The document discusses different software development life cycle (SDLC) methodologies, including the waterfall model and agile model. The waterfall model is the oldest and simplest linear sequential model where each phase must be completed before the next begins. Its advantages are its simplicity and ease of management, while its disadvantages include difficulty making changes and high risks. The agile model is iterative with work done in short cycles (sprints) to iteratively develop working software. Its advantages include continuous improvement and adaptability, while potential disadvantages include lack of documentation and processes. For scaling up Facebook in 2006, an agile model would be chosen to allow for rapid iterations and incorporation of user feedback as the platform grows. Depart

1. SOFTWARE
DEVELOPMENT LIFE
CYCLE

2. Q. What is Software development life cycle?
It is a conceptual model used in Product Management that describes the stages involved in an
information system development project.
 There are 6 basic SDLC methodologies:
i. Waterfall Model: Oldest one & most straight-forward,
ii. V-shaped Model,
iii. Iterative Model,
iv. Spiral Model,
v. Big Bang Model and
vi. Agile Model.

3. Waterfall Model
 The waterfall model is a classical model used in system development life cycle to create a system with a linear and sequential
approach. It is termed as waterfall because the model develops systematically from one phase to another in a downward
fashion.
This is the oldest and simplest model. In waterfall, development of one
phase starts only when the previous phase is complete.
 Advantages:
i. Simple and easy to understand and use.
ii. Easy to manage due to the rigidity of the model.
iii. Phases are processed and completed one at a time and phases are clearly defined.
iv. Works well for smaller projects where requirements are very well understood.
 Disadvantages:
i. Makes changes difficult. No working software is produced until late during the life cycle.
ii. High amounts of risk and uncertainty.
iii. This is not a good model for complex and object-oriented projects. And it’s a very poor model for long and ongoing projects.

4. Agile Model
 Agile SDLC methodology is based on collaborative decision making between requirements and solutions teams, and a cyclical,
iterative progression of producing working software. Work is done in regularly iterated cycles, known as sprints, that usually last
two to four weeks.
This is the most useful model now a days. This Method breaks the product into small incremental builds. These builds are provided in
iterations.
 Advantages:
i. Continuous improvement & Superior quality product.
ii. Reduced risks and Improved project predictability.
iii. An Agile approach is best-suited for a relatively uncertain environment.
 Disadvantages:
i. Teams get easily side-tracked due to lack of processes.
ii. More time and commitment & Less predictability.
iii. Lack of necessary documentation.
Agile Frameworks: Scrum, Kanban, Lean, XP, Crystal.

5. Q. Let's suppose it is 2006, you are Mark Zuckerberg and you have an initial
traction on Facebook.com and its time to scale the platform up. Which SDLC
model will you choose and why?
Explain with a 1-year strategy on how are you going to scale the platform for
the next year?
What will be the various departments involved in your company and how will
you manage these departments? Explain the management on all the
departments you can think of, in detail.

6. THANKYOU!