What is Spiral Model
What is Spiral Model
Spiral Model is one of the mostly useges process model for development of large scale application or inhanced application. Spiral Model is a risk-driven software development process model. It is a combination of waterfall model and iterative model.
Spiral Model helps to adopt software development elements of multiple process models for the software project based on unique risk patterns ensuring efficient development process. Each phase of spiral model in software engineering begins with a design goal and ends with the client reviewing the progress. The spiral model in software engineering was first mentioned by Barry Boehm in his 1986 paper.
In spiral model application development will be done in different cycle at last all the cycle should be integrated, every cycle contains these phases.
- Requirment gathering
- Analysis and design
- Coding and Testing
- Plan for next itteration
Advantages of Spiral Model
Below are some advantages of the Spiral Model.
Risk Handling: The projects with many unknown risks that occur as the development proceeds, in that case, Spiral Model is the best development model to follow due to the risk analysis and risk handling at every phase.
Good for large projects: It is recommended to use the Spiral Model in large and complex projects.
Flexibility in Requirements: Change requests in the Requirements at later phase can be incorporated accurately by using this model.
Customer Satisfaction: Customer can see the development of the product at the early phase of the software development and thus, they habituated with the system by using it before completion of the total product.
Disadvantages of Spiral Model
Below are some main disadvantages of the spiral model.
Complex: The Spiral Model is much more complex than other SDLC models.
Expensive: Spiral Model is not suitable for small projects as it is expensive.
Too much dependability on Risk Analysis: The successful completion of the project is very much dependent on Risk Analysis. Without very highly experienced experts, it is going to be a failure to develop a project using this model.
Difficulty in time management: As the number of phases is unknown at the start of the project, so time estimation is very difficult.
When to use Spiral Model?
- When the project is large
- Large and high budget projects
- When releases are required to be frequent, spiral methodology is used
- When creation of a prototype is applicable
- When risk and costs evaluation is important
- Spiral methodology is useful for medium to high-risk projects
- When requirements are unclear and complex, Spiral model in SDLC is useful
- When changes may require at any time
- When long term project commitment is not feasible due to changes in economic priorities
Advantages of Spiral Model
- Additional functionality or changes can be done at a later stage
- Cost estimation becomes easy as the prototype building is done in small fragments
- Continuous or repeated development helps in risk management
- Development is fast and features are added in a systematic way in Spiral development
- There is always a space for customer feedback
Disadvantages Spiral Model
- Risk of not meeting the schedule or budget
- Spiral development works best for large projects only also demands risk assessment expertise
- For its smooth operation spiral model protocol needs to be followed strictly
- Documentation is more as it has intermediate phases
- Spiral software development is not advisable for smaller project, it might cost them a lot