Latest Spiral Model Interview Questions
1. What is Spiral Model?
In the Spiral Model, a cyclical and prototyping view of software development is shown. Test are explicitly mentioned (risk analysis, validation of requirements and of the development) and the test phase is divided into stages.
The test activities include module, integration and acceptance tests. However, in this model the testing also follows the coding. The exception to this is that the test plan should be constructed after the design of the system. The spiral model also identifies no activities associated with the removal of defects.
2. Explain Top-down and bottom-up design?
Top-down and bottom-up are strategies of information processing and knowledge ordering, mostly involving software, but also other humanistic and scientific theories (see systemics). In practice, they can be seen as a style of thinking and teaching. In many cases top-down is used as a synonym of analysis or decomposition, and bottom-up of synthesis.
3. Explain Waterfall model?
The waterfall model is a sequential software development process, in which progress is seen as flowing steadily downwards (like a waterfall) through the phases of Conception, Initiation, Analysis, Design (validation), Construction, Testing and Maintenance.
4. What is V Model?
Many of the process models currently used can be more generally connected by the ‘V’ model where the ‘V’ describes the graphical arrangement of the individual phases. The ‘V’ is also a synonym for Verification and Validation.
By the ordering of activities in time sequence and with abstraction levels the connection between development and test activities becomes clear. Oppositely laying activities complement one another (i.e.) server as a base for test activities. For example, the system test is carried out on the basis of the results specification phase.
5. What is W Model?
From the testing point of view, all of the models are deficient in various ways:
The Test activities first start after the implementation. The connection between the various test stages and the basis for the test is not clear.
The tight link between test, debug and change tasks during the test phase is not clear.
6. Explain Butterfly Model of Test Development?
Butterflies are composed of three pieces – two wings and a body. Each part represents a piece of software testing, as under.
? Test Analysis
? Test Design
? Test Execution
7. What are the Strengths of Spiral model?
Spiral model provides early indication of insurmountable risks, without much cost.
Users see the system early because of rapid prototyping tools.
Critical high-risk functions are developed first.
The design does not have to be perfect.
Users can be closely tied to all lifecycle steps.
Early and frequent feedback from users.
Cumulative costs assessed frequently.
8. What are the weaknesses of Spiral model?
Time spent for evaluating risks too large for small or low-risk projects.
Time spent planning, resetting objectives, doing risk analysis and prototyping may be excessive.
The model is complex.
Risk assessment expertise is required.
Spiral may continue indefinitely.
Developers must be reassigned during non-development phase activities.
May be hard to define objective, verifiable milestones that indicate readiness to proceed through the next iteration.
9. When to use Spiral model?
When creation of a prototype is appropriate.
When costs and risk evaluation is important.
For medium to high-risk projects.
Long-term project commitment unwise because of potential changes to economic priorities.
Users are unsure of their needs.
Requirements are complex.
New product line .
Significant changes are expected (research and exploration).
10. What major shortcoming of the Waterfall Model does the Spiral Model address?
The Waterfall model provides no means for risk assessment and management during the life cycle.
11. How does the Spiral Model address the need of accurately determining the software requirements?
The Spiral Model addresses the problem of requirements engineering through the development of prototypes.
12. How does the Spiral Model handle the need for risk management?
The Spiral Model addresses the need for risk management by performing risk analysis and risk resolution during each spiral of the life cycle.
13. What are the eight management elements of the Spiral Model?
Objectives, constraints, alternatives, risks, risk resolution, results, plans, and commitment.
14. How many spirals does the Spiral Model contain?
The exact number of spirals necessary for a given project is flexible and depends on the number of prototypes needed to reach a satisfactory design.
15. How does the Spiral Model represent maintenance?
Maintenance simply becomes another spiral or phase in the life cycle of the software. Like the previous phase, the maintenance efforts undergo risk assessment to evaluate whether changes are feasible.
16. Explain how both the waterfall model and the prototyping model can be accommodated in the Spiral process model.
The waterfall model is accommodated where there is a low specification risk and no need for prototyping etc. for risk resolution. The activities in the 2nd quadrant of the spiral model are skipped. The prototyping model is accommodated when the specification phase is limited and the prototyping (risk resolution) phase predominates.
The activities in the 3rd quadrant of the spiral model are skipped or reduced in scope.
17. Which software process model best supports development of applications with successful user interfaces, and why?
Several do. The Spiral Model and any incremental model do. They work because the process allows users to state their initial goals and requirements, all the developers to work ahead a bit (do an initial UI design, e.g.), and then give the users the opportunity to review and rethink what they want.
18. Describe three ways in which the Spiral process model is superior to the Waterfall model.
Explicit provision for risk analysis and mitigation; explicit provision for replanning of the process, in mid-stream; explicit consideration at all stages of alternative approaches; supports exploratory prototyping. Other answers are also possible.