MR AZIZUL ZAMRI BIN MUHAMED AMIN WEB : Your Logo

Transcription

1 MR AZIZUL ZAMRI BIN MUHAMED AMIN WEB : Your Logo

2 Chapter 1 Introduction to WWW and the Internet By : Azizulzamri bin Muhamed Amin

3 History of the Internet and WWW COLD WAR ( ) 6 WWW ARPA net NSF net 1 2 TCP/IP 3 DNS x

4 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.

5 In the mid 1980s, another federal agency, the National Science Foundation (NSF), joined the project after the Defense Department stopped funding the network. History of the Internet and WWW Its goal: 1)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. 2)to allow people in remote locations to share scarce computing resources.

6 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

7 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

8 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

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

10 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

11 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. Represents computers at UTHM Example : uthm.edu.my Represents educational institution Represents country

12 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

13 The Internet Architecture Internet Services SERVICES Electronic Mail ( ) Usenet Telnet DESCRIPTION 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. A collection of discussion groups called newsgroups specifically designed to create and facilitate ongoing discussions about specific subject areas. 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.

14 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

15 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, / Protocol used to access resource Location of Example: Host name resources in host folder

16 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: 1)FTP File Transfer Protocol 2)TCP/IP Transmission Control Protocol / Internet Protocol 3)HTTP Hypertext Transfer Protocol

17 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

18 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,

19 Static and Dynamic Programming Technique for Web Content Preparation FEATURES Technologi es Content Functionali ties STATIC PROGRAMM ING HTML Rarely change 1) Basic informatio n display 2) Browsing JSP, ASP, PHP DYNAMIC PROGRAMMING Dynamically change (database driven) 1) Order tracking (received / shipped) 2) Inventory tracking (no. of available stocks)

20 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 Both can't place online orders. Approach Online shopping Dynamic Clients can browse and order products online. Approach

21 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 Static locating his bakery. He also decides that he is not Approach going to sell his baking goods online.

22 Static and Dynamic Programming Technique for Web Content Preparation (cont.) FEATUR ES Applica ble Conditi ons STATIC PROGRAMMING 1) Products / Services offered don t change much over time. 2) Web content (text, graphics) do not changed frequently. 3) The list of products and/or services is not very long and individual pages describing them can be DYNAMIC PROGRAMMING 1) Products / Services offered change frequently (adding / removing products/services) 2) Products / Services info change frequently (special promotions, new offer, inventory updates)

23 Static and Dynamic Programming Technique for Web Content Preparation (cont.) FEATURES Advantag es Disadvant ages STATIC PROGRAMMING 1) Cheapest to develop 2) Cheap hosting cost 1) Lack of web functionalities 2) Requires development DYNAMIC PROGRAMMING 1) Offers various web functionalities 2) Easier to update content 1) Costly development 2) Cost more to be hosted

24 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.

25 Example of Web Server Internet Information Services (IIS)

26 Example of Web Server Internet Information Services (IIS)

27 Example of Web Server Apache (XAMPP)

28 Example of Web Server Apache (XAMPP)

29 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

30 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.

31 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

32 Recap CHAP TER 1 HISTORY WEB SERVER WEB BROWSER ARCH TECHNIQUE TECH. PROTOCOL STATIC DYNAMIC

33 THANK YOU Slide 33 of 8