1 CSC317/318 INTERNET PROGRAMING / DYNAMIC WEB APPLICATION DEVELOPMENT CHAPTER: INTRODUCTION TO INTERNET II Siti Nurbaya Ismail Faculty of Computer & Mathematical.

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CSC317/318INTERNET PROGRAMING /

DYNAMIC WEB APPLICATION DEVELOPMENT

CHAPTER:INTRODUCTION TO INTERNET II

Siti Nurbaya Ismail

Faculty of Computer & Mathematical Sciences,

Universiti Teknologi MARA (UiTM), Kedah

| A2-3039 | [email protected] | 019-5710562 |

Introduction To Internet II

Internet Service Provider

Connecting to Internet

Protocols

How does data travel through the Internet?

Client/Server Communication

HTTP Communication for Web

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Introduction To Internet IIWhat is the Internet?

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Computer network the system in which a large

number of separate but interconnected computers serve all of the needs

a collection of interconnected networks

network of networks that consists of millions of private, public, academic, business, and government networks, of local to global scope, that are linked by a broad array of electronic and optical networking technologies

M’sia Net

S’pore Net

USA Net

India Net

Europe Net

Introduction To Internet IIIntranet? Extranet?

• Intranet– A PRIVATE computer network that belongs to an

organization that can be accessed ONLY by authorized persons

• Extranet– A part of an organization’s INTRANET that is

extended to user outside the company

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Introduction To Internet IIInternet Service Provider

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Internet Service Provider = ISP– Company that provide the Internet connection

M’sia Net/WAN(Local ISPs)

UiTM Net/LAN

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Desktop/Notebook

Dial-Up/xDSL Modem

Home

Firewall

Core Router

Firewall

Business/Organization

Introduction To Internet IIInternet Service Provider

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ISPs in Malaysia?– Answer: Quite a few

• Wired: * TMNET* Jaring* Maxis

• Wireless:* Jaring* Maxis * Celcom * Digi* iZZi

Introduction To Internet IIConnecting To Internet

Wired– Fixed line– Cable modem (dial-up | xDSL)– Network Interface Card (NIC)– LAN Cable– Fiber optic backbone from Server Exchange to CPE. Provided by ISP. In this

case provided by TM because TM own all underground cabling in Malaysia.

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Introduction To Internet IIConnecting To Internet

Wireless– IEEE 802.11

• Types: (A | B | G | N) or so called “Wi-Fi”• Access Point connected to wired LAN• Clients (notebook | desktop) connected

via wireless device– Embedded in the notebook or

external device such as USB wireless Adapter and PCI wireless card

• Coverage: (Small | Medium) because usually setup in an office, in a park or public spots

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Introduction To Internet IIConnecting To Internet

Wireless– IEEE 802.16

• Worldwide Interoperability for Microwave Access (WiMAX)

• Also known as Wireless MAN• Provides wireless internet

connection over long distances• Which companies won WiMAX

license in Malaysia last year?– Bizsurf, Packet One

Networks, Asiaspace Dotcom, Redtone-CNX Broadband, P1

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Introduction To Internet IIConnecting To Internet

Wireless– Satellite Internet Access

• Use mobile phone coverage: (GPRS | 3G | HSDPA)

• Modem (Supported mobile phone or USB Modem)

• Quite well-known these days• ISPs:

– Maxis Broadband– Celcom Broadband – Digi Broadband

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Introduction To Internet IIConnecting To Internet

Universal Resource Locator (URL)– An address to the current location of information

• protocol://host[:server port]/path/– Example:

• http://www.yahoo.com• http://www.uitm.edu.my/uitm

– Web browser uses the URL address to retrieve a document over the network

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Introduction To Internet IIConnecting To Internet

Domain Name– A name that uniquely identifies a website on the Internet– As a substitute for IP Address of the website– Example:

• URL : http://www.uitm.edu.my/uitm• Domain Name : uitm.edu.my• IP Address : 202.58.80.152

– Which one is easier to remember?• Domain name or IP Address?

– Top-level domain (TLD) names• Infrastructure (iTLD): .root, .arpa.• Generic TLD (gTLD): .com, .edu, .net, .gov, etc.• Country Code (ccTLD): .my, .uk, .id, .sg, etc.

Domain Name Server (DNS)– Translates domain name to IP Address

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Introduction To Internet IIConnecting To Internet

Host Name– A host is a (computer | device) that is connected to a network– Each host has a name, therefore, we call it host name– Host name uniquely identifies a host on a network without using its IP Address– Example:

• 1 computer named “uitmpc1” is connected to a UiTM’s network• “uitmpc1” has a unique IP Address which is “10.0.70.55”• You are able to access or find “uitmpc1” using its host name or IP Address

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Introduction To Internet IIProtocol

Protocol– A set of rules that enables computers to connect and transmit data to one another

over the network/Internet

– Examples:• Transmission Control Protocol (TCP)• Internet Protocol (IP)• Hypertext Transfer Protocol (HTTP)• File Transfer Protocol (FTP)• Simple Mail Transfer Protocol (SMTP)

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Introduction To Internet IIProtocol

Transmission Control Protocol (TCP)− TCP enables two hosts to establish a connection and exchange streams of data. − TCP guarantees delivery of data and also guarantees that packets will be

delivered in the same order in which they were sent.

Internet Protocol (IP)– IP specifies the format of packets, and the addressing scheme. – IP by itself is something like the postal system. It allows you to address a

package and drop it in the system, but there's no direct link between you and the recipient.

TCP/IP– defines the rule computers must follow to communicate with each other over the

Internet – defines how electronic devices (like computers) should be connected to the

Internet, and how data should be transmitted between them

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Introduction To Internet IIProtocol

Hypertext Transfer Protocol (HTTP)– underlying protocol used by the World Wide Web – defines how messages are formatted and transmitted, and what actions Web

servers and browsers should take in response to various commands. – Example, when you enter a URL in your browser, this actually sends an

HTTP command to the Web server directing it to fetch and transmit the requested Web page

File Transfer Protocol (FTP)– protocol for exchanging files over the Internet– most commonly used to download a file from a server using the Internet or to

upload a file to a server

Simple Mail Transfer Protocol (SMTP)– a protocol for sending e-mail messages between servers

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Introduction To Internet IIHow does data travel through the Internet?

At the most basic level possible, the diagram shows the step that brought the web page to your screen.

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Introduction To Internet IIHow does data travel through the Internet?

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Your computer ISPs

Routers

Web Servers

1. Your Computer sends page request and then translates the information sent

back into the words and images that make up the Web page

2. ISPs provide internet connection for home user and business or organization for a

fee

3. Routers are computers that receive information and forward it to the correct destination over the most efficient route

available at that moment

4. Web Servers are computers that answer your request for a particular Web

page with the information required to build that page on your computer

Introduction To Internet IIHow does data travel through the Internet?

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Web Servers

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Your Computer

01000011 01010011 01000011 00110011 00110001 00110111

Network/Internet

Bear in mind, data travel on the network/Internet in digital form (0|1)

Introduction To Internet IIClient/Server Communication

What is server?– A (software program | computer) that provides a specific kind of service to client

software running on the same computer or other (clients | computers) on a network

– Example:• Web server, file server, DHCP server

What is client?• A (computer | program | process) that makes requests for information from

another (computer | program | process) in a client-server relationship

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Introduction To Internet IIClient/Server Communication

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Client-side Server-side

Send request to the server

Return file to the client

Send another request to the server

Return required file to the client

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Introduction To Internet IIClient/Server Communication

Some of the protocols involved:– Hyper Text Transfer Protocol (HTTP)

• Port 80• Simple protocol for file transfer over the network/Internet

– File Transfer Protocol (FTP)• Port 21• Standard method for (sharing | downloading) files over the Internet for many

years• Commonly used to transfer Web page files from their creator to server.

* Note: Do you want to know the other port numbers? Visit http://www.iana.org/assignments/port-numbers

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Introduction To Internet IIClient/Server Communication

Common software requirement at the client side: Web browser– Internet Explorer– Firefox– Opera– Konqueror– Safari

Common software requirement at the server side: Web server– Microsoft Products: PWS or IIS– Open Source Products: Apache, Tomcat, etc.

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Introduction To Internet IIHTTP Communication for Web

Two types of Web:– Static Web

• The contents of the web are fixed• Hard coded in the HTML

– Dynamic Web• Dynamic content• The web is connected to the database• Required client and server side scripting

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Introduction To Internet IIHTTP Communication for Web

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Hello!

Hello

Can you give me index.php file?

Okay, here is the index.php fileClient Side Server Side

Introduction To Internet IIBibliography(website)

http://sitinur151.wordpress.com/ http://www.w3concepts.com/w3Main/GoverningTheNet.htm http://www.webopedia.com/ http://www.icann.org/tlds/ http://en.wikipedia.org/wiki/Top-level_domain http://en.wikipedia.org/wiki/Generic_top-level_domain http://en.wikipedia.org/wiki/Country_code_top-level_domain http://www.webdevelopersjournal.com/columns/ajs_who_controls_internet.html http://www.bellevuelinux.org/

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