Software Development Life Cycle

Software Development Life Cycle:

The software development life cycle begins with the identification of requirement for software and ends with the formal verification of the development software against that requirement.

In V-Shaped model the development and testing phase are carried out parallel sequence i.e. Verification on one side and validation on other side.

Advantage: As the verification and validation are done along with the test management. The outcome of V shaped model is a quality product.

Drawback: Time consuming and costly model.

Water fall model: in this model the development and testing phase are carried out step by step process and a base line document is prepared.

Advantage: It’s simple model and easy to maintain, project implementation is very easy.

Drawback: Can’t incorporate new changes in the middle of the project development. Base line document.

Prototype Model (Rapid Prototype model):-

This is cyclic version of the linear model. In this model once the requirement analysis is done and the design for a prototype is made, the development process gets started. Once the prototype is created. It is given to the customer for evaluation. The customer tests the package and gives his/her feedback to the developer who refines the product according to the customer’s exact expectation. After a finite number of iterations, the final software package is given to the customer. In this methodology the software is evolves as a result of periodic shuttling of information between the customer and developer.

Photo typing is the process of quickly putting together a working model (a prototype) in order to test various aspects of a design illustrate ideas or feature and gather largely user feedback.

Advantage: When even the customer with the requirement that this is the best model together the clear requirement.

Drawbacks:

·         It is not a complete model.

·         Time consuming model

·         Prototype has to be build company cost.

·    The user may strict to the prototype and limit his requirements

Spiral Model: The spiral model is similar to the incremental model with more emphasis placed on risk analysis. The spiral model has four phases: Planning, Risk Analysis, Engineering and Evaluation. A software project repeatedly passed through these phases in iterations (called spirals in this model). The baseline spirals, starting in the planning phase requirement are gathered and risk is assessed. Each subsequent spiral builds on the baseline spiral.

Advantage:  

·         High amount of risk analysis.

·         Good for large and mission critical projects.

·         Software is produced early in the software life cycle

Disadvantage:

·         Can be costly model to use.

·         Risk analysis requires highly specific expertise.

·         Project’s success is highly dependent on the risk analysis phase.

·         Doesn’t work well for smaller projects.