Spiral Methodology
Computer Science: OCR A Level, topic 2.3.8
Spiral Methodology
When working in software development organisations follow software development systems to ensure the project is a success. The spiral methodology is one such system.
Spiral methodology
- The spiral methodology is similar to the waterfall lifecycle but features an iterative agile aspect to it.
Stage 1: Identification
- The client and the project team collaborate to establish requirements from the user.
- After the first spiral, this stage is also used to review what has been achieved before and what needs to be added.
Stage 2: Design
- The project team then enter into the design stage.
- During the first spiral they will develop a conceptual design for the project.
- Then architectural design in the next spiral, then logical design and finally a physical design in the subsequent spirals.
Stage 3: Construction
- The team will then enter the construct stage to develop the agreed requirements.
- During the first spiral a proof of concept version will be built to get feedback from the client, then functionality will be added in each spiral.
Stage 4: Evaluation and risk assessment
- Then finally evaluation and risk assessment is used to evaluate the product by the client and assess the risk of what still needs to be done.
- This information is then fed back into the next spiral.
Merits & Drawbacks of the Spiral Methodology
Software development methodologies are suitable in different situations and all of them have positive and negatives.
Merits of spiral methodology
- With the spiral methodology, a product can be developed at each cycle and more added to the system after each spiral.
- This means the user sees a system very early on.
- Spiral makes use of prototypes.
- The client is able to see the product being developed to ensure it is what they want.
Drawbacks of spiral methodology
- Like other agile methodologies, spiral can easily fall off track and the costs and time scales can escalate quickly.
- The client is needed to make a significant time investment for feedback and evaluation to steer the project.
- Spiral, again like other agile methodologies, produces poor quality documentation compared to waterfall.
Usage
- Spiral is best suited to projects where the client can heavily invest their time in guiding what is being produced.
- The client should have a clear idea of what they want.
Test yourself on Spiral Methodology
Spiral Methodology
What happens during each spiral of the identification stage?
What happens after the first spiral is complete?