Post 2_Types of SDLC lifecycle

First I would want to cover What a BA should know. To start with lets do the type of SDLC methodologies

We would primarily focus on the below ones.

- Waterfall model

- Iterative Model

- Latest one - Agile Methodology.

Brief about each of them

Waterfall model: Also known as Sequential software development approach. It follows the sequence of steps for full requirements together. So how does it work ?

- BA finishes the Requirement Gathering phase.

- Then comes Desgin stage

- Development stage

- Integration

- Testing

- Production

- Maintanence

Once each stage is passed. Its closed. Waterfall model is good for the project where :

- Client is thorough with the requirements,

- Team is working with well understood technical tools, architecture and infrastructure.

Iterative Model: It doesnt start with full set of requirements from the beginning. Each set of requirement goes throguh design, development , testing integration and production. We develop specific part of the software, which is then reviewed in order to identify next set of requirements. produce a new version of software for each cycle in the model.

Success if Iterative model is rigorous validation of requirements and testing of each  version of the software.

Agile Model: Its an approach for effective modeling and documentation of software system. Its applied on Requirements, analysis, architecture and design.

Agile focus on shorter iterations. This helps in maintaining quality, reduced integration risk, frequent evidence of progress, good status visibility and customer relations.

The pre-determined iteration length serves as a timebox for the team.  Scope is chosen for each iteration to fill the iteration length.  Rather than increase the iteration length to fit the chosen scope, the scope is reduced to  fit the iteration length.  A key difference between agile methods and past iterative methods is the length of each iteration.  In the past, iterations might have been three or six months long.  With agile methods, iteration lengths vary between one to four weeks,  and intentionally do not exceed 30 days. 

There are further 4 types of Agile development methodolgies

- Extreme programming (XP)

- Crystal

- Scrum

- Feature driven development

Please feel free to add if you have experience in any of the agile methods.