1. Introduction to WWW and the Internet
Chapter 1
Introduction to WWW and the Internet
By : Madam Hazwani binti Rahmat

2. History of the Internet and WWW
COLD WAR ( )
History of the Internet and WWW ? 6
WWW 5
ARPA
net
NSF
net
DNS
TCP/IP 4 1 2 3
1969
1980
1983
1984
1990
201x

3. History of the Internet and WWW
In 1969, the Advanced Research Project Agency (ARPA) of the U.S Department of Defense (DoD) began connecting computers on different universities and defense contractors.
The resulting network was called ARPANET. The network included four primary host computers (Nodes at Uni. of California, Los Angeles (UCLA), Stanford Research Institute (SRI), Uni. of California, Santa Barbara (UCSB) and Uni. of Utah all with different operating system).

4. History of the Internet and WWW
Its goal:
to create a large computer network with multiple paths – in the form of telephone lines-that could survive a nuclear attack or a natural disaster such as an earthquake.
to allow people in remote locations to share scarce computing resources.
In the mid 1980s, another federal agency, the National Science Foundation (NSF), joined the project after the Defense Department stopped funding the network.

5. History of the Internet and WWW
NSF created a new, higher-capacity network, called NSFnet, to complement the older, and by then overloaded, ARPANET (The process of connecting separate networks is called internetworking).
The link between ARPANET, NSFnet, and other network (collection of networked networks ) was called the Internet.
NSFnet made Internet connections widely available for academic research, but the NSF did not permit users to conduct private business over the system. Therefore, several private telecommunications companies built their own network backbones that used the same set of networking protocols as NSFnet.

6. History of the Internet and WWW
The original ARPANET was shut down in 1990, and government funding for NSFnet was discontinued in 1995, but the commercial Internet backbone services replaced them.
By the early 1990s, interest in the Internet began to expand dramatically. The system that had been created as a tool for surviving a nuclear war found its way into businesses and homes.
Now, advertisements for movies are far more common online than collaborations on physics research. As a result, the Internet is open to anyone who can access it.

7. History of the Internet and WWW
In 1984, physicists from around the world needed to share data, with different hardware, software and individual requirement. Much work was done by   and file interchange. They needed to keep track of different things and different projects became involved with each other.
By Christmas 1990, Tim Berners-Lee had built all the tools necessary for a working Web: the HyperText Transfer Protocol (HTTP) 0.9, the HyperText Markup Language (HTML), the first Web browser (named WorldWideWeb, which was also a Web editor), the first HTTP server software (CERN httpd), the first web server , and the first Web pages that described the project itself.

8. The Internet Architecture
1)TCP/IP
2) IP Address
3) DNS
4) Internet Service
5) WWW
6) URL
7) HTTP
Figure: Protocols and Technologies which Composes the Internet

9. The Internet Architecture – IP Address
Internet Protocol (IP) Address
Unique identifier assigned to every computer, server and router that is connected to the Internet.
A number expressed in the format xxx.xxx.xxx.xxx
Each xxx is one byte long and can be any decimal value between 0 and 255.

10. The Internet Architecture – DNS
Domain Name System (DNS)
A hierarchical way of naming computer on the Internet.
Domain names always have two or more segments separated by dots. Each segment is a sub-domain, forming a hierarchical relationship.
Example : uthm.edu.my
Represents computers at UTHM
Represents country
Represents educational institution

11. The Internet Architecture – DNS
When a computer wish to communicate with another using domain name (request to load a web page), it will first check for the computer on local domain.
If it is found, it will establish the connection.
If it is not found, it searches for the computer through DNS servers.
Collection of these servers is known as Domain Name System.

12. The Internet Architecture – Internet Services
DESCRIPTION
Electronic Mail
( )
Main method of communication on the internet which allows messages or files to be sent to the accounts of other people on the same server as the sender or on server across the world.
Usenet
A collection of discussion groups called “newsgroups” specifically designed to create and facilitate ongoing discussions about specific subject areas. 
Telnet
A protocol where user command and program is used to log in from one computer to another remote computer via the Internet. Remote access is only granted if the user has permission and may require a login and a password to be entered.
File Transfer Protocol (FTP)
A method of connecting to another computer for the purpose of retrieving and / or sending files.

13. The Internet Architecture – WWW
The World Wide Web (WWW)
Is a portion of the Internet that uses a graphical interface known as web pages to represent it.
Web pages are written in a language called HTML (HyperText Markup Language) which dictates how a browser will load, format and align text and graphics on a web page.
Web pages are linked through hypertext links (link within text to other documents) embedded in the HTML code of a page.

14. The Internet Architecture – URL
Uniform Resource Locator (URL)
Is an address of web pages which identifies where the page is stored.
Consist of three parts (substrings): network protocol, host name, and file location.
The substrings are separated by special character, ‘/’
Example:
Protocol used to access resource
Location of resources in host folder
Host name

15. The Internet and WWW Protocols
Protocol is a standard way of communicating across a network. It is a method by which two dissimilar systems can communicate.
Example of protocols:
FTP – File Transfer Protocol
TCP/IP – Transmission Control Protocol / Internet Protocol
HTTP – Hypertext Transfer Protocol

16. The Internet and WWW Protocols
Transmission Control Protocol / Internet Protocol (TCP/IP)
Enable a network exchanges information with other network.
TCP: control the assembly of message into packets before it is transmitted over the Internet, and reassembly of the packets once they reach their destination.
IP: handle all the addressing details for each packet, ensuring that each is labeled with the correct destination address, which is the IP address.

17. The Internet and WWW Protocols
HyperText Transfer Protocol (HTTP)
Communication protocol for exchanging resources (HTML files, image files, query results) on the WWW between the web server and web browser.
HTTP defines what actions Web servers and browsers should take in response to various commands. 
For example, when URL is entered in the browser, this actually sends an HTTP command to the Web server directing it to fetch and transmit the requested Web page.

18. Static and Dynamic Programming Technique for Web Content Preparation
FEATURES
STATIC PROGRAMMING
DYNAMIC
PROGRAMMING
Technologies
HTML
JSP, ASP, PHP
Content
Rarely change
Dynamically change (database driven)
Functionalities
Basic information display
Browsing products / services.
Order tracking (received / shipped)
Inventory tracking (no. of available stocks)
Scheduling (availability)
Report generation
Advanced searching (by name, price range, etc.)

19. Static and Dynamic Programming Technique for Web Content Preparation (cont.)
Scenario 1
Online store info Web site contains only basic information about the store and offered products. Shoppers have to either visit the store in person or order a paper catalog.
Static Approach
Online catalog Clients can browse the catalog, see details of each catalog item, but they can't place online orders.
Both Approach
Online shopping Clients can browse and order products online.
Dynamic Approach

20. Static and Dynamic Programming Technique for Web Content Preparation (cont.)
Scenario 2
John owns a small bakery. One day he decides to advertise his business on the Internet. On his Web site, he wants to put information about breads, rolls, bagels, doughnuts, and cakes his bakery makes. Few times a year he comes with a new kind of bread or cake, so he would like his Web site to be updated when this happens. In addition, he wants to have a map with directions to help new customers with locating his bakery. He also decides that he is not going to sell his baking goods online.
Static Approach

21. Static and Dynamic Programming Technique for Web Content Preparation (cont.)
FEATURES
STATIC PROGRAMMING
DYNAMIC PROGRAMMING
Applicable Conditions
Products / Services offered don’t change much over time.
Web content (text, graphics) do not changed frequently.
The list of products and/or services is not very long and individual pages describing them can be easily constructed.
Database connection are not required.
No service / product offered.
Products / Services offered change frequently (adding / removing products/services)
Products / Services info change frequently (special promotions, new offer, inventory updates)
Large number of services / products
Web content relies on database records.

22. Static and Dynamic Programming Technique for Web Content Preparation (cont.)
FEATURES
STATIC PROGRAMMING
DYNAMIC PROGRAMMING
Advantages
Cheapest to develop
Cheap hosting cost
Offers various web functionalities
Easier to update content
Disadvantages
Lack of web functionalities
Requires development expertise to update web content.
Costly development
Cost more to be hosted

23. Web Server
Any computer that has a web server software installed and is connected to the Internet can act as a web server. [Ex: Apache, IIS]
A web server is a piece of software that enable a website to be viewed using HTTP.
Web server (host) stores and delivers(serves) requested web pages and other files.
Every computer on the Internet that contains a Web site must have a Web server program.

24. Example of Web Server – Internet Information Services (IIS)

25. Example of Web Server – Internet Information Services (IIS)1 2 3 4

26. Example of Web Server – Apache (XAMPP)

27. Example of Web Server – Apache (XAMPP)1 2 3 4

28. How Web Server Works?
Your web browser first needs to know which IP address the requested website resolves to. If it doesn't already have this information stored in it's cache, it requests the information from one or more DNS servers.
Then only it can request the full URL from the web server.
The web server responds by sending back the requested page. If the page doesn't exist (or another error occurs), it will send back the appropriate error message.
Finally, web browser receives the page and renders it as required.

29. Web Browser
Web browser (browser), is a program that interpret and displays web pages and enable user to view and interact with a web page.
Browser offers capabilities such as locating web pages, moving forward and backward between web pages, bookmark favorite web pages, and choosing security settings.

30. Functions of a Browser Display name of URLs
Translate name to Internet address
Request service of server holding document
Interpret and display document into readable format

31. Recap CHAPTER 1 HISTORY ARCH TECH. PROTOCOL TECHNIQUE STATIC DYNAMIC
WEB SERVER
WEB BROWSER