the service.

Netiquette“Network etiquette”

Guides to appropriate online behavior

Netiquette has two basic rules:

Don’t waste people’s time,

Don’t say anything to a person online that you wouldn’t say to his / her face.

SummaryThe Internet is a huge collection of computers

connected together by thousands of interconnected computer networks.

Through Internet Service Providers (ISP) - local or national companies that provide unlimited public access to the Internet and World Wide Web for a flat rate.

To send and receive e-mail on the Internet and interact with other networks, you need an Internet address.

WWW is a standardized set of requirements that allows users, from any point on the Internet, to access information at any other point.

SummaryEmail is a standardized set of requirements that

allows users, from any point on the Internet, to access information at any other point.

Mailing list provides a very easy method for sending messages to more than one Internet user.

Newsgroups is an online area in which users conduct written discussions about a particular subject.

IRC allows many people from around the world to communicate.

Instant Messaging (IM) is a real-time Internet Communications service that notifies you when one or more people are online

SummaryTelnet allows you turn your local computer

into a terminal of a remote host computer.FTP allows you to examine, send and receive

files from other computers over the Internet.