Can you elaborate on the four phases of the Systems Development Life Cycle (SDLC)? Where does the system requirements definition fit within the SDLC? Solution Systems Development Life Cycle: Planning Analysis Design Development Integration and testing Deploying Planning : Analysis : Design : Development : Integration and testing : Deployment : In SDLC phases planning, analysis, design, development and testing phases are very important.Few will do both development and testing in same phase. Client requirement will be taken in planning phase and software,hardware requirement will be taken in design phase..