2. Topic:-

3. At the end we will be able to explain:- Why it is called Meta Model ?? Spiral Model Its Advantages & Disadvantages… Phases of Spiral Model... When we use it ??

4.  The spiral model, also known as the spiral lifecycle model, is a systems development lifecycle (SDLC) model used in information technology (IT). This model of development combines the features of the prototyping model and the waterfall model.SDLCwaterfall model  IT WAS FIRST PROPOSED BY barry BOEHM in 1986.  In Spiral model we can arrange all the activities in the form of a spiral.

5.  This model is best used for large projects which involves continuous enhancements.  In Spiral model we can arrange all the activities in the form of a spiral.  This model is best used for large projects which involves continuous enhancements.  In Spiral model we can arrange all the activities in the form of a spiral.

6. Spiral model is also called as meta-model because in a way it comprises of other models of SDLC. Both waterfall and prototype models are used in it. We are able to reduce risks as well as follow systematic approach.

7. Prototype The prototyping model is a systems development method (SDM) in which a prototype is built, tested, and then reworked as necessary until an acceptable prototype is finally achieved. 7

8. Phase in spiral model PLANRisk Analysis Engineering Customer evaluation

9. To explain in simpler terms, the steps involved in spiral model are:

10. Planning phase Risk analysis phase Engineering phase Evaluation phase

11.  Requirements are studied and gathered  Reviews and walkthroughs to streamline the requirements  Requirements understanding document  Finalized list of requirements  Requirements are studied and gathered  Reviews and walkthroughs to streamline the requirements  Requirements understanding document  Finalized list of requirements

12.  All possible alternatives, which can help in developing a cost effective project are analyzed.  This phase identify and resolve all the possible risks in the project development.  All possible alternatives, which can help in developing a cost effective project are analyzed.  This phase identify and resolve all the possible risks in the project development.

13.  Actual development and testing if the software takes place in this phase  Code  Test cases and test results  Test summary report and defect report  Actual development and testing if the software takes place in this phase  Code  Test cases and test results  Test summary report and defect report

14.  Customers evaluate the software and provide their feedback and approval  Features implemented document  Includes evaluation of software by the customer and implementing feedback in the next iteration of the software development  Customers evaluate the software and provide their feedback and approval  Features implemented document  Includes evaluation of software by the customer and implementing feedback in the next iteration of the software development

15.  Development is fast.  Larger projects / software are created and handled in a good planning way.  More and more features are added in a systematic way.  Software is produced early.  Customer can full fill their requirement as their own will.  Development is fast.  Larger projects / software are created and handled in a good planning way.  More and more features are added in a systematic way.  Software is produced early.  Customer can full fill their requirement as their own will.

16.  Risk analysis is important phase so requires expert people.  Is not beneficial for smaller projects.  Spiral may go infinitely.  It is costly for smaller projects.  Risk analysis is important phase so requires expert people.  Is not beneficial for smaller projects.  Spiral may go infinitely.  It is costly for smaller projects.

17.  When the project is large.  For medium to high-risk projects.  Users are unsure of their needs.  Significant changes are expected.  Requirements are complex.  When the project is large.  For medium to high-risk projects.  Users are unsure of their needs.  Significant changes are expected.  Requirements are complex.