Define Agile Model and its Advantages

Define Agile Model and its Advantages

Agile Model or Agile Methodology :

Agile development methodology attempts to provide many opportunities to assess the direction of a project throughout the development life cycle. Agile methods break tasks into small increments with minimal planning and do not directly involve long-term planning. Iterations are short time frames that typically last from one to four weeks. Each iteration involves a cross functional team working in all functions: planning, requirements analysis, design, coding, unit testing, and acceptance testing. At the end of the iteration a working product is demonstrated to stakeholders. This minimizes overall risk and allows the project to adapt to changes quickly. An iteration might not add enough functionality to warrant a market release, but the goal is to have an available release at the end of each iteration. Multiple iterations might be required to release a product or new features.

Advantages and Dis-advantages of V-model

Advantages of V-model (SDLC)

These are the advantages V-Model offers in front of other systems development models:

• The users of the V-Model participate in the development and maintenance of The V-Model. A change control board publicly maintains the V-Model. The change control board meets anywhere from every day to weekly and processes all change requests received during system development and test.
• The V-Model provides concrete assistance on how to implement an activity and its work steps, defining explicitly the events needed to complete a work step: each activity schema contains instructions, recommendations and detailed explanations of the activity.

Advantages and Dis-advantages of Waterfall Model

What are the Advantages & Dis-advantages of Waterfall Model

Advantages of waterfall model:

• It allows for departmentalization and managerial control.
• Simple and easy to understand and use.
• Easy to manage due to the rigidity of the model – each phase has specific deliverables and a review process.
• Phases are processed and completed one at a time.
• Works well for smaller projects where requirements are very well understood.
• A schedule can be set with deadlines for each stage of development and a product can proceed through the development process like a car in a car-wash, and theoretically, be delivered on time.

What is Waterfall model and list its advantages, disadvantages

What is Waterfall model

List its advantages and disadvantages

What is Waterfall Model ?

The waterfall model is a popular version of the systems development life cycle model for software engineering. Often considered the classic approach to the systems development life cycle, the waterfall model describes a development method that is linear and sequential. Waterfall development has distinct goals for each phase of development. Imagine a waterfall on the cliff of a steep mountain. Once the water has flowed over the edge of the cliff and has begun its journey down the side of the mountain, it cannot turn back. It is the same with waterfall development. Once a phase of development is completed, the development proceeds to the next phase and there is no turning back.

V-Model in SDLC (Software Development Lifecycle)

V-Model in SDLC (Software Development Lifecycle)

The V-model represents a software development process (also applicable to hardware development) which may be considered an extension of the waterfall model. Instead of moving down in a linear way, the process steps are bent upwards after the coding phase, to form the typical V shape. The V-Model demonstrates the relationships between each phase of the development life cycle and its associated phase of testing. The horizontal and vertical axes represents time or project completeness (left-to-right) and level of abstraction (coarsest-grain abstraction uppermost), respectively.

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Overview : 

The V-model is a graphical representation of the systems development lifecycle. It summarizes the main steps to be taken in conjunction with the corresponding deliverables within computerized system validation framework.

The V represents the sequence of steps in a project life cycle development. It describes the activities to be performed and the results that have to be produced during product development. The left side of the "V" represents the decomposition of requirements, and creation of system specifications. The right side of the V represents integration of parts and their validation.

It is sometimes said that validation can be expressed by the query "Are you building the right thing?" and verification by "Are you building it right?"

In practice, the usage of these terms varies. Sometimes they are even used interchangeably.

The PMBOK guide, an IEEE standard, defines them as follows in its 4th edition:

"Validation. The assurance that a product, service, or system meets the needs of the customer and other identified stakeholders. It often involves acceptance and suitability with external customers. Contrast with verification."

"Verification. The evaluation of whether or not a product, service, or system complies with a regulation, requirement, specification, or imposed condition. It is often an internal process. Contrast with validation."

Software Development Lifecycle (SDLC) Models

Software Development Lifecycle (SDLC) Models

What is Software Development Lifecycle (SDLC) :

The software development life cycle (SDLC) is a conceptual model used in project management that describes the stages involved in an information system development project, from an initial feasibility study through maintenance of the completed application/product.

1. Understand the relationship between development, test activities and work products in the Development life cycle and give examples based on project and product characteristics and context.
2. Recognize the fact that software development models must be adapted to the context of project and product characteristics.
3. Recall reasons for different levels of testing and characteristics of good testing in any life cycle model.