Revision as of 17:37, 21 September 2017

Most software development projects apply either the Waterfall or Agile methodology. A development methodology is the procidure used by an engineering team in order to create a desired product. The Waterfall methodology represents the traditional approach, where the development process is conducted in a linear series of events. On its way toward the conclusion the progress flows continously through the phases of a project (analysis, design, development, testing) like a waterfall. The entire project is planned in advance. Agile is a more recently developed software development methodology, where the linear approach is replaced by an incremental, iterative one. Instead of planning the whole project in advance, Agile enables the adaption of requirements during the whole project. This artice provides an introduction of each methodology, a comparison and examples of use, in order to facilitate the decision whether Agile or Waterfall is more suitable for the next project.

Waterfall Methodology

The lifcycle model which is today known as traditional or Waterfall model was first described by Royce in 1970.^[1] It is called Waterfall model because of its sequential and down-flow characteristic where the phases analysis, design, implementation and testing are processed consecutively downwards.^[2] Each phase of the Waterfall model is processed in order without any overlapping and within a specified time period. Once a phase is completed there is no going back to a privious phase as it will be frozen.^[3]

Analysis In this phase all the requirements of the desired system or product are gatherd and recorded in detail in a specification document.^[4] The requirements of the product should be clear before moving to the next phase as changes in requirement can not be adapted later in the process.^[5]

Design

Implementation

Testing

Pros

Cons

Agile Methodology

Pros

Cons

Comparison of the Waterfall and the Agile Methodology

Example of Use

The following example demonstrates the different approaches of each methodology. The project goal is the development of a customer adress book.

Waterfall Model

Product Requirements

First, the Product Manager has to create a document of requirements:

• Enable user to create new contacts

• Enable user to see his contacts

• Enable user to import contacts from other applications

• Enable user to email his contacts from the adress book

• Enable user to add pictures to represent his contacts

The created document will comprise detailed requirements, user scenarios and potential layouts

Analysis

Design

Implementation

Testing

Release

Agile Model

Product Requirements

The product manager creates a document of requirements:

• Enable user to create new contacts

• Enable user to see his contacts

• Enable user to import contacts from other applications

• Enable user to email his contacts from the adress book

• Enable user to add pictures to represent his contacts

Iteration Nr.1

Iteration Nr.2

Iteration Nr.3

Release

Conclusion

References

1. ↑ Sommerville I., "Software process models," ACM Computing Surveys (CSUR), vol. 28, pp. 269-271, 1996
2. ↑ Dubey A.; Jain A.; Mantri A., "COMPARATIVE STUDY: WATERFALL V/S AGILE MODEL", INTERNATIONAL JOURNAL OF ENGINEERING SCIENCES & RESEARCH TECHNOLOGY (IJESRT), 2015
3. ↑ Balaji S.; Dr. Sundararajan Murugaiyan M., "WATEERFALLVs V-MODEL Vs AGILE: A COMPARATIVE STUDY ON SDLC", International Journal of Information Technology and Business Management (JITBM), 2012
4. ↑ Dubey A.; Jain A.; Mantri A., "COMPARATIVE STUDY: WATERFALL V/S AGILE MODEL", INTERNATIONAL JOURNAL OF ENGINEERING SCIENCES & RESEARCH TECHNOLOGY (IJESRT), 2015
5. ↑ Balaji S.; Dr. Sundararajan Murugaiyan M., "WATEERFALLVs V-MODEL Vs AGILE: A COMPARATIVE STUDY ON SDLC", International Journal of Information Technology and Business Management (JITBM), 2012