Software Development Life Cycle (SDLC)

• Software Development Life Cycle (SDLC) is a term used by the software industry to define a process for designing, developing, testing and maintaining a high quality software product.
• Also known as Software Development Process.
• The goal is to use SDLC defined processes to develop a high quality software product that meets (in fact, exceeds) customer demands.
• ISO/IEC 12207 is an international standard for software life-cycle processes.

Phases of SDLC

Phase#1: Planning and requirements definition

• Planning includes clearly identifying customer and/or market needs, pursuing a feasibility study and arriving at an initial set of requirements.
• Requirements definition includes documenting detailed requirements of various kinds: System-level, functional, software, hardware, quality requirements etc. They get approved by appropriate stakeholders.
• Requirements analysis includes checking and analyzing requirements to ensure that they are consistent, complete and match the feasibility study and market needs.

Typical work products: Requirements documents of various kinds, project plan.

Phase#2: Design and Architecture

• Design identifies all the modules of the software product, details out the internals of each module, the implementation details and a skeleton of the testing details.
• Architecture defines the modules, their connections and other dependencies, the hardware, database and its access etc.
• Design and architecture are hand in glove with each other.
• Usually, validation of the design and architecture is done.

Typical work products: Design and architecture documents or models.

Phase#3: Development