Waterfall Model Advantages and Disadvantages

Anyone working in the field of software development will of course be aware of the famous waterfall model. It is nothing but the life cycle through which a project goes. Here, in this article, we will try to be aware of the waterfall model advantages and disadvantages…

The original waterfall model, published by Winston W. Royce in 1970, was in fact not identified by the very name with which we know it today. Royce, in fact, presented the model as a flawed and non-working model. But because of the various advantages that this approach towards software designing and implementation presented, it soon became very popular in the world of software development. However, before going into the waterfall model advantages and disadvantages, here is the waterfall model explained briefly. Read more on waterfall – software development model.

Waterfall Model – Software Development Model

The most important aspect of the waterfall model is that none of the stages can be started off with before the preceding stage is complete. The software life cycle has to follow the sequence. The original waterfall model designed by Royce consisted of the following seven stages:

• Specification of Requirements
• Design
• Construction
• Integration
• Testing and Debugging
• Installation
• Maintenance

However, various modifications were brought over to this waterfall model as and when required. Here, in this article, we will try to understand a simple waterfall model, broken into six stages. There is a seventh stage which is same as that of the first stage, requirements, but it follows the last stage and is referred to as updated maintenance. Let us try to understand each of these stages one by one.

Stage 1: Requirement Phase

Whether you design a small program to add two numbers or you are into developing a software system for the automation of an entire airline company, this is the first stage which can never be overridden. Unless you know what you are going to design, you cannot approach the problem. Here, the specifications of the output or the final product is studied and marked. If the software that is going to be designed should not contain certain features, for reasons like security, then it is also mentioned in this stage.

Stage 2: Specification Phase

With all the requirements and constraints in hand, a final view of how the product should exactly be, is decided. The exact way in which the software should function is mentioned in this stage.

Stage 3: Design Phase Well, here the actual work begins. Every type of resource which will be required for the smooth designing of the software is mentioned here in this phase. What type of database

will be required, what type of data should be supported, etc. are some of the important aspects that are decided in this phase. The algorithm of the process in which the software needs to be designed is made in this phase. This algorithm forms the backbone for the actual coding part in the next phase.

Stage 4: Implementation and Testing Phase Now starts the coding part. Here, the software is designed as per the algorithm. Hence it becomes very important that the algorithm should be properly designed. The software designed as per the algorithm needs to go through constant software testing

and error correction processes to find out if there are any flaw or errors. The output of this stage should be a well designed software which is at par with the algorithm designed.

Stage 5: Integration and Testing Phase

Here the various codes designed by different programmers are integrated together and is tested if the software works as per the specifications provided. The setup of the final software which needs to be installed at the clients system is also designed and tested so that the client does not face any problem during the installation of the software. The product is then handed over to the client.

Stage 6: Maintenance Phase The work of software development

does not end with the handing of the software to the client. The software designers may have to constantly provide support to the client to resolve any of the issues which may arise. There may be some flaws which get detected during the actual implementation of the project. During the maintenance phase, support and debugging is provided for all such problems.

Stage 7: New Requirements Phase

Changing times may require that the product requirements be changed. The client company may be expanding into other fields and it may want new features to be added over to the existing software. Hence, it is very important that the updated requirements be taken from the client. This requires the entire product life cycle to start all over again.

Now, I hope that the small explanation given above must have helped you in understanding the waterfall model. With this knowledge in hand, let us try to understand the advantages and disadvantages of waterfall model. Read more on waterfall model in software engineering.

Waterfall Model Advantages and Disadvantages

Let us now try to answer the basic question, what are the advantages and disadvantages of waterfall model?

Advantages of Waterfall Model

The waterfall model is the oldest and most widely used model in the field of software development. There are certain advantages of the waterfall model, which causes it to be the most widely used model as yet. Some of them can be listed as under.

• Needless to mention, it is a linear model and of course, linear models are the most simple to be implemented.
• The amount of resources required to implement this model is very minimal.
• One great advantage of the waterfall model is that documentation is produced at every stage of the waterfall model development. This makes the understanding of the product designing procedure simpler.
• After every major stage of software coding, testing is done to check the correct running of the code.

Disadvantages of Waterfall Model

The question that must be bothering you now is that with so many advantages at hand, what could be the possible disadvantages of the waterfall model. Well, there are some disadvantages of this widely accepted model too. Let us look at a few of them.

• Ironically, the biggest disadvantage of the waterfall model is one of its greatest advantage. You cannot go back, if the design phase has gone wrong, things can get very complicated in the implementation phase.
• Many a times, it happens that the client is not very clear of what he exactly wants from the software. Any changes that he mentions in between may cause a lot of confusion.
• Small changes or errors that arise in the completed software may cause a lot of problem.
• The greatest disadvantage of the waterfall model is that until the final stage of the development cycle is complete, a working model of the software does not lie in the hands of the client. Thus, he is hardly in a position to mention if what has been designed is exactly what he had asked for The waterfall model

, as already mentioned, is of course the most widely used model. There are various versions of the same, which allow some waterfall model phases to overlap or feedback to be taken after each phase, which make designing the software a lot more simpler. So this, in short, was all about waterfall model advantages and disadvantages. In spite of the disadvantages, the many advantages of this model ensure that it remains one of the most popular models used in the field of software development.