Memoire Online - Design and implementation of a web portal on sustainable development in Cameroon

I, SONAGOU TAKAM Yvon Berthet hereby declare that I am the sole author of this dissertation. I authorize the Higher Technical Teacher Training College (H.T.T.T.C), Bambili to lend this thesis to other institutions or individuals for the purpose of scholarly research.

I understand the notion of plagiarism, and I am aware of university policy on this.

I certified that this dissertation reports original work by me during my university project, except for the paragraphs, sentences, titles and subtitles already referenced (see References, webography or bibliography) on this work.

CERTIFICATION

I hereby certify that this dissertation entitled Design and implementation of sustainable development web portal in Cameroon has been carried out by M. SONAGOU TAKAM Yvon Berthet, with registration number 13T0788 in the Department of Computer Sciences, and of the option Information and Communication Technology (ICT) of the Higher Technical Teacher Training College (H.T.T.T.C) Bambili, University of Bamenda.

The work is therefore approved for a contribution to scientific knowledge and literacy presentation for the award for the «Higher Technical School Teacher Post Graduate Diploma (DIPET II) option Information and Communication Technology».

DEDICATION

ACKNOWLEDGEMENTS

At the end of my dissertation, I would like to thank all those people who madethis possible and an unforgettable experience for me:

· I wish to express my sincere thanks to Dr. DADA Jean-Pierre, my supervisor, for his patience, motivation, enthusiasm, and immense knowledge, for providing me with all the necessary facilities for the research.

· I place on record, my sincere thank you to M. ATANGANA Romain,Head of Department, for the continuous encouragement.

· I am also grateful to the Teachers of the Department for sharing their expertise, for their guidance and encouragement extended to me.

· I take this opportunity to express my gratitude to Pr. AKUME Daniel AKUME, Director of the H.T.T.T.Cfor the availability of all the resources of his institution to our formation.

· I also thank my parents for the unceasing encouragement, financial support and attention.

· I would like to thankmy classmates and friends who have supported and encourage me through the duration of the dissertation project.

· I also place on record, my sense of gratitude to one and all, who directly or indirectly, have lent their hand in this venture.

ABSTRACT

This dissertation, entitled «Design and implementation of sustainable development web portal in Cameroon " is intended as a solution to problems of communication between the actors of sustainable development in our country since the establishment of such a development model requires communication and information tools powerful and reliable. Thus this work was completed at the H.T.T.T.C ofBambili during the academic year 2014-2015.

Accordingly, the construction of such an application required a design phase which is made using the MERISE method leading to the selection of tools to help us achieve our web application. The web portal for sustainable development thus constructed provides to Cameroonians anews service, a library, a system of external hyperlinks, a forum service, a members area with internal mail, an internal search engine, a Google custom search just like a content proposal system..

RÉSUMÉ

Ce mémoire, intitulé « Conception et réalisation d'un portail web de développement durable au Cameroun » se veut une solution aux problèmes de communication entre les acteurs du développement durable dans notre pays vu que la mise en place d'un tel modèle de développement exige des outils de communication et d'information puissants. C'est ainsi que ce travail fut mené à l'E.N.S.E.T de Bambili durant l'année académique 2014-2015.

Partant, la construction d'une telle application a nécessité une phase de conception qui s'est fait à l'aide de la méthode MERISE débouchant sur le choix des outils devant nous permettre de réaliser notre application web. Le portail web de développement durable ainsi construit met à la disposition des camerounais un service d'actualité, une librairie, un système de liens externes, un service forum, un espace membres avec messagerie interne, un moteur de recherche interne, une recherche personnalisée Google, tout comme un système de proposition de contenu.

TABLE OF CONTENT

LIST OF FIGURES

LIST OF TABLES

LIST OF ABBREVIATIONS

CHAPTER ONE: GENERAL INTRODUCTION

1. BACKGROUND AND CONTEXT OF THE STUDY

The various economic, social and environmental crises that the majority of countries of planet are experimenting today, seems to be the result of the capitalist model of development disseminated in the world by the Occident. Capitalism is this model of development which gives the priority to the economic growth. Consequently the level of development at the beginning of the 20^th century is being measured with the capacity of the states to accumulate richness. Later the social factor makes its appearance and one then will measure the development from an economic and social point of view.

However, with the apparition of the oil crisis in 1973 and 1978, the Occident was become aware of a possible shortage of the natural resources. Also, a significant parameter of the development had been put on side: the environment. The model of industrial development seems non-viable. Therefore, related to the problem of viability which is equity clings, the more poor undergo more on the ecological crisis which prevails.

The model of development of the moment seems to be highly consuming non-renewable resources. At the same time, with the multiplication of ecological crises, it appeared urgent to redefine a new way of development taking into account all the parameters of a healthy development. This idea comes out as a result in 1980, from the concept of "sustainable development" that appears in a report of the International Union for Conservation of the Nature (IUCN).

In 1992, the United Nations Conference on Environment and Development (UNCED) published the «Earth Charter», which outlines the building of a just, sustainable, and peaceful global society in the 21^st century. The action plan Agenda 21 adopted by 173 countries amongst which the Cameroon for sustainable development identified information, integration, and participation as key building blocks to help countries achieve development that recognizes these interdependent pillars. It emphasizes that in sustainable development everyone is a user and provider of information. It stresses the need to change from old sector-centered ways of doing business to new approaches that involve cross-sectorial coordination and the integration of environmental and social concerns into all development processes.

Cameroun for its part inherited after the independence the capitalist system characterized by the drainage of the natural resources towards outside to the detriment of the local population and especially of the environment. It is in this logic that the multiplication of social crisis as well as environmental crisis such as: desertification, pollution, climatic disturbances have occur. Thus, the Cameroonian leaders choose a model of sustainable development through the adhesion of Cameroon to Agenda 21observable in many fields particularly those of energy and agriculture. However a rapid seen of the political flow chart of our country reveals insufficiencies. Because the sustainable development is based on three principal pillars the social one, the economy, and the environmental pillar which is disseminated within many ministries. These ministries overlap remains weak while the sustainable development requires actions coordinated on all the levels whatever they are.

At the same time, the Internet Word Stats reproduced a report of the International Telecommunication Union (ITU). This report, taking into account the proliferation of computer science and Internet, observed that there are 1,006,000 Cameroonians which uses Internet in June 2012. This number represents at this time nearly 5? of the population. Today this percentage is re-examined, so, according to the World Bank more than 6.4? Cameroonians go on Internet in 2013 what testifies a constant penetration of Internet within Cameroonian society. Also one of greatest attractions of Internet is web portal, shown by their proliferation in Cameroon treating in general of subjects like employment, news, economy and even of Internet. Another important thing to note is that amongst the 10 favorite websites of Cameroonians 6 are web portals according to Internet Word Stats.

2. STATEMENT OF THEPROBLEM

The sustainable development from its scale (the fact that it puts forward all the actors of the life of a nation) requires the existence for this model of development of tools of communication and information reliable and powerful. Therefore, the popularization of the computer science and especially of Internet makes us foresee a web portal as solution to this problem. Hence the web portals from the diversity of the services which can be associated to him come out like one of the serious alternatives for the diffusion of the sustainable development in our country. The construction of a Web portal having to be used as platform of information, communication and exchanges, training for the public services, the private academics, NGOs, companies and individuals look necessary.

3. RESEARCH QUESTIONS

· Is it possible to ameliorate the interchange of information among all the actors of sustainable development in Cameroon through a web application?

4. RESEARCH HYPOTHESES

· The actual economic and social growth, change of environmental conditions in Cameroon ask to improve the level of web services specially in the domain of sustainable development ;

· Sustainable development improving knowledge and communication should have an impact on the way people perceive their society and their environment.

5. OBJECTIVES OF THE STUDY

5.1. GENERAL OBJECTIVE

The general objective of this work is to build a user-friendly web application, actually a web portal, in order to improve communication and information amongst the different actors of sustainable development in Cameroon.

5.2. SPECIFIC OBJECTIVES:

By the end of this dissertation, with the appropriate use of database software and software, we should be able to:

· Put in place a news page on sustainable development which can be update online;

· Build a sharing space forum on varies theme concern by sustainable development;

· Put in place a library in relation to our topic from which users must be able to download document.

6. SIGNIFICANCE OF THE STUDY OR ACHIEVEMENTS

Although there already exists in Cameroon many web portals, and that many researches have already been carried on the construction of web application, this research project aims the construction of a web application in the field of sustainable development which remains inexistent in our country. This project goes beyond initiation to scientific research and of the mastering of web programming tools to contribute to future work which will be carrying on the building of applications web and also those concern by sustainable development of which it could be used as platform of collection of information.

7. SCOPE OF THE STUDY

This study is based on analysing the general way web developer used to design and implement web application, taking into consideration the particularities of web portals.

The research also takes as important parameter the main aspects of sustainable development, his main component or pillars (economic, social, environment).

8. DELIMITATION OF THE STUDY

This work is for all people, Cameroonian or not interested by sustainable development.

- An administration space for the webmaster to update the website, and to manage the forum.

9. IMPORTANCE OF THE DISSERTATION FOR EDUCATION COMMUNITY

By putting in place a web portal of sustainable development we may improve communication and information amongst all the actors and person interested by sustainable development in our country. This subject is also an opportunity to master the tools and languages related to web programming.

For educational community it can be a tool for improving knowledge and exchanging of point view.

10. DEFINITION OF TERMS

The United Nations World Commission on Environment and Development in its 1987 report Our Common Future defines sustainable development as the : "Development that meets the needs of the present without compromising the ability of future generations to meet their own needs." Under the principles of the United Nations Charter the Millennium Declaration identified principles or pillars and treaties on sustainable development, including economic development, social development and environmental protection. Broadly defined, sustainable development is a systems approach to growth and development and to manage natural, produced, and social capital for the welfare of their own and future generations. The concepts of sustainable development and sustainability derive from the older forestry term "sustained yield", which, in turn, is a translation of the German term "nachhaltigerErtrag" dating from 1713. Sustainability science is the study of the concepts of sustainable development and environmental science. There is an additional focus on the present generations' responsibility to regenerate, maintain and improve planetary resources for use by future generations.

Sustainable development is defined as development process that balances ecological, economic and social and establishes a virtuous circle between these three poles: it is a development, economically efficient, socially equitable and ecologically sustainable. It is respectful of natural resources and ecosystems, life support on Earth, ensuring economic efficiency, without losing sight of the social purposes of development such as the fight against poverty, against inequality, against exclusion and search for equity. A strategy for sustainable development must be winner of this triple point of view, economic, social and ecological.

Sustainable development requires that human decisions and behavior in reconciling what appears to many irreconcilable, manage to expand their vision: it requires to open our time horizon over the long term, that of future generations and our spatial horizon in taking into account the well-being of everyone, whether a resident of the South or the North, a nearby region of the city or neighbouring district.

Different domains have been identified for research and analysis of sustainable development. Broadly defined, these include ecology, economics, politics and culture as used by the United Nations and a number of other international organizations. As a working definition, sustainability can be defined as the practice of maintaining processes of productivity indefinitely (natural or human made) by replacing resources used with resources of equal or greater value without degrading or endangering natural biotic systems.

Sustainable development is based on research integration and alignment of sectorial policies set imposes joint processing of economic, social and environmental effects of any policy or human action. Such an approach requires integration of multi-partnership approaches and interdisciplinary. Its success is based on partnership and cooperation between actors from different disciplines (economics, sociology, ecology) from different sectors (transport, water, waste, natural environment, social development) and different environments (entrepreneurial, associative, institutional, administrative, commercial, trade union), acting at different territorial levels, from international to local level.

Sustainable development is in fact based on a new form of governance, where the mobilization and participation of all actors of civil society in decision-making should take precedence over the mere exchange of information. Sustainable development aims to promote participatory democracy and restore civic approach. Access to information and transparency are prerequisites.

Internet is a world system of interconnection of network, using a standardized whole of protocol of transfer of data. It is therefore a network of network, composed of million networks as well public, private, university, commercial and governmental. Internet transports a broad spectrum of information and allows the development of applications and services varied like the electronic mail, the instantaneous messenger and the World Wide Web.

Internet having been popularized by the appearance of the World Wide Web, both is sometimes confused by the public. The World Wide Web is however only one of the applications of Internet.

The access to Internet can be obtained through an Internet service provider via various means of communication: either telegraphic (ADSL, optical fiber to the residence), or without wire (WIMAX, by satellite).

The World Wide Web, commonly known as the Web, sometimes the Web, literally the "web (spider) World" is a public hypertext system operating on the Internet that provides access with a browser, uploaded pages in sites. The image of the web has hyperlinks that link web pages together.

The Web is only one of the Internet applications, with email, instant messaging, Usenet. The Web was invented several years after the Internet, but the Web has made the mainstream media attention to the Internet. Since the Web is often confused with the Internet; in particular, the word is often used Canvas very ambiguously.

The World Wide Web is and has been designated by many synonymous names and acronyms: WorldWideWeb, World Wide Web, World-wide Web, Web, WWW, W3, Web of Spider World, World Wide Web, Web.

The name of the original project was WorldWideWeb. The words were quickly separated into World Wide Web to improve readability. The name World-Wide Web was also used by the Web inventors, but now recommended by the World Wide Web Consortium name separates the three words without a hyphen. Spelling World Wide Web and the Web abbreviation are now well established.

Surfing the web is like walking into an endless jungle. We never see the end so there websites, and found it absolutely everything.

According to Wikipedia a website is a set of related web pages typically served from a single web domain. A website is hosted on at least one web server, accessible via a network such as the Internet or a private local area network through an Internet address known as a Uniform resource locator. All publicly accessible websites collectively constitute the World Wide Web.

A website can be defined as a set of linked websites together by hyperlinks, accessible through the Internet using a web address (URL) from the same domain name. Sometimes the term is used website, which is equivalent (Internet is the network which supports the web, but the shade is not of fundamental importance in this case).

A website consists of web pages as' they are in a computing resource available on the Internet and read by a web browser (Firefox, Chrome, Internet Explorer). In general, when talking about web page, we think of a html document containing text, images, videos or any other type of resources. However, a simple image with a URL (therefore accessible through the Internet) may be considered by extension as a web page. The web is primarily based on the connection between multiple pages that make references to each other. This is called hypertext links (or hyperlinks). We find these links in the navigation menus or in the body of web pages.

It is possible to make connections between the pages of a website in the same way we can to point these links to web from other websites pages. We talk in a case of internal links in the other external links.

The web portal term draws its origin from Latin Medieval "portale", meaning the main entrance of the city.

Portal sites are websites whose primary purpose is to provide users with resources and services related to a theme, a profession, a geographic area or community.

Resources may be links to other sites reference discussion forums or blogs, but can also consist of editorial content specific to the gate. These services can be of different types: Engine Specialized searches; email.

The term portal is a good metaphor to describe these web portals to a "dedicated universe."

We still define a web portal as a web site trying to offer the broadest pallet of information and possible services in only one site. It is a web site which offers a single door of entry on a broad range of resources and services (electronic mail, forum of discussion, spaces of publication, search engine) centered on a field or a particular community. The users have most of the time the possibility of being register and to connect later on and use the whole of services suggested to them. A web portal provides also services such as the capacity for the user to personalize his workspace. The user thus has access to the activity of current purse, the weather report, the profiles of other users who use the gate, and several types of information according to the individual interest of the user.

We can distinguish 02 main classes of web portals: vertical web portals constitute an entrance point specialized in a specific place of the market or a domain of industry, it is the case of forbes.com. Horizontal web portal is used like a platform for several organizations and covers a variety of information in various sectors (yahoo.com for example).

So, according to Wikipedia we have many types of web portal: personal portals, government web portals, cultural portals, corporate web portals, stock portals, search portals, tender portals, hosted web portals, domain-specific portals.

- It does not offer only links to third party websites from one category but offers related services and editorial content it owns.

- Allows usually (but not always) the user to register in order to be able to customize its interface and use the associated services.

- 11. OVERVIEW OF DISSERTATION

To achieve our general objective, the present study is organized around five chapters.

The first chapter, entitled «General introduction» was already been done. It contained the context and background of the study, the problem statement, the objectives, the questions of research, the hypothesis, the objectives of research as well as the delimitation of the subject.

«Literature review and materials used» is the title of chapter two. Here will be devoted to the preceding studies undertaken by other researchers. We will be focused on documents relating to the construction of a Web application or better on the construction of a web portal.

The chapter three, Methodology of research and materials used, in this part, the procedures that were applied to collect data. Data processing techniques and the research design are also presented. This chapter ends with materials (software and hardware) we will use to implement our web portal.

Chapter four is concern by «Results and Findings and discussion». Then the chapter five shall carry on the summary, conclusion, recommendations and suggestions for further studies.

The last chapter entitled «General conclusion» will help us to summarize all our findings, a small conclusion is done. We will list some recommendations ad suggestions for further studies in relation with this topic.

CHAPTER TWO: LITERATURE REVIEW

INTRODUCTION

It is nowadays quite undeniable that the internet has revolutionized the world since its effects will soon spread into the lives of everyone at all levels. The explosive growth of the Internet has given place to the creation of new businesses that have relied on a plethora of services on the powerful programming languages as well as web application development quality steadily to accustom user needs to.

Web applications are about to revolutionize the way we communicate throughout the world. The communication rules are thus upset because the distance is no longer one of the key factors. And besides, internet through web applications is one of the major communication tools to promote a considerable time, a variety of services, and easier access to information. Thus, the construction of a reliable web application involves the fairly clear understanding of what a web application on the one hand; and secondly a look will be devolved to the principal that has been identified for the construction of web portal. This chapter begins with an overview of web applications, and finishes with some ideas coming from dissertations.

1. OVERVIEW OF WEB APPLICATIONS

A web application also called a dynamic website (since a static website is more like a tool of communication which do not allow interaction with users) is a software application manipulated through a web browser. In the same way that web sites, web application is usually placed on a server and handles by activating widgets using a web browser via a computer network (Internet, intranet, LAN).

The Webmail, content management systems (CMS), blogs are web applications. Search engines, e-commerce software, online games, forum software may be another form of web application. Network devices including routers, for example are sometimes equipped with a web application in their firmware. Thus a web application aims to accomplish specific task like when we make a research on Google. The impact of web applications on how to operate a business, to transmit and receive information, and even on people's lives, is considerable and in more than four decades programmers have tried to jump the barriers between traditional applications and web applications.

It is important to note that the success of web applications is due to many advantages that can be summarized through several points:

· In terms of time, the implementation and deployment of a web application is faster, the flow and sharing of data between users as optimized as much as we enjoy the most intuitive applications and easier to handle (to through the web browser).

· In terms of accessibility, access can be done through many types of devices (PC, phone), operating systems constraints do not exist here; work or access can be done from anywhere in the world and as a bonus the data is accessible 24hour / 24 and 7days on7.

· In terms of costs, access to web applications at a cost entirely predictable based on the subscription chosen by the customer and many features are free of charge.

· In terms of security, user data is stored in large processing centers (Data Center) very reliable.

· As bonus, web applications are steadily increasing and dynamism they have shown is unparalleled.

1.1. History of web applications

The interactive web applications slowly revolutionized the way we use the Internet. The concept of web application is not recent. Indeed, one of the first programming languages for web application development was the "Perl". It was invented by Larry Wall in 1987 before the internet became accessible to the general public. But it was in 1995, when the programmer RasmusLerdorf made the PHP language available to all that the Web application development really took off. Today, even most of the famous of these web applications are developed in PHP including Google, Facebook and Wikipedia.

A few months later, Netscape, ancient and popular web browser, announced a new technology, JavaScript, allowing programmers to dynamically change the content of a Web page that was, until now, static text. This technology allowed a new approach in the development of Web applications, which were now, and still today, much more interactive for users. For example, the Google Instant feature for displaying search results even as the letters of the word is typed, makes heavy use of JavaScript.

The following year, in 1996, two developers, Sabeer BHATIA and Jack Smith, launched Hotmail an online messaging service. This allowed (for the first time) to the general public to access and check e-mail anywhere users could be on the planet and thus away from their workstation (computer).

Then came the famous Flash platform for adding interactive content to websites. Flash came on in 1997 under the name of Shockwave Flash. Later, after being acquired by Macromedia and now by Adobe, Flash became a development platform for interactive Web applications.

Subsequently the use of web applications will know many bouncing including online journalism beginning that will place internet as an entire media. So, things were greatly facilitated by Google in 1998, when the company launched its first online search engine which by its new way to index Web pages, greatly facilitated the search for information on the internet. Google continued to innovate and became one of the most prolific companies in terms of Web applications, listing the popular Google Maps, Google Docs, Gmail and others.

However, it is until 2004, at a conference on "Web 2.0" that appears for the first time the concept of "Web as a platform." This innovation paved the way for future web applications, that is to say, the software that takes advantage of the internet and moving away from the traditional use of the desktop.

1.2. The Internet and the Web

Internet is a worldwide system of interconnected computer network, using a standardized set of data transfer protocol. This is a network of network without nervous center, composed of millions of networks public, private, academic, commercial and governmental. Internet carries a wide band of information and allows the development of applications and various services such as email, instant messaging, and the World Wide Web.

Internet access can be obtained through an Internet Service Provider through various means of electronic communication, either wired (telephone network, ADSL, fiber) or wireless (WIMAX, satellite). An Internet user at that time is designated by the term "surfer".

Internet is constituted of the plurality of networks spread worldwide and interconnected. Each network is attached to a separate entity (ISP Internet) and is associated with a unique identifier called Autonomous System (AS) used by the routing protocol BGP (Border Gateway Protocol). In order to communicate, network exchange data, either by establishing a direct link, or by attaching to an exchange node (peering point). These exchanges may be limited to traffic between their respective users (called peering) or include third traffic (it is then transit agreement). An operator that provides Internet transit service to other service providers is called carrier. These peering are free; they are not subject to regulation by a central authority.

Each network is connected to one or more other networks. When data is to be transmitted from one computer to another belonging to a different AS, it is then necessary to determine the way to perform among the networks. Routers, charge of traffic between the AS usually have a complete routing table (Full routing table) of more than 330,000 routes in 2010, and send traffic to a neighbour router closer to the destination after consulting their routing table.

To access the internet you must have an IP device and a connection to an ISP. For this, the user uses the following hardware and software:

· E-mail software: SMTP and POP client or IMAP offered by Mozilla thunderbird, Microsoft outlook.

· File Transfers software: a client or FTP (File Transfer Protocol). They may include Filezilla

· Peer to peer: one of many P2P software based on use (sharing peer-to-peer files, Distributed Computing).

Internet operates on a layered model similar to the OSI model. The elements belonging to the same layers use a communication protocol to exchange information. A protocol is a set of rules that define a language for communicating multiple computers. They are defined by open standards.

Each protocol has its own functions and together they provide a range of ways to respond to the multiplicity and diversity of needs on the Internet.

1.3. Types of websites

Basing the classification on the technologies used while building the websites and the interaction with the user, we can have the following types of websites:

A static website is made up exclusively of website files stored on a server and sent directly to the client browser to enable the display of pages. Updating a static site is performed by the addition of HTML files in the storage site. There is no back office. The daily management of such a site can quickly become laborious: To add a link to a new page, add this link to all existing pages and therefore modify each file one by one. This is made easier by specialized software, but it is tedious.

Primarily a static site is coded in Hypertext Mark-up Language (HTML). Cascading Style Sheets (CSS) are used to control appearance beyond basic HTML. Images are commonly used to affect the desired appearance and as share of the main content.

This kind of website usually displays the same information to all visitors. Similar to handing out a printed brochure to customers or clients, a static website generally will provide consistent, standard information for an extended period of time. Although the website owner may make updates periodically, it is a manual process to edit the text, photos and other happy and May require basic website design skills and software. Simple forms or marketing examples of websites, Such As classic website, a five-page website or a brochure website are often static websites, because they present pre-defined, static information to the user. This may include information about a company and its products and services through text, photos, animations, audio / video, and navigation menus.

Static websites can be created of edited using the following categories of software:

Static websites may still use Server Side Includes (SSI) as an editing convenience, such as sharing a common bar across many pages menu. As the website's behaviour to the reader is still static, this is not considered a dynamic site.

A dynamic website is one that changes or customizes itself frequently and automatically, here, clients can interact with each other and with the application, the information is automatically updates and sometime those website offer an administration space.

Server-side dynamic pages are generated "on the fly" by computer code that produces the HTML and CSS. There are a wide range of software systems, such as CGI, Java Servlets and Java Server Pages (JSP), Active Server Pages and ColdFusion that are available to generate dynamic web systems and dynamic sites. Various web application frameworks and web template systems are available for general-use programming languages like PHP, Java-EE, Perl, Python, and Ruby, to make it faster and easier to create complex dynamic web sites. But amongst all those languages PHP is the most used and belong to the ten most used programming languages in the world with Java.

When interviewing a website, a server sends an HTML/CSS code for your browser displays the web page you request. To build the HTML/CSS code, the server can use two methods:

- It builds the code from a model (static part) and data stored on a database (the dynamic part)

- Ease of Use: Dynamic websites are more frequently used. Indeed, they allow users, for example through the use of CMS, to easily add to and edit a website without having to intervene directly in the source code for it.

- Construction of elaborate web sites: Thanks to the use of a database, it is possible to produce pages that can adapt to the user request, which may otherwise also contribute content. One can for example propose research with custom criteria, or the opportunity to comment on a page.

The main disadvantage of a dynamic site is that it is slower than a static site. Indeed, it must go through an intermediate step of querying the database, wait for data and send them to the user after compilation.

For the same reasons, dynamic websites require more resources to operate machine. This is what drives some organizations to turn to static sites like Jekyll systems.

Dynamic web sites might be more convenient to use for users, they are nevertheless much more complex computer systems perspective. A static site requires zero maintenance and is easy to install, but a dynamic website should be regularly updated to work and requires more complex starting configurations (eg for the connection with the database). A dynamic site also requires additional resources to operate (PHP).

Of course, from the moment it is possible to connect to a site management system (back office) and where there is connection to a database, the security holes are more than a static site. We must therefore ensure the integration of security aspects in the design of a dynamic website, including and especially when using a CMS like WordPress or Joomla market.

Flash is a vector animation system developed by Adobe editor. To play a flash animation, a plug-in (Flash Player for example) must be installed on your browser. The full flash websites have only one web page index.html. Calling this page from the server causes the page to load a flash file like "animation.swf". Thus the index.html page contains a link to the animation file that contains all the animations of the site. So the full flash websites may have the following characteristics:

- They offer the ability to create interactive applications by using action script

- There are no compatibility issues when that flash technology is installed on the browser

- By creating a flash animation, it is ensured that the design will remain the same from one computer to another or from one browser to another.

Note that flash animations are already used on many website but partially like on YouTube where it is used to display video content.

This category of web site is based on the AJAX architecture (Asynchronous JavaScript and XML).

In a web application, the conventional method of dialogue between a browser and a server is as follows: at each manipulation made by the user, the browser sends a request containing a reference to a web page and the web server performs calculations and sends the result as a web page to the browser. This will display the page he has just received. Each manipulation results in the transmission and display a new page. The user must wait for the answer to perform other manipulations.

Using Ajax, the dialogue between the browser and the server takes place mostly in the following way: a program written in JavaScript programming language, embedded in a web page, is executed by the browser. It sends in the background requests to the Web server, and then changes the content of the page currently displayed by the web browser based on the result received from the server, thus avoiding the transmission and display of a complete new page.

Instead, the operation of Ajax programming requires JavaScript exchanges between the browser and the Web server. It also requires you to program the changes to make in the Web page to receive responses; otherwise the dialogues are unknown to the user.

Ajax requests are made asynchronously: the Web browser continues to run JavaScript program while the application is part he does not expect the response sent by the web server and the user can continue to perform manipulations during this time.

1.4. Social Medias

According to Wikipedia, Social media is media using highly accessible communication technologies to facilitate social interaction.

Social networks are groups of individuals or organizations that discuss, speak, and interact with each other. They share opinions, ideas or content. On the web, social networks are greatly favoured by the advent of platforms such as Facebook, Twitter, YouTube and Linked In.

In fact, there are hundreds of platforms that create community between people and / or businesses. This is why it is important, before embarking on your "conquest" of the web, to determine where your customers, so by extension what platforms to use.

Here, we talk about networks like Facebook (with over 1 billion users to date, this is the best known and most popular). They allow finding the knowledge, family members or friends. We can exchange photos and videos, chat with them, organize events.

They allow to share and stream music or videos. Among the best known include among others as YouTube and MySpace (who just a facelift). These are portals that can among others allow artists to make them known.

Linked In is a good example. This network allows you to connect with colleagues in offices, suppliers, business partners or potential employers. By creating a profile, they can include their resume and accomplishments. We can also interact by discussing our industry.

Social networks today represent the majority of exchanges messages in the world through internet outpacing mail service. A web portal can also out of respect be compared to social media because many times offered by web portals services make them social media forums like the service..

1.5. Web portals

Portal sites are websites whose primary purpose is to provide users with resources and services related to a theme, a profession, a geographic area or community.

Resources may be links to other sites reference discussion forums or blogs, but can also consist of editorial content specific to the portal.

These services can be of different types: specialized search engine, email, personalized weather, calculation tools.

A web portal is most often one specially-designed web page which brings information together from diverse sources in a uniform way. Usually, each information source gets its dedicated area on the page for displaying information (a portlet); often, the user can configure which ones to display. Variants of portals include mash ups and intranet "dashboards" for executives and managers. The extent to which content is displayed in a "uniform way" may depend on the intended user and the intended purpose, as well as the diversity of the content. Very often design emphasis is on a certain "metaphor" for configuring and customizing the presentation of the content and the chosen implementation framework and/or code libraries. In addition, the role of the user in an organization may determine which content can be added to the portal or deleted from the portal configuration.

A portal may use a search engine API to permit users to search intranet content as opposed to extranet content by restricting which domains may be searched. Apart from this common search engines feature, web portals may offer other services such as e-mail, news, stock quotes, information from databases and even entertainment content. Portals provide a way for enterprises and organizations to provide a consistent look and feel with access control and procedures for multiple applications and databases, which otherwise would have been different web entities at various URLs. The features available may be restricted by whether access is by an authorized and authenticated user (employee, member) or an anonymous site visitor.

Examples of early public web portals were AOL, Excite, Netvibes, iGoogle, MSN, Naver, Lycos, Indiatimes, Rediff, and Yahoo. See for example, the "My Yahoo!" feature of Yahoo which may have inspired such features as the later Google "iGoogle". The configurable side-panels of, for example, the modern Opera browser and the option of "Speed Dial" pages by most browsers continue to reflect the earlier "portal" metaphor.

1.5.1. Types of web portals

A personal portal is a web page at a web site on the World Wide Web or a local HTML home page including JavaScript and perhaps running in a modified web browser. A personal portal typically provides personalized capabilities to its visitors or its local user, providing a pathway to other content. It may be designed to use distributed applications, different numbers and types of middleware and hardware to provide services from a number of different sources and may run on a non-standard local web server. In addition, business portals can be designed for sharing and collaboration in workplaces. A further business-driven requirement of portals is that the content be presented on multiple platforms such as personal computers, personal digital assistants (PDAs), and cell phones/mobile phone/mobile phones. Information, news, and updates are examples of content that would be delivered through such a portal. Personal portals can be related to any specific topic such as providing friend information on a social network or providing links to outside content that may help others beyond your reach of services. Portals are not limited to simply providing links. Outside of business intracet user, very often simpler portals become replaced with richer mash up designs. Within enterprises, early portals were often replaced by much more powerful "dashboard" designs. Some also have relied on newer protocols such as some version of RSS aggregation and may or may not involve some degree of web harvesting.

At the end of the dot-com boom in the 1990s, many governments had already committed to creating portal sites for their citizens. These included primary portals to the governments as well as portals developed for specific audiences. Example of government web portal in Cameroon may include: the web portal of the government in relation to the service of the prime minister ( www.spm.gov.cm); the web portal of the presidency of the republic of Cameroon.

Cultural portal aggregate digitized cultural collections of galleries, libraries archives and museums. This type of portals provides a point of access to invisible web cultural content that may not be indexed by standard search engines. Digitized collections can include books, artworks, photography, journals, newspapers, music, sound recordings, film, maps, diaries and letters, and archived websites as well as the descriptive metadata associated with each type of cultural work. These portals are usually based around a specific national or regional grouping of institutions. Examples of cultural portals include: Cameroun-Plus ( www.cameroun-plus.com) a portal for touristic information.

Corporate intranets became common during the 1990s. As intranets grew in size and complexity, webmasters were faced with increasing content and user management challenges. A consolidated view of company information was judged insufficient; users wanted personalization and customization. Webmasters, if skilled enough, were able to offer some capabilities, but for the most part ended up driving users away from using the intranet.

Many companies began to offer tools to help webmasters manage their data, applications and information more easily, and through personalized views. Portal solutions can also include workflow management, collaboration between work groups, and policy-managed content publication. Most can allow internal and external access to specific corporate information using secure authentication or single sign-on.

Java Specification Request (JSR168, 2001), standards allow the interoperability of portlets across different portal platforms. These standards allow portal developers, administrators and consumers to integrate standards-based portals and portlets across a variety of vendor solutions.

The concept of content aggregation seems to still gain momentum and portal solution will likely continue to evolve significantly over the next few years. The Gartner Group predicts generation 8 portals to expand on the Business Mashups concept of delivering a variety of information, tools, applications and access points through a single mechanism.

With the increase in user generated content, disparate data silos, and file formats, information architects and taxonomist will be required to allow users the ability to tag (classify) the data. This will ultimately cause a ripple effect where users will also be generating ad hoc navigation and information flows.

Corporate Portals may also offer customers & employees self-service opportunities. Examples could be the portal of Orange Cameroon ( www.orange.cm) or the portal of MTN Cameroon.

Also known as stock-share portals, stock market portals or stock exchange portals are web-based applications that facilitates the process of informing the share-holders with substantial online data such as the latest price, ask/bids, the latest News, reports and announcements. Some stock portals use online gateways through a central depository system (CDS) for the visitors (ram) to buy or sell their shares or manage their portfolio.

A tender portal is a gateway for government suppliers to bid on providing goods and services. Tender portals allow users to search, modify, submit, review and archive data in order to provide a complete online tendering process.

Hosted web portals gained popularity and a number of companies began offering them as a hosted service. The hosted portal market fundamentally changed the composition of portals. In many ways they served simply as a tool for publishing information instead of the loftier goals of integrating legacy applications or presenting correlated data from distributed databases. The early hosted portal companies such as Hyperoffice.com or the now defunct InternetPortal.com focused on collaboration and scheduling in addition to the distribution of corporate data. As hosted web portals have risen in popularity their feature set has grown to include hosted databases, document management, email, discussion forums and more. Hosted portals automatically personalize the content generated from their modules to provide a personalized experience to their users. In this regard they have remained true to the original goals of the earlier corporate web portals. Emerging new classes of internet portals called Cloud Portals are showcasing the power of API (Application Programming Interface) rich software systems leveraging SOA (service oriented architecture, web services, and custom data exchange) to accommodate machine to machine interaction creating a more fluid user experience for connecting users spanning multiple domains during a given "session". Leading cloud portals like Nubifer Cloud Portal showcase what is possible using Enterprise Mash up and web Service integration approaches to building cloud portals.

A number of portals have come about which are specific to the particular domain, offering access to related companies and services; a prime example of this trend would be the growth in property portals that give access to services such as estate agents, removal firm, and solicitors that offer conveyance. Along the same lines, industry-specific news and information portals have appeared, such as the clinical trials-specific portal.

2. SUSTAINABLE DEVELOPMENT AND ICT

Promoted by some as the ideal solution to all environmental problems, criticized by others as a growing source of concern and negative impacts on our planet, ICT and their relation to sustainable development is a subject that leaves no one indifferent.

Thus it is quite undeniable that ICT has many negative impacts on our planet and it is mainly the energy consumption (Datacenter are big energy consumers), the production of difficult to recycle electronic waste. However it is equally undeniable that the contribution of ICT to sustainable development places it as a leading actor. Indeed technological innovations that come one after the other changing our ways of working, exchange, access to entertainment. This contribution can be enjoyed on many levels corresponding to a crossover approach to the pillars of sustainable development:

· At the level of governance: ICT is widely used at this stage as the decision support tools. Many software are used to provide analysis and even future projections.

· The establishment of competence networks: this can be seen for example as the capacity offered through many internet web portal to bring together experts in various fields to promote the exchange of expertise;

· From the day before the first application of ICT (information systems) to sustainable development has led to the search for information to better understand the ins and outs of sustainable development.

This means that this work is placed straight on the objectives of ICT facing sustainable development. Because in addition to promoting sustainable development, it also puts the computer science forward, where the concept of "green IT".

3. LITERATURE REVIEW

This section will consider the various works that focused on building a web platform so that we can learn from them, is to say that a critical analysis is made.

Patrice Zangue GOGUIA (2013), designed and implemented a communication platform for Cameroonian teachers. This means that he has developed a web application to facilitate collaboration between teachers regardless of their place of residence. This work is based on information gathered from school activities, as well as a methodology and a common approach to web applications (UML) to achieve a web application, a platform equipped with a forum, a messaging service, and a database.

Prince MUJUMBE SALAMA (2012), designed and developed a web portal for all the Burundian actors (businessmen, farmers, lawyers and others). His work aims to promote dialogue between actors from different horizons allowing a cultural mix and a stronger national cohesion. He made use of the UML modeling method and numerous programming languages like PHP. However, building a portal to a broad range of people and offering a large amount of resources may prove to be in use to be a failure.

The «Portail du DéveloppementDurable»of the BNF (BibliothèqueNationale de France) is a portal that shows its functions just the way forward in building the portal that will be ours, by presenting personalized functions such as internal research. Let us recognize that many of the functions referred to our portal are not included.

CONCLUSION

The chapter takes an end allowed us to highlight the shapes of the subject of ours broadening our scope of knowledge of web applications and the relationship between sustainable development and ICT. This means that the subject is not ex nihilo and belongs to its time and the part that was so well illustrated advantage will help us in refining our research methodology as well as the selection of tools that will help us.

CHAPTER THREE:RESEARCH METHODOLOGY AND MATERIALS USED

INTRODUCTION

Any research necessarily involves several steps. This means that once the preliminary investigations have been conducted, it is to choose a methodology that will drive the project to completion. Thus, the abundance of computer methods demands a rigorous examination of all possible choices. Also, in the context of this application this chapter fits like a logical continuation of the above will determine its content.

1. WEB APPLICATION ARCHITECTURE

In computing, the architecturerefers to the overall structure inherent in a system, the organization of the different elements of the system (software and/or hardware and/or humans and/or information) and relations between elements. The Web architecture is the branch of the information system architecture that is interested in web applications. There are currently a large number of architectures used for the web.

1.1. The 2tiers architecture

It is composed of two parts, a client and a server. This architecture can also be represented with a database server (DBMS).

In this type of architecture, the customer assumes presentation tasks and communicates only with the application server. This type of architecture can be developed very quickly depending on the complexity of the project. There are a very large number of development languages and tools for 2tiers architectures.

From the standpoint of convenience, the problem of scalability, maintenance and implementation in complex projects must be taken into account.

1.2. The 3-tiers architecture

· The presentation layer (top level) often called HMI (Human Machine Interface) is the visible and interactive part. This part is designed for the Web in HTML usually with JavaScript, Flash.

· The business layer (second-level) is the functional part of the application. The operations to be performed, the data access functions and treatments are available to users and raised by their requests. To provide these services, it sometimes relies on the data access layer and in turn refers to the presentation layer the results it has calculated.

· The last layer (third level) manages access to system data. These data can be stored on the same system (files, XML files, databases, images ...) or other systems. Data access is transparent to the business layer and is the only concern of the data access layer.

1.3. The n-tiers architecture

N-tiers architecture has been designed to overcome the limitations of 3-tiers architectures and develop powerful applications and simple to maintain. From a theoretical point of view, this architecture allows to solve the following problems:

One possible definition of this type of architecture is: a 3tiers architecture in which the data processing (data access layer or middleware) itself contains several layers multiplying the third.

1.4. The MVC architecture

The MVC architecture proposed by Sun is the server-side Web development solution that separates the logical part / business part of the presentation in a Web application. This is an essential part of development projects because it allows the team to work separately (each has its files, software development and its components).

This architecture has its origins in the SmallTalk language early 1980. The main objective is to divide the application into three distinct parts: the model, view and controller.

2. MODULES OF APPLICATION WEB SITE

In a comprehensive way, the modules can be defined as the constituent parts of a system. In terms of IT, a program usually consists of a set of sub-programs (modules) that form a whole. Web applications are no exception to the rule, and more dynamic web site pages more likely it is to have modules. Therefore, our portal will also have many modules that are consistent with its objectives.

3. RESEARCH DESIGN

Here, reference is made to the conceptual framework in which the desired project is completed. Thus, the objectives have already been located, however, point out that the data used in the whole process are secondary data. The major source of information is without doubt the internet.

4. ANALYSIS METHODS

4.1. Object Oriented Methods

Object modeling is to create a computer model of the user's system (a computer system). This model can bring both elements of the real world concepts or ideas around business or field which will be part of the system.

4.1.1. UML method

UML (Unified Modeling Language) is a graphical modeling language based on pictograms. He appeared in the world of software engineering, as part of the "object-oriented design." Commonly used in software projects, it can be applied to all kinds of systems are not limited to the IT sector.

4.1.1.1. Advantages

· The standardization of object concepts, which have clear benefits in terms of computer applications.

4.1.1.2. Limits

· A large additional work is necessary to synchronize the code with the diagrams

4.1.2. UP method

Unified Process (UP) is a management method of the life cycle of software development and therefore, for the object-oriented software. This is a generic method, iterative and incremental.

4.1.2.1. Advantages

It is adapted to the work context, the needs of the user, the library reuse opportunities or "bricks" preexisting.

UP method has a bidirectional architecture that minimizes the risks against the grain to the needs and the risk of infinite developments, indefinite, unclear or incomplete: Here the user can correct itself on prototypes, turn that takes development. From the beginning of operations, tangible results are obtained even if they are only prototypical.

4.1.2.2. Limits

4.2. Functional methods

4.2.1. SADT method

Structured Analysis and Design Technic (SADT) is a method of American origin, developed in 1977, it spread in the late 1980s as one of the standard graphic description of a complex system down by functional analysis, that is to say that the analysis travels from the general to the specific and detailed. SADT is a systemic approach to modeling a complex system or operating process.

4.2.1.1. Advantages

· Structure hierarchical level by allowing clarification and analytical breakdown of the complexity of a system.

4.2.1.2. Limits

4.2.2. MERISE method

MERISE is a French acronym, «Méthode de Recherche Informatique pour les Systèmes d'Entreprise». It is a method of analysis, design and IT project management. MERISE has been widely used in the 1970s and 1980s to the massive computerization of organizations

4.2.2.1. Advantages

MERISE method has as undeniable advantage of allowing a clear definition of the overall information system and to define correctly the perimeter.

The strength of the MERISE method is to structure the needs of decision makers in a simple and understandable way. MERISE improves communication between different actors in the development process. This method, thanks to its models, oversees the project and thereby protects the speakers of a possible development irrelevant.

Follow this intellectual journey may also help the company to better know, understand each other better and thus communicate better.

4.2.2.2. Limits

MERISE method is ill-suited to distributed environments where multiple external applications to a domain come interact with the application to model. Moreover, it is not able to model the semantic identifiable information (documents).

4.3. Choose of a method

MERISE should definitely match the research work of ours as it is true that his grip does not require a lot of time as its application to the project given the constraints and requirements are ours.

5. MERISE STEPS

5.1. MERISE levels

5.1.1. Conceptual level

The conceptual level is to design the SI disregarding all technical and organizational constraints and these both in terms of data treatment.

The conceptual level answers the question What? (On what to do, what with data).

5.1.2. Organizational level

The organizational level's mission is to integrate the analysis criteria related to the organization studied. The organizational level will define the notions of temporality, chronology of operations of unity of place, will define the workstations, access to data bases.

5.1.3. Logical level

Logic is independent of hardware, programming languages and data management. This is the answer to the question What with?

5.1.4. Physical level

The physical level defines the actual organization (physical) of data. It provides technical solutions, such methods of storage and access to information. This is the answer to the question What?

5.2. Data dictionary

The data dictionary is a document that allows identifying, classifying and sorting all the information (data) collected during interviews or study the documents. The dictionary can be more or less elaborate depending on the desired level of granularity. The dictionary data generally includes the following information:

· The name of the data: the name that will be used to represent the data in the database and the computer program

· The type of data: this field represents the data type to use for the backup of each element;

· Nature: This setting will help in the representation of data in the database;

· Size: the representation of the maximum amount of data that will contain every element;

On our portal for sustainable development, we have the following data dictionary:

N0	Name	Description	Type	Nature	Size	Observation
1	Doc_id	Document id	Int	N	10	Obligatory
2	Doc_name	Document name	Varchar	AN	255	Obligatory
3	Doc_description	Document description	Varchar	AN	255	Facultative
4	Doc_path	Document path	Varchar	AN	255	Obligatory
5	Link_id	Link id	Int	N	10	Obligatory
6	Link_name	Link name	Varchar	AN	255	Obligatory
7	Link_description	Link description	Varchar	AN	255	Facultative
8	Link_url	Link url	Varchar	AN	255	Obligatory
9	Art_id	Article id	Int	N	10	Obligatory
10	Art_title	Artcicle title	Varchar	AN	100	Obligatory
11	Art_content	Article content	Text	AN		Obligatory
12	Art_author	Article author	Varchar	AN	255	Facultative
13	Art_date	Article publication date	Date	y/m/d		Facultative
14	Art_media	Article media file	Varchar	AN	255	Facultative
15	Sug_id	Suggested content id	Int	N	10	Obligatory
16	Sug_type	Suggested content type	Varchar	AN	255	Obligatory
17	Sug_author	Suggested content author	Varchar	AN	255	Obligatory
18	Sug_cont	Suggested content contain	Text	AN		Obligatory
19	Sug_date	Suggested content date	Date	Y/M/D		Facultative
20	Sug_media	Suggested contentmedia file	Varchar	AN	100	Facultative
21	Mess_id	Message id	Int	N	10	Obligatory
22	Mess_send	Message sender	Int	N	10	Obligatory
23	Mess_recei	Message receiver	Int	N	10	Obligatory
25	Mess_cont	Message content	Text	AN		Obligatory
26	Mess_date	Message date	Date	Y/M/D		Facultative
27	User_id	User id	Int	N	10	Obligatory
28	User_name	User name	Varchar	AN	100	Obligatory
29	User_loc	User location	Varchar	AN	50	Facultative
30	User_prof	User proffession	Varchar	AN	50	Facultative
31	Top_id	Topic id	Int	N	10	Obligatory
32	Top_title	Topic title	Varchar	AN	100	Obligatory
33	Top_descr	Topic description	Varchar	AN	255	Obligatory
34	Top_sub_nbr	Number of subjects	Int	N	10	Facultative
35	Sub_id	Subject id	Int	N	10	Obligatory
36	Sub_title	Subject title	Varchar	AN	100	Obligatory
37	Sub_descr	Subject description	Varchar	AN	255	Obligatory
38	Com_id	Comment id	Int	N	10	Obligatory
39	Com_author	Comment author	Varchar	AN	100	Obligatory
40	Com_cont	Coment contain	Text	AN		Obligatory
41	Com_date	Comment date	date	AN		Facultative

5.3. The Data Conceptual Model (DCM)

The DCM is based on entity concepts and association and on the concepts of relationships. Graphing, simple and accessible, allowing a non-IT to participate in its development. The basic elements of a conceptual data model are:

5.3.1. Entities

The entity is defined as a management object considered of interest to represent the activity model (eg user entity) and each entity carries one or more simple properties, including one called atomic, unique and discriminant is designated as an identifier.

5.3.2. Properties

The properties are the basic information of the information system. They are essential and basic information.

5.3.3. Occurrence

5.3.4. Identifier

One of these properties has a specific role, it is also known as the key identifier. The identifier is used to find a safe and unique way all the properties involved in the entity. We must find or invent a property when its value is known allows the knowledge of all the values attached to it formally.

5.3.5. Associations and Cardinalities

The association is a semantic link between one or more entities: the association can be reflexive, preferably binary, and ternary sometimes or even higher dimension. It may also be a carrier of one or more properties.

The association is enriched by the notion of cardinality, it indicates the minimum and maximum number of times any occurrence of an entity can participate in an association, and we can have:

- 0 if an occurrence of the entity may exist while not interfering in any occurrence of the association

- 1 if an occurrence of the entity can exist only if it occurs in at least one occurrence of the association

- 1 if an occurrence of the entity cannot be involved in more than one occurrence of the association

- N whether an instance of the entity cannot be involved in more than one occurrence of the association

5.3.6. Normalisation rules

This is about the rules to be observed the relationship entity association to be valid.

· Normalisation of names

The name of an entity, his attributes and the name of the association between the entities must be unique. Two entities can't have the same attribute name.

· Normalisation of identifier

A good identifier should avoid too much attributes, and should have the lesser number of characters as possible.

· Normalisation of attributes

It is recommended to avoid entities with too many attributes by replacing those attributes with associations.

· Normalisation of attributes of associations

The associations attributes must directly depend of the identifiers of the table that the association link.

· Normalisation of associations

Associations should be materialise with verb in the infinitive form or eventually in the passive form.

5.3.6.1. First Normal Form (1NF)

5.3.6.2. Second Normal Form (2NF)

In other words, any property of the relationship must depend entirely of the key.

5.3.6.3. Third Normal Form (3NF)

- If all functional dependencies on the key are direct (if there is no transitive functional dependencies between non-key attributes).

In other words, all of the attributes do not belong to the key does not depend on a non-key attribute.

5.3.7. Complete CDM

Following the rules stated above, we developed the conceptual model of the following data:

5.4. Data Logical Model (DLM)

The DLM is the normal result of MERISE process. Its purpose is to bring us closer to the physical model. For this, we start from the Conceptual Data Model and the relationships we remove it within certain pre-established rules.

5.4.1. Definition of concepts

The LDM provides technical vocabulary again that it is important to understand well.

5.4.1.1. Tables, columns and rows

So that was an entity Data Conceptual Model is a table in the DLM. Thus this table is organized in line or column and each column represents the fields of the table and each line represents the values for each field.

5.4.1.2. Primary and foreign keys of each table

The identifier that had the DCM, DLM is the primary key which can be recognized by its underlining. Also a table can contain the primary key of another table that at that moment becomes a foreign key. Which foreign key is symbolized by a sharp before his name. Thus:

5.4.2. From DCD to Data Logical Relational Data Model (DLRM) rules

As mentioned above, the passage of the DCM to DLRM is purely mechanical, simply meet and set some rules.

5.4.2.1. Entity and table

Each entity becomes a table and therefore, the identifier becomes the primary key, the properties of the entity become the table attributes.

5.4.2.2. Binary relation with cardinalities (X,1) - (X,n), X=0 or X=1

The entity type cardinality 1.1 or 0.1 absorbs the identifier of the strongest entity (0, n or 1, n). This identifier is then called the foreign key.

5.4.2.3. Binary relation with the cardinalities (X,n) - (X,n), X=0 or X=1

Where n is the maximum cardinality of both sides of the relationship it becomes entity and absorbs identifiers each related entity. Without enough IDs are the new key of the entity. This new key is formed by the concatenation of the foreign key related entities.

5.5. From Data Logical Relational Model (DLRD) to Data Physical Model (DPM)

Building the Physical Data Model is to transform the Logical Data Model into a series of relationships. This step completes the data processing process. The implementation of the databases can be performed optimally.

5.6. Data Physical Model

The Data Physical Model is the final step in the data management process MERISE method. All analysis was carried out upstream, most of the work of reflection was framed by the conceptual model, and the transition to the physical model is a mere formality.

6. MATERIALS USED

The actual conduct of this project required the involvement of numerous tools both hardware and software whose role will be declined as well.

6.1. Software

This refers to a list of software that helped in the construction of the project and the various programming languages used.

6.1.1. HTML

The Hypertext Markup Language, HTML generally short, is the data format designed to display web pages. It is a markup language that allows writing of hypertext, hence its name. HTML also allows structuring semantically and formatting the page content, to include multimedia resources including images, input forms, and programmable elements such as applets. It allows the creation of interoperable documents with varied amenities manner consistent with web accessibility requirements. It is often used in conjunction with programming languages (JavaScript) and presentation formats (cascading style sheets). HTML is originally derived from the Standard Generalized Markup Language (SGML).

In this work, it is the HTML 5 to be used, this version offers new attributes and tags and new specifications.

6.1.2. CSS: Bootstrap framework

CSS (Cascading Style Sheets) is a computer language used to describe the presentation of HTML and XML documents. The standard defines CSS are published by the World Wide Web Consortium (W3C). Introduced in mid-1990, CSS is commonly used in web design and well supported by web browsers in the 2000s.

Note that until today, many CSS features are incompatible for some browsers. And it is the same for the CSS3 version that is used in this project, even some specifications have not yet been integrated in most browsers.

Thus, in order to make the development easy, we associate the Bootstrap framework, which is a CSS framework put in place by twitter to help in the building of websites. Bootstrap associate JQuery to involve more performance.

6.1.3. JavaScript

According to Wikipedia, JavaScript is a scripting programming language mainly used in interactive web pages but also on the server side. It is an object oriented language by the prototype, that is to say that the basic language and key interfaces are provided by objects that are instances of classes, but which are each equipped with builders for generating their properties, including a prototype property that allows to generate custom objects heirs.

JavaScript code can be integrated directly into Web pages, to be executed on the client. This is when the web browser that supports the execution of these programs called scripts.

Generally, JavaScript is used to control the data entered in HTML forms, or interact with the HTML document via the Document Object Model interface provided by the browser (this is sometimes called dynamic HTML or DHTML). It is also used to perform dynamic services, sometimes pointless, strictly cosmetic or for ergonomic purposes.

JavaScript is not limited to the handling of HTML documents and can be used to manipulate documents SVG, XUL, and other XML dialects. On the contrary, the possibilities of language are seen increased through new technologies (AJAX, JSON) and many libraries (including JQuery, SeaHorse).

6.1.3.1. AJAX

According to the Web Dictionary, AJAX means software architecture for creating pages and to interact with the user web applications and / or other applications without the need to reload page in the web browser client. This means AJAX relies on technologies present in the different web browsers, including JavaScript and XML, which are included in the acronym AJAX "Asynchronous JavaScript and XML".

AJAX does not bring anything new compared to these technologies, most of which have existed for many years. However it offers a method to use them together to create dynamic applications executed by browsers.

6.1.3.2. JQuery

JQuery JavaScript Library is a free, multi-platform created to facilitate client-side scripting in the HTML code of web1 pages. The first version was launched in January 2006 by John Resig.

6.1.4. PHP

PHP acronym originally meant Personal Home Page. For RasmusLerdorf, the author of what became Scripting embeddable server side throughout XHTML document that we know, this meant adding some functionality to their personal pages. PHP stands for PHP Hypertext Preprocessor today because it refers to an XHTML document browser built by the script engine Zend Engine 2 PHP. It allows creating dynamic and interactive Web pages.

PHP's strengths are firstly it is free and allows you to create powerful web applications, on the other hand PHP since version 5 is object oriented. It is this version that is used in this work.

Although sometimes attributed to him the characteristic of being low in terms of safety, PHP has a powerful community, and served to the world renowned building sites like Facebook.

6.1.5. SQL

Structured Query Language (SQL) is a standard computer language used to perform operations on databases. Created in 1974, the SQL is standardized since 1986, the language is recognized by the vast majority of database management systems.

The SQL data manipulation language section allows you to search, add, modify or delete data in databases. Coupled to the PHP SQL, it allows the web application to interact with the database.

In addition to the data manipulation language, the language of data definition to create, edit and organize data in the database, the transaction control language section allows you to start and finish the transaction, and data control language section to allow or deny access to certain data to certain people.

6.1.6. WampServer

WampServer is a web development platform WAMP type, for operating locally (without connecting to an external server) PHP scripts. WampServer is not in itself a software, but an environment with two servers (Apache and MySQL), a script interpreter (PHP) and PhpMyAdmin to administer Web MySQL databases.

6.1.7. Aptana Studio

Aptana Studio is an integrated development environment oriented web, multi-platform and open-source. It makes writing code by providing entry aids for JavaScript, HTML, CSS, PHP and Python.

Aptana is available standalone or plugin in its original environment: Eclipse. Aptana has several plugins to program for languages / platforms like specific RadRails, Adobe Air and many others.

6.1.8. Web browsers

A web browser is a software designed to browse the web. Technically, it is at least an HTTP client. These are complex and evolving software, mainly in security, as new viruses, spyware and other malicious scripts continue to emerge, but also in terms of functionality because of new standards or standards revisions see regularly updated.

The main function of a web browser is to allow the consultation information available ("resource" in the Web terminology) on the World Wide Web. The main stages of the consultation of a resource are:

· The user gives to the web browser the web address resource to consult. There are three ways to give a web address:

- Choose a resource in the list of favorites (or bookmark this page or bookmark), knowing that every favorite is associated a web address;

· The browser connects to the web server hosting the resource referred and downloads. The communication protocol generally used is http.

· Rendering engine of the browser treats this resource, downloads any associated resources and displays the result on the user's screen.

Web browsers will be fully customary in the process of developing this web application for both tests for debugging. And those used are the two most popular browsers such as Google Chrome and Mozilla Firefox.

6.1.9. Adobe Photoshop

Photoshop is an editing software, processing and computer aided drafting edited by Adobe and owned for quite some years after Adobe CS. It is mainly used for processing digital photographs, but also serves to create images from scratch. He works mainly on raster images because the images are made up of a grid of points called pixels (for Picture Element). The interest of these images is to reproduce subtle gradations of color.

6.1.10. Power designer

PowerDesigner is a collaborative enterprise modeling tool produced by Sybase. PowerDesigner runs under Microsoft Windows as a native application, and runs under Eclipse through a plugin. PowerDesigner supports model-driven architecture software design. PowerDesigner uses the .pdm file format.

PowerDesigner provides a single modeling environment that brings together the techniques and notations of business process and requirements modeling, data modeling, enterprise architecture modeling, and UML application modeling.

6.2. Hardware

The main unit use is an HP laptop brand (Pavilion dv7) adopts a 2.3GHz AMD Dual Core processor. In 3GB RAM, with a resolution of 17.3 inches.

7. CONCEPTION AND REALIZATION OF THE APPLICATION

7.1. Classification of needs of the future users

A web portal as we have said above is a site that offers a wide range of resource, a gateway to a specific area. Thus the following features to respect our portal we seem to be necessary: a news page, a member area, a messaging system, links to other reference sites, a downloadable document page and the possibility for a member to propose content.

This means that the objectives for users are clear and precise. However, these goals can only be achieved with the completion of a minimum of conditions.

7.1.1. Functional needs

The portal for sustainable development must therefore offer many features to allow the apotheosis of our goals. And these features are:

The user must be able to access the different topics discussed in the forum. It should equally be able to see the comments of website subscribers. However, the ability to comment in the forum is determined by an inscription on the site as well as the ability to exchange private messages with members of the forum. Also registered members on the forum have a visible profile page of the portal only to members. It must also be possible for these members to check out the lists of registered members on the site.

Anyone authenticated on the site gets the opportunity to suggest content. This content can be as much an article, a downloadable document, or a link to share with the users of the site.

These articles that appear year homepage can be read by all site visitors. Although registered members can receive an e-mail alert if they agree.

This page of our platform should offer the ability for users to follow links to better learn about the different areas.

7.1.2. Non-functional needs

7.1.2.1. Quality requirements

Any site that is an attractive must be coherent and non-polluting beauty this in order to retain its members. So we must ensure the usability of the application. So the quality criteria may be stated as follows:

The need to ergonomic websites has even led to the birth of a new discipline in web design, ie its importance to our portal. The ergonomic approach proposes to give the power back to the human being that far from being dependent objects must instead make use. Therefore our platform has to be comfortable, simple, and effective.

The user must be able to receive assistance on certain pages such as those forms so that we ensure that the meaning of each field is clearly understood.

7.1.2.2. Performance requirements

Achieve a proper and sober application is a good thing, but it must at all costs be accompanied by a certain performance. Thus we propose the following objectives:

- The platform must be very reactive, the pages must be able to refresh automatically;

7.2. Functional specifications

Of course the platform must be accompanied by a database. Which database should be updated automatically from the forms of the portal. And save each item must contain all necessary references to a possible recovery to be displayed on a page of the site then be modified or deleted view of the database. This applies to articles, documents and links.

The personal data of users will be protected just as the transmission of data to the database.

7.3. The software life cycle

Laurent AUDIBERG (2008) defines the life cycle of software as all stages of software development, from conception to its demise. The goal of such a division is to define intermediate milestones for validation of software development, that is to say, the compliance of the software with the expressed needs, and verification of the development process, it is -to say the appropriateness of the methods implemented.

The origin of this division comes from the fact that the errors have a higher cost as much as they are detected late in the implementation process. The life cycle can detect errors earlier and thus to control the quality of the software, the time of its implementation and the associated costs.

- Goal Setting: This step is to define the purpose of the project and its inclusion in a comprehensive strategy.

- Needs analysis and feasibility: that is to say the phrase, collecting and formalizing requirements of the applicant (the client) and the set of constraints, and estimate the feasibility of these requirements.

- Specifications and overall design: This is the development of specifications of the general architecture of the software.

- Detailed Design: This step is to clearly define each subset of the software.

- Coding (implementation or programming): it is the translation into a programming language features defined during design phases.

- Unit Testing: They allow you to individually verify that each subset of the software is implemented according to specifications.

- Integration: The objective is to ensure that the interfacing of different components (modules) of the software. It is the subject of integration testing in a document.

- Qualification (or recipe): That is to say, the verification of compliance software to the initial specifications.

- Documentation: It aims to produce the information needed to use the software and further developments.

- Maintenance: It includes all corrective actions (corrective maintenance) and scalable (scalable maintenance) on the software.

The sequence and the presence of each of these activities in the life cycle depend on the choice of a life cycle model between the client and the development team. The life cycle can take into account the technical, organizational and human aspects.

7.4. Structure of the web application

Taking into account the objectives of our platform, architecture and the examples set by other portals of the same type, we have set up this structure.

8. PARTIAL CONCLUSION

So we come to the end of this chapter that wants to be the one through which all design activities end and gives the way forward for the construction of the application.

In this chapter we will using the screen capture strive to show the results obtained followed possibly comment.

1. HOMEPAGE

The home page presents the hyperlink functions through images leading to the main parts of our platform. However some pages are only accessible if the user is identified and also if and only if it is the administrator

2. CONNECTION / DISCONNECTION

The connection is an essential aspect of our portal since it will regulate access and use of certain parts of our platform. So on the home page is placed a login form available below with the link to open the registration page. The figure below show the connection form and the link to the registration page

The connection ask to the user to enter his login and password followed by enter.

2.1. Subscribe

For users who want to enjoy all the benefits, enrolment is a major step and it is through the following form:

This form illustrated by the figure ask the user to enter some information like his name, gender, location, picture and to choose a pseudo and a password to be used next time for login. In case of failure in filling the form that account will not be created.

2.2. Disconnection

Once connected, the space formally reserved to the login form is now for the presentation of the current user's photo and his ID while providing a logout button. This is illustrated by the figure bellow

3. CONSULT PAGES

These are pages that allow you to either view the contents of the portal, or to download the documents available or to follow the available links to other sites operating in the same field.

3.1. Link page

The page is made of three main parts: category, link and description. Therefore, by clicking on the link the user is automatically bring on another page.

3.2. Article page

This page show the actuality of sustainable development in our country trough text accompany by picture or eventually video.

3.3. Document page

Here we have a collection of document related to our topic which can then be downloaded illustrated by the figure below.

The library can contain document which can be downloaded through the download button.

4. SEARCH

On our platform, we have both sought an engine that is internal and the other external.

4.1. Search in the website

The research here is done in the items available in the database. The key words are entered in the top search bar and the results appear as shown in the figure bellow:

The results appear in the aspects of numerated links which can then be followed.

4.2. Google customize search

Google Custom sought is made from the desired form and the results appear in a Google window.

5. PROPOSE CONTENT AND GENERAL ADMINISTRATION

It is here given the opportunity to the administrator as the single user to contribute to the updating of the portal. The forms are the same, only difference the content offered by a user waits for the validation of the administrator to be visible.

5.1. Link

To add a new link, the user must provide a title, link, description, and choose his Cathegory.

5.2. Article

The addition of a new article is done by providing a title, content, author references and the date, then, we can link an image and / or video.

5.3. Document

To add a new document, you must provide a title and a description to this document. The document must not exceed 10MB.

6. FORUM

The forum is organized around central themes divided into topics that can be commented on by users.

6.1. Read topics

6.2. Read subjects

As for the list of topics, this list has two columns, the title and the description of the subject.

6.3. Read and publish comment

7. USER SPACE

7.1. Private Messages

7.1.1. Read messages

As presented in the figure, the user reads his message has the ability to delete or answer to the message.

7.1.2. Send messages

To send a new private message, the form must contain the recipient's pseudo, a title and the content itself.

7.2. Profile

Any user can see his profile page which displays his profile picture and some personal information.

7.3. User list

Here, we have the list of users with their picture, their pseudo and their profession.

8. ADMINISTRATION

8.1. Forum administration

8.2. Users administration

1. SUMMARY OF FINDINGS

This chapter comes as close a logical series which allowed us to develop a web portal for sustainable development.

Thus we have in this work makes use of MERISE for application design, an implementation with PHP5, SQL, JavaScript and HTML. This means that the breakthrough of the Internet in Cameroon provides an unprecedented way to reach the greatest number of persons with minimal effort. Then, starting from an elucidation of the problem from the chapter one to a literature review in chapter two, we come to determine the method and therefore the tools to serve us in building our portal. A Web portal we shared the results in chapter four.

This also means that our objectives were reached. Therefore our platform offers more than an ergonomic interface by associating the following features:

- A news area through articles, which aims to address the needs for clear information.

- An electronic library from which can be downloaded documents previously posted by the administrator;

- A section containing links leading to web site offering complementary services to our platform;

- A space for discussion or forum that aims to be a place to share ideas and information about many topics;

- Also, our application has a user space for those who have registered and are connected. They can exchange private messages while consulting the directory of registered members of the portal. Our aim was to engage maximum users of our application warrants the ability given to them to offer content being articles, links or even documents.

- All this is happening precisely the watchful eye of the director in his task may decide to give a simple moderator member status to assist in the forum admin.

2. DIFFICULTIESENCOUNTERED

As in any human endeavor, difficulties were encountered at several stages of the study. The most important are related to the delimitation of the subject, the choice of analyses method, the choice of tools as well as the graphic design of the application.

Sustainable development is a huge topic; the choice of activities to implement on our portal was not easy.

Also, there is a multitude of web application analyses approach and to sort out all these methods is a thorough exercise as the selection of one of them.

Web programming being in constant evolution, select the tools becomes a rather difficult task because everyone has these benefits and disadvantages that must be taken into account.

Graphic design meanwhile proved a little more difficult in regard to the choice of colors, the arrangement of elements of the application in order to make an ergonomic application.

3. RECOMMENDATIONS

· The security of this application remains one of the problems we have tried to include it in different parts of the application like in form validation, in the access rights. Also security is included in displaying data received from users (login, password).

· The functionalities of our application are complete according to our objectives. However, many other tools could be incorporated in this application to make it better like the use of phones.

· In terms of technique and technology employed, these could equally be improved with: for the technique, a completely MVC (Model View Controller) could be usedand for the technology a better integration of AJAX.

4. SUGGESTIONS FOR FURTHER STUDIES

While we we're trying to give this application a much larger it is, however, appropriate to point out some shortcomings that could be addressed in future studies. Thus we can highlight:

- The security of the application, security for web applications is of increasing importance especially since our portal provides a user space,then, users store on our platform personal information that should be protected;

- A newsletter system would also be appropriate to alert our users of all news concerning them or whether new private messages. This could of course be improved by a warning system with SMS, and Android phone applications

- Also, the opportunity could be given to users to change their profile which is not yet the case;

- Better integration of AJAX technology which have only been used in some parts of the application.

CONCLUSION

The improved exchange of information between the different actors of sustainable development in our country is what guided this work. Thus, we were concerned to provide students, educators or government authorities as well as expert a tool to exchange, to learn, to communicate using a web portal.

The steps leading to the realization of this web application enabled us to master the best web development tools. So this work was an opportunity for us to put into practice the knowledge acquired in application design as web materials regarding the approach tools. So our programming skills have been increased including server side programming with PHP as client side interactivity with JQuery (JavaScript Framework). However, this application can't alone be the solution to a more global problem which is a sustainable development for our country.

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APPENDICES

`cathegory` enum('formation','etat','ong','international','autre') COLLATE utf8_bin NOT NULL DEFAULT 'autre',

ADD CONSTRAINT `comments_ibfk_1` FOREIGN KEY (`id_sujet`) REFERENCES `sujets` (`id_sujet`) ON DELETE CASCADE ON UPDATE CASCADE;

ADD CONSTRAINT `messages_ibfk_1` FOREIGN KEY (`sender_id`) REFERENCES `users` (`id`),

ADD CONSTRAINT `messages_ibfk_2` FOREIGN KEY (`receiver_id`) REFERENCES `users` (`id`);

ADD CONSTRAINT `sujets_ibfk_1` FOREIGN KEY (`cat_id`) REFERENCES `categories` (`cat_id`) ON DELETE CASCADE ON UPDATE CASCADE;