What is a Spiral Model?
Definition : The spiral model in software engineering is one type of model of the software development lifecycle. SDLC is a step-by-step procedure to develop software or applications. It is also similar to the incremental model. In this spiral model sdlc, there are four main stages: Planning, Risk Analysis, Engineering,
and Evaluation.
Spiral Model Phases
There are four spiral model phases:
Planning:
In this phase, first of all, requirements gathered from customers during this planning stage. Requirements such as CRS (Customer Requirement Specification), SRS(Software Requirement Specification), and BRS(Business Requirement Specification).
Risk Analysis:
Due to main focus on this phase is identifying the risk and its solutions. So if any kind of risk found during this phase, then solutions implemented.
Engineering:
During this phase, the software developed with testing. So both development and testing is completed during this phase.
Evaluation:
The main purpose of this phase is to allow the client to evaluate the output before starting the next spiral.
Spiral Model Diagram
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Spiral Model Advantages And Disadvantages
Advantages and Disadvantages of Spiral Model are shown below:
Advantages Of Spiral Model
- It is good for big and complex projects
- It can be added at the mid-level of projects.
- It has strong controls on documentation.
- In this phase, it has more chances to produce software in the early software life cycle.
Disadvantages Of Spiral Model
- This model can be costly to use.
- It should require high expertise in risk analysis.
- The dependency on risk analysis is high due to the project’s success.
- It is not suitable for small projects.
Uses
- This model is useful when costs and risk evaluation required.
- When there is a medium to the high-risk project at that time we can use this model.
- When customers are not clear about their requirements.
- When rapidly changes expected
- Requirements are complex.
Conclusion
So as above, spiral model of software development is mainly focused on risk-based projects. Also, this model is used when the requirements are complex. If you are looking for more sdlc models then please visit below link.
4. RAD Model