ANALYSIS, DEVELOPMENT AND IMPLEMENTATION OF OPEN SOURCE ERP APPLICATIONS

ANALYSIS, DEVELOPMENT AND IMPLEMENTATION

OF OPEN SOURCE ERP APPLICATIONS

Nicolás Serrano Bárcena Javier Santos García Rafael Menéndez Teillet

Ismael Ciordia Vela

Escuela Superior de Ingenieros - Universidad de Navarra [email protected]; [email protected]; [email protected]; [email protected]

SUMMARY

The need for an Enterprise Resource Planning (ERP) information system is widespread among the majority of companies. The current solutions are based on made to measure developments or by adopting standardised solutions. The handicaps inherent in these solutions can be solved with open source applications that allow the tailored development specific to the needs of each company whilst keeping a common base. This paper sets out the points to be taken into account and the features included in one of these developments with the intention of obtaining, at the end, an operative application for a wide range of companies.

Key words: ERP, open source, information technology, XML. INTRODUCTION

The evolution of information systems within companies is seen to affect two main fields: the functionalities that they incorporate and the size of the companies that implement them.

Functionalities included in the systems

On the one hand the number of is or areas of the company covered by management systems has been growing generation after generation of software. The first generation was limited to preparing the salaries, the accounts, the invoicing, tackling these tasks as a mechanical process.

Later, operations management was added: orders or work order or sales predictions are a trigger for a series of operations, this means that the information doesn’t only have to be entered to process the operation but is entered to carry out the operation itself. With this an integration of the various departments within the company is achieved avoiding a duplication of efforts in many of them. A typical example of this integration is business management from the quote to processing the account with the corresponding invoices and once the order has been made up, prepared, sent, invoiced and payment processed

The following generations of information systems incorporate systems that work autonomously such as analytical accounting , production control and planning; this is the era of MRP.

With the current situation the intention is to complete the framework by integrating all internal and external aspects of the company, this includes customers, suppliers and alliances, and all things considered any system that can give or needs information from our company or “information system”, that is to say Enterprise Resource Planning.

On the other hand, information systems which at the beginning were only viable for large companies are becoming more accessible for smaller and smaller companies, incorporating with a certain delay, depending on the size of the company, the functionalities which only the larger companies had a short time before. This incorporations of new functionalities has been accelerating recently both because the companies´ information needs are becoming more immediate and complete and because the software suppliers want to increase their market share. With this in mind, the companies that supply ERPs have been lowering the threshold for invoicing and the number of employees in such a way that in the near future practically any company will have an ERP available.

Showing these two factors graphically (Figure 1), for different sized companies

...)

(

A

>

B

>

C

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Figure 1: Evolution of the functionalities of information systems

From this it can be deduced that the implementation of an ERP system in companies and updating systems to use new technologies is going to be an important task .

Nevertheless, one of the difficulties that the majority of companies find is that the implementation of a system of this type normally exceeds their human and technological resources so that one of the decisions to be made by the company is the way in which they obtain the information system.

Currently the possibilities are: a tailored solution or the implementation of a standard solution. Each of these alternatives presents a series of obstacles and these are the reasons why this article is presented.

CURRENT SOLUCION

As mentioned above, the two solutions currently proposed within a company for the implementation of an ERP is to develop a tailored solution or the incorporation of a standard solution.

Tailored solution s

The alternative developing a tailor solution, means a long development time so that its implementation is delayed with respect to the needs of the company and experience in software development projects has shown that there are always other not insignificant delays. The tailor solution also requires greater resources on the part of the company because although each company has its own peculiarities, there are in fact common processes that are necessary to develop a number of times, so time is lost and money is wasted unnecessarily doing the same thing twice. The project developed will need a maintenance that must be assumed by the company or depend on the contracted external company. It must not to be forgotten that this solution has not been tested in other

Time ERP MRP Manageme Mechanization Functionalities Size A Size B Size C Size ....

companies, consequently the number of errors or obstacles not perceived during its development could be significant .

Standard solution

The standard solution alternative gets round some of these obstacles, but they also give rise to new ones, such as the problem encountered by the company when adapting to the philosophy of the standard application. Although the product can be configured for each company this configuration is only possible within the limits perceived by the company supplying the original. The most normal in these solutions is to have an executable version of the product available which can not be modified by the customer and in many cases the operating system with which it is executed cannot be changed without a change in the operating licence.

The company´s decision between the two alternatives will depend on a series of factors such as the needs that cannot be adapted to a standard application, the time and resources available, confidence in the supplier, etc., but reflect a decision not always apt for the needs of the company.

OPEN SOURCE SOLUTION

One solution for the company would be to have an open source available which can be implemented directly or can carry out the necessary modifications to tailor it according to their needs. Open source means the elimination of restrictions that any traditional software has. This prohibits its copying, distribution, modification, and all things considered everything that would remove the obstacles encountered in the current solutions.

Advantages of open source

With the source open, as the basic files within the application are available, a dependence on the original creator is avoided. This could be because of a change in company policy, company owner or any other factor that modifies the availability of new versions. The open source, can be transferred to new operating systems or carry out the modifications needed without the effort of beginning the task from the start. In addition the designers can access it for its installation, study it, modify it or redistribute it without limits from licences or from the supplying company. This brings freedom, that is not only economic, but also eliminates the obstacles described above.

This theory would seem to have no objections from the company using the ERP application which could obtain a complete application without investing in licences. It seems reasonable to assume that the problem is the existence of an open source and that it can be made. This could have triggered a debate some years ago but today it is enough to refer to the experiences that can be seen on the market to realice that this development is something possible and real.

Open source developments

The main application that exists nowadays is the Linux open source and after years of expectations and a wide variety of experiences it has shown itself to be the best solution in many situations. The fact that it is a highly complex application, as it is an operating system, together with the existence of a large number of other open source developments that have been designed in various fields such as office suites, internet navigators, data bases, server applications, programming tools, etc. show the potential for this type of

ERP in open source

The idea of the proposed project is that of transferring this method of working to ERP applications, a type of application that is as necessary to a company as an operating system to a computer. The existing ERP applications currently used in companies correspond to some of the solutions proposed in the previous section. These standard solutions as they have to cover the demands of any company are converted into applications which are enormous and bring a new obstacle to their implementation because they need the time of specialists, not included in the applications, but in the modules of the same.

As we are dealing with a case of open source from the start, an in depth knowledge of the application is not necessary as the specific problems or that of adding specific instructions within a company is solved easily by tackling the specific problem and not by producing a general solution that is later modified by each company.

Open source features

The way in which the project will be developed is explained in the sections below: in this way we can specify, from the point of view of the company, the advantages that can be obtained with this type of development. The company will have at their disposal a code and therefore an application that has the following features:

• Immediate availability.

• Possibility of modification and tailoring according to their needs.

• Tested and improved through the contribution of other users in the common modules.

• Supplier independence.

• Free distribution.

PROJECT DEVELOPMENT

The development of free software should not be limited to the code although it is the term we refer to when we speak of “open code”. The code is perhaps the most visible part of the development in any informatics project although not the most important in the majority of cases.

Analysis

The open source must begin with the analysis of the application, generating documents both for the user and for development which anybody can have access to so they can achieve the proposed objectives and to attract the largest number of participants in the development and later implementations of the developed application. The current situation is that everybody working in the field of information technology agrees that this analysis is developed in UML (Unified Modelling Language).

The analysis must be carried out not only from the theoretical point of view but also from the implementation of the system in real companies. One of the principal objectives of this analysis is precisely its validation by the user.

Project management

From the size of the project and the variety of its participants comes the critical part of the project, the management of various resources over which there is no complete control such as the control that a company might have over its workers. The experience in other

projects with open source, projects and business management must establish the norms and methods to maximise, optimise and motivate the available resources.

Implementation

Another important task that must not be left for a later phase is the use of the results obtained, that is to say, achieving the implementation of the developed applications in a diverse number of companies with a successful outcome. To achieve this the search for a number of companies where the first stages of the project and get implementation in the project will be necessary and make them understand the implementation as a process of improvement and to obtain a competitive advantage.

Modular development

The resulting application must be useful for any type of company so it must have a modular development, covering basic modules for basic operations: invoicing accounting, treasury, orders, sales, purchases, stock etc. to those not necessary for all companies such as production management, budget control, presence control, maintenance and those that arise on the part of the participants and from the needs of the users.

The development of these modules must be carried out gradually in such a way that that the initial modules supply a complete operating system for companies with few functionalities and more complex companies check the benefits of using the application under development and then complete its development with their specific needs.

This modular development must allow companies from different sectors, other than the traditional commercial or manufacturing sector, such as those in the service sector in the general sense (banks, insurance, health, services, etc.) to take advantage of the application developed.

INFORMATION TECHNOLOGIES

One of the features that the developed application must have is that it uses current information technologies and be prepared for the addition of those of the future at the moment still under development. Among these features, the independence of the operating system and the possibility of its use on a private network (intranet and extranet) or public (internet) must be included. Other important aspects are the application of standards such as Java and XML as well as the aforementioned UML.

Internet

Internet has established itself as the medium with which the applications of a company must be executed so they have access to them from anywhere and avoid local installation of software, for the task of maintenance involved in spite of the existing tools for management. For this an ERP application whose intention is that all workers in the company use it must be developed to work on the internet, whether as intranet or as extranet.

Architecture

The architecture of the informatic applications has evolved from mainframe systems with access terminals linked to the central system to the model known as client - server where the data is stored in a server and the applications are executed in the clients

medium the architecture has returned the main part of the work back to the servers although dividing it into different categories (data server, application server , Web server).

The features of ERP serve to confirm this tendency, so the development will focus on data models, business rules and the presentation of data to clients of different types (navigators, mobiles, pocket computers, other systems of data exchange).

Java

For the development of an internet application the accepted language is at the moment Java, which after some years when it was used fundamentally for client applications, it is becoming more widespread as a language for programming servers.

This choice is linked to the architecture selected, where information (data, rules, presentation) is made in the server and is presented to customers independently of its content.

Business rules are implemented with EJB’s (Enterprise Java Beans), the data presentation is done with Java servlets that allow the information management of each client through different connections and the information is stored in relational data bases.

Standard XML

Many of the tasks of an ERP system are based on editing the information on the data base tables, whether in a direct practical way (for example, editing customer data) or through processes (for example, introducing an order). The traditional applications carried out for each of these tasks a specific form which has a code for the subject involved, the tables and fields in the data base where the information is registered, the operation that can be carried out in the different registers (consult, navigate, edit, modify, delete, add, compute, …).

If we wish to design an application that is easily configured by each company and if we wish to develop it quickly the development of uses that allow the design of standardised forms will be necessary.

For this task the standard XML is apt (Extended Markup Language). In fact this is not a language but a method to define languages aimed at the publication of information and at information exchange. It concerns an adaptation of SGML which HTML is based on but allows any user (company, association, sector, etc.) to define the tags that are used in the definition of the information.

Standard XML has been adopted by leading companies in the information technology sector and definition documents are being developed for a wide variety of applications and sectors. This point in association with the tools that are being developed for the handling of information in XML on Java applications makes the decision to its use more than justified.

The way to use XML standard is defining the forms of the ERP application in this language. So a DTD (Document Type Definition) is defined with the syntax of the elements that can be used to define the forms. These elements will be the different from controls, the references to the data base and all those elements that allow the working of the forms.

The interaction of the clients will be carried out with an application server which reads the structure of the forms used and depending on them produces the client presentation. The client interacts with this presentation and as a result asks for it again and/or sends information to the server that registers the situation of the client session which means it is behaving like an application and not as a simple navigation.

The application server is an general application that shows the forms depending on the XLM files. This application server can be built in different ways, for example it can

serve HTML files or send XML information which asks for an applet or a general application from the client to show this information.

Features

Some of the features which the application will have are:

Administration of the forms managed by the server, with the knowledge of the users

that each one uses.

• The possibility of changing the forms at the time of execution, in such a way that two users can be working with different versions of the same form.

• On-line help, defined in the same XML file.

• Accounting options to make possible the logging of operations discriminated by type of operation, form or user.

• Access assured based on users and passwords for the data base or on security by user.

CONCLUSIONS

This concerns an ambitious project because of the size and reach of the developed application but is considered as feasible because of the reasons explained above. The aim of this task is to establish the base and to initiate the conditions for the development of the project. We hope that the next article explains the state of the development or the results obtained.

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GRAHAM HAMILTON, RICK CATTELL, and MAYDENE FISHER (1997): JDBC

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JOSÉ ANTONIO HERNÁNDEZ MUÑOZ (1998): Así es SAP R/3, Osborne Mc Graw-Hill. BENOIT MARCHAL (1999): XML by Example, QUE.