INFORMATION AND COMMUNICATION TECHNOLOGIES IN EDUCATION

Internet and its application

Learning ObjectivesThe learner must be able to:

1. Define internet2. Identify other networks3. Explain the world wide web4. Explain how to web create the web

Internet, the definitions• The Internet is a global system of

interconnected computer networks that use the standard Internet protocol suite to serve billions of users worldwide.

• Internet, a system architecture that has revolutionized communications and methods of commerce by allowing various computer networks around the world to interconnect.

• However, a network is a cluster of computers, with one computer acting as a server to provide network services such as file transfer, e-mail, and document printing to the client computers or users of that network.

Internet, the definitions• The Internet is considered as network of

network• Using gateways and routers, a local area

network (LAN) can be connected to other LANs to form a wide area network (WAN).

• These LANs and WANs can also be connected to the Internet through a server that provides both the necessary software for the Internet and the physical data connection (usually a high-bandwidth telephone line, coaxial cable TV line, or wireless)

• The Internet carries an extensive range of information resources and services

• The Internet has no centralized governance in either technological implementation or policies for access and usage

Related Networking lexicons• Intranet• Extranet• Ethernet

Internet ServicesService

Purpose

ftp For transferring files between computers; can be anonymous or password protected (from File Transfer Protocol)

gopher

For menus of material available on the Internet (seldom used)

http For posting and reading documents (from the Hypertext Transfer Protocol used by the World Wide Web)

https For posting and reading encrypted (secure) documentsimap For receiving electronic mail (from Internet Message Access

Protocol)irc For real-time text messaging (from Internet Relay Chat)mud For real-time game playing (from MultiUser Dimension)pop For receiving electronic mail (from Post Office Protocol)rtsp For streaming media control (from Real Time Streaming Protocol)telnet For logging on and working from remote computerssmtp For sending mail (Simple Mail Transport Protocol)usenet For participating in discussion groups (from USERS NETwork)

Internet Services• Each Internet service is implemented on an

Internet server by dedicated software known as a daemon. (Actually, daemons only exist on Unix/Linux systems—on other systems, such as Windows, the services may run as regular applications or background processes.)

• Daemons are agent programs that run in the background, waiting to act on requests from the outside. In the case of the Internet, daemons support protocols.

History of the Internet• The Internet began as a research network

funded by the Advanced Research Projects Agency (ARPA) of the U.S. Defense Department, when the first node of the ARPANET was installed at the University of California at Los Angeles in September 1969.

• By the mid-1970s, the ARPANET “inter-network” embraced more than 30 universities, military sites, and government contractors, and its user base expanded to include the larger computer science research community.

History of the Internet• In 1989, responsibility and management for the

ARPANET was officially passed from military interests to the academically oriented NSF, and research organizations and universities (professors and students alike)

• Commercial and business use of the Internet was not permitted until 1992, but businesses have since become its driving force.

How the Internet Spread• Three inventions that spread the use of the Internet

were:• The personal computer (early 1980s)• The World Wide Web (1989)• The browser (1991)

The World Wide Web (www), definition• The World Wide Web (abbreviated as WWW or

W3, commonly known as the Web), is a system of interlinked hypertext documents (HTML doc) accessed via the Internet.

• Also seen as a wide-area hypermedia information initiative aiming at providing universal access to a large universe of information

Differences between the Internet and Web• The Internet and the WWW are not synonymous

How is information accessed on the Web• In its simplest expatiation

How is information accessed on the WebIn order to connect to the Internet you must have:• A modem: allows your computer to send

and receive signals through telephone lines• An Internet service provider (ISP):

required for all home connections• Browser software: might need plug-in

programs to retrieve some types of media applications

How is information accessed on the Web (Connecting to the Internet)

Modem (modulator-demodulator)• External Modem: This is a modem separated from

the system unit in the computer case. It is connected to the serial port of the computer by means of a cable. It is connected to the telephone wall jack by another cable.

• Internal Modem: An internal modem is a circuit board (a modem card) that can be added to the system unit of the computer. It takes one of the expansion slots.

How is information accessed on the Web (Connecting to the Internet)

An Internet service provider (ISP) or Internet access provider (IAP): ISPs employ a range of technologies to enable consumers to connect to their network through:• Dial-up• DSL (Digital Subscriber Line),• ADSL (typically Asymmetric Digital Subscriber Line)• Broadband wireless,• Cable modem,• Fiber to the premises (FTTH)

How is information accessed on the Web• What transpires on the Internet

How is information accessed on the Web (Connecting to the Internet)

Browser software (See below for further explanation):Is a software application for retrieving, and presentinginformation resources on the Wsorld Wide Web.Information the web is identified or located by Uniform Resources Identifier (URI) or Uniform Resource Locator (URL)Early browsers:• Mosaic = 1993 by• Nescape Navigator = 1994• Internet explorer = 1995

Web Browser, definition• Web browsers are information-rendering

software applications• software application for retrieving, presenting

and traversing information resources on the World Wide Web

• used to access information provided by web servers in private networks or files in file systems.

• Early browsers included WorldWideWeb (Nexus), Mosaic (Netscape) and Netscape Navigator

• Examples of popular web browsers include Google Chrome, Firefox, Internet Explorer (IE), Safari and Opera

Navigating the WebIn order to work with multimedia on the Internet, you must understand:• The browser screen and its standard

elements• URL addresses and the information they

contain

Features of Web Browsers

Dropdown Menu Tab Display

Address Bar

Search Bar with Search Engine

Refresh Button which doubles as Cancel button

Hit Display Area

Bookmarks Toolbar

Backward Button

Features of Web Browsers

Address Bar doubling as Search Bar ForwardButton

BackwardButton

Dropdown Menu

Features of URL / URI

https://www.schoology.com/assignments/index.html

Uniform Resource Locator / Uniform Resource Identifier

https://www.schoology.com/This address is an internet serve that uses hypertext transfer protocol

This represent the internet service know as World Wide Web

This belongs to a company calledSchoology. It is technically describedAs Domain Name

Surfing with Web Search Engine• Information resource gateway for surfing

information online• It is designed to search for information

on the World Wide Web.• Search results are referred to as Search

Engine Results Page (SERP) • SERP contain Hits populated on the

browser’s display pages• Hits = targets + source / Destination

Examples of Web Search EngineYahoo, Google, Bing, Yandex, AOL, Daemon, Baidu and Ask

Web Resource (Website)• Website is a set of related webpages

containing multimedia types and hosted on a server with a single domain name

• Webpage is an information resource, or specifically an HTML document suitable for the World Wide Web and can be accessed through a web browser

Form of Website• Static website (flat page): contains static

webpages and are delivered to the user exactly as stored (interaction takes place at client side)

• Dynamic website: contains active or dynamic pages, self automated and can customize it content based client interaction (dynamic code and dynamic content)

• Rich Internet Applications: desktop app with rich user experience. Web application that has many of the characteristics of desktop application software

Taxonomy of Website• Blog (weblog)• Electronic Commerce (e-commerce)• Gripe site• Gallery site• Dating Site• Phishing Site• Warez and Torrent Site• Question and Answer sites

Building a WebsiteTo build a website – dynamic or static- the developer must understand any of these fundamental scripting languages.HTML – Hypertext Markup Language: popular structural semantic language for structuring webpages. HTML 5 is the latestSGML – Standard General Markup Language DHTML – Dynamic Hypertext Markup LanguageXML – Extensible Markup Language XHTML – Extensible Hypertext Markup LanguageMXML – Macromedia Extensible Markup Language

Client/Server Architecture ( N-Tier)

Building a Website (client/server scripting language)

Client-side languages• HTML, CSS, JavaScript and AJAX Server-side language• PHP, Perl, ASP, Cold Fusion, Ruby on rail, JSP and

PythonDatabases (Relational Database Management System)• MySQL, NoSQL, Sybase, Oracle, MSSQL,Web Server Software• A web server (sometimes called an HTTP server or

application server) is a program that serves content using the HTTP protocol. E.g. Internet Information Service (IIS), Apache, Nginx, Lighttpd etc.

Building a Website (cont’d)

Tool for developing websites• Simple text editors• WYSIWYG offline editors• WYSIWYG online editors• Template-based editors

Deploying a Website (cont’d)• Websites are deployed on to a server for

world wide access

• Dedicated server, shared server or virtual server

• Buy domain name and server space ( monthly / yearly subscription) for a hosting service provider

• hosting service provider eg. GoDaddy, Hostgator, Google, Yahoo, aspspider etc.

Evolution of the WWW• Four altered evolutions emanating from

the web x.0 concept

Web 1.0• Publishing web or the info-centric web• Focused on primarily building the web,

making it accessible to the web client and commercializing the web for the first time

• Email communication was most effective

Web 2.0• Publishing web or people-centric web• Focused on participation, interaction and

collaboration• Application platform + personal computer

for communication• blogs, wikis, social networks, and RSS

feeds are web services that has brought about technical and social revolution

Web 3.0• Semantic web or Machine-centric web• Focused on connecting knowledge and

application• universal computing grid replacing

operating system and hard drive, resulting in large and dynamic groups of machines connected to each other.

• Web 3.0 is a convergence of several new technologies and service

Web 4.0• Intelligent web or Smart web or Agent-

centric web• Combines the power of human and

machine• enables the software agent(s) to reason

and communicate with other agents and systems and work collaboratively to accomplish things on user’s behalf (Agent-Centric)

Searching the Web

Use search engines to find the right Web page:• Create search queries that include

keywords.• Use Boolean search strategies to narrow

your search.• Use the right search engine to conduct

faster, more efficient searches.