Software Development Life Cycle by A.Surasit Samaisut Copyrights : All Rights Reserved

Page  2 Introduction to SDLC – Definitions  System Development Life Cycle (SDLC)  Also know as; Software Development Life Cycle  Is a systematic approach to solving business problems  Is the process of creating or altering systems, and the models and methodologies that people use to develop these systems  Is any logical process used by a systems analyst to develop an information system, including requirements, validation, training, and user ownership

Page  3 The Concepts of SDLC  The concept generally refers to computer or information systems  Basic process of system development from start to finishing the system  It is divided into seven phases, each phase has unique activities Systems Analysis and Design by Kendall and Kendall

Page  4 SDLC: Phase 1 – Identifying  Identifying Information To generate a high-level view of the intended project and determine the goals of the project. Problems: basic problems and technical problems Opportunities: business plan Competitors : market share / initiator Objectives and Goals

Page  5 SDLC: Phase 2 – Determining  Determining Information Requirements Interview management, operations personnel Gather systems/operating documents Use questionnaires Observe the system and personnel involved  who, what, where, when, why, how

Page  6 SDLC: Phase 3 – Analyzing  Analyzing system needs Create data flow diagrams Document procedural logic for data flow diagram processes Complete the data dictionary Make semi structured decisions Prepare and present the system proposal Recommend the optimal solution to management

Page  7 SDLC: Phase 4 – Designing  Designing the recommended system In systems design functions and operations are described in detail, including screen layouts, business rules, process diagrams and other documentation. The output of this stage will describe the new system as a collection of modules or subsystems Basics –Design the user interface and produce program specifications Techniques –Design system controls, files and/or database and produce decision trees or tables

Page  8 SDLC: Phase 5 – Developing  Developing and documenting software Design computer programs using structure charts, and pseudocode Walkthrough program design Write computer programs / coding Document software with help files, procedure manuals, and Web sites with Frequently Asked Questions

Page  9 SDLC: Phase 6 – Testing  Testing and Maintaining the system Test and debug computer programs Test the computer system Enhance system

Page  10 SDLC: Phase 6 – Types of Testing  Types of testing: Data set testing Unit testing System testing Integration testing Black box testing White box testing Module testing Regression testing Automation testing User acceptance testing

Page  11 SDLC: Phase 7 – Evaluating  Implementing and Evaluating the system Plan conversion Train users Purchase and install new equipment Convert files Install system Review and evaluate system

Page  12 SDLC – The 7 Phases Identifying Determining Analyzing Designing Developing Testing Evaluating

Page  13 Strengths of SDLC  Control  Monitor large projects  Detailed steps  Evaluate costs and completion targets  Documentation  Well defined user input  Ease of maintenance  Development and design standards  Tolerates changes in MIS staffing

Page  14 Weaknesses of SDLC  Increased development time  Increased development cost  Systems must be defined up front  Rigidity / inflexibility  Hard to estimate costs, project overruns  User input is sometimes limited

Page  15 Alternatives to SDLC  Rapid Application Development Refers to a type of software development life cycle which uses minimal planning in favor of rapid prototyping The lack of extensive pre-planning generally allowed software to be written much faster, and makes it more flexible to change in requirement  Waterfall Model is a sequential software development process, in which progress is seen as flowing steadily downwards (like a waterfall) through the 5 phases

Page  16 SDLC – Checkpoint  Translating the algorithm into a programming language occurs at the which step of the SDLC? Developing Phase  The make-or-buy decision is associated with the which step in the SDLC? Designing Phase  Testing process is initially perform in which step of SDLC? Developing Phase