Software testing services offer a number of testing models. But for you to choose the right testing model, you need to be aware of the capabilities and shortcomings of each model. In this blog, we help you to choose the testing model that best suits your software testing needs.
Various approaches are used by software testers in software development processes. A software development process is also called a Software Development Life Cycle (SDLC). Here we will discuss about 5 of the most frequently used testing models and the advantages and disadvantages of using them in a Software Development Life Cycle.
1. Waterfall Model
Developed by Winston Royce in the early 1970's, it is one of the most basic life cycle models. It was the first successful process model with a sequential development phase. The process flows progressively like that of a waterfall through multiple phases and hence the name waterfall model. The model as such is divided in into the following phases:
- Requirement Gathering and Analysis phase
- Software Design
- Implementation and Testing
All the phases are sequential and each step is dependent on the previous one. This means that for a particular phase to begin, all the defined set of objectives and goals belonging to the previous step needs to be completed. This can sometimes become a disadvantage, but the simplicity in implementation and ease of maintenance is what fuels the popularity of this model.
The amount of resources required is minimal when compared to other models. A document is created after every phase of the model which helps to better understand and design the system. Creating deadlines for each stage helps to develop the system within a predetermined time frame. This model is rigid and lacks flexibility. It is impossible to make changes in the development of system.
To overcome the disadvantages of the Waterfall Model, an alternative called V Model was introduced. It enables testing at each phase of SDLC, while the Waterfall Model supports testing only in the end phase. This helped testers to find issues at the earlier stages rather than at the end.
Before the start of actual testing, the testing team works on various activities like preparing the Test Strategy, Test Planning, Creation of Test cases and Test Scripts. These work in parallel with the development activity, helping to get the test completed on time. It is also called the verification or validation model.
In this process the “Do-Procedure” is handled by the developer team whereas the “Check-Procedure” is followed by the testing team to meet the requirements. The V-model typically consists of the following phases:
1. Unit Testing: Preparation of Unit Test Cases
2. Integration Testing: Preparation of Integration Test Cases
3. System Testing: Preparation of System test cases
4. Acceptance Testing: Preparation of Acceptance Test Cases
3. Agile Model
Agile development model is a type of incremental model where the software is developed in incremental, rapid cycles. This produces small incremental releases with each release building on previous functionality. These releases are thoroughly tested to ensure software equality and the model is commonly used for time critical applications.
It helps in rapid and continuous delivery of useful software which ensures customer satisfaction. This model promotes constant interaction between customers, developers and testers, and even facilitates face-to-face conversation.
Such a model demands a clear cut idea about the output or else the project can easily be taken off track. It is difficult for a newbie programmer and constantly requires the services of an experienced hand.
Agile welcomes changes that need to be implemented. This can be done at an affordable cost because of frequent increments that are produced. Unlike the waterfall model, agile model requires very limited planning to get started with the project.
4. Spiral Model
It is similar to the incremental model but gives more emphasis on risk analysis. The spiral model has four phases:
- Risk Analysis
A software project repeatedly goes through these phases in iterations and in the baseline spiral, starting in the planning phase, requirements are gathered and risk is analysed. Each subsequent spiral builds on the baseline spiral.
There is a high amount of risk analysis taking place which helps to better avoid them. Additional functionalities can be added at a later stage of development. In spite of the advantages this is a costly model to use and also the process of risk analysis requires highly specific expertise.
This model is widely used when costs and risk evaluation is of prime importance, especially in those medium to high-risk projects. For users who are unsure of what they need, this model can be quite helpful.
It is an object-oriented and web-enabled program development methodology and is like an online mentor that provides guidelines, templates, and examples for all aspects and stages of program development. RUP is comprehensive software engineering tools that combine the procedural aspects of development with other components of development within a unifying framework.
RUP establishes four phases of development:
· Inception phase: Developers define the scope of the project and its business.
· Elaboration phase: Developers analyze the project's needs in greater detail and define its architectural foundation.
· Construction phase: Developers create the application design and source code.
· Transition phase: Developers deliver the system to users.