Case Technology - from Software Development Life Cycle (SDLC) to Software Engineering Life Cycle (SELC)

THE SOFTWARE DEVELOPMENT LIFE CYCLE (SDLC) MODEL IS A FUNDAMENTAL AND IMPORTANT CONCEPT IN THE HELD OF SOFTWARE ENGINEERING. AUTOMATION OF THE SOFTWARE PROCESS USING C A S E TECHNOLOGY IS BASED ON THE SOFTWARE DEVELOPMENT UFE CYCLE CONCEPT. THOUGH C A S E TECHNOLOGY IS A MATURE SOFTWARE TECHNOLOGY, THERE IS LTTTLE CHANGE IN THE LIFE CYCLE MODELS USED BY C A S E SINCE THE 'WATERFALL* MODEL WAS INTRODUCED [ B E R N 9 1 , B O E H 8 2 , H E N D 9 0 , YOUR79]. MOST OF THE SDLC MODELS ARE A DERTVED VERSION OF THE WATERFALL MODEL, AND ARE NOT REFLECTING THE C A S E BASED SOFTWARE PROCESS. IN THIS ARTICLE WE DEFINE A UFE CYCLE MODEL BASED ON THE USE OF C A S E TECHNOLOGY FOR THE SOFTWARE DEVELOPMENT PROCESS. THE SUGGESTED MODEL MAKES TT POSSIBLE TO MOVE FROM A SOFTWARE DEVELOPMENT LlFE CYCLE CONCEPT ( S D L C ) TO A SOFTWARE ENGINEERING LIFE CYCLE (SELC) CONCEPT. Software Development Life Cycle (SDLC) The software development life cycle concept, as a general concept is one of the basic ideas emerged from the field of software engineering. A life cycle model can be descriptive describe what exists, prescriptive prescribe what tasks need to be done, or normative establish standards [FREE87]. Considering the software process as an engineering process, life cycle model defines phases, tasks and a set of visible, intermediate products as the deliverable of those phases and tasks. The software development process can be defined at one of three levels [HUMP89]. A Universal (U) process model that provides a high level overview ,a Worldly (W) process model that describes the working level and an Atomic (A) process model that provides more details and refinements. In this articie we describe the software process at a U Universal and at a W Worldly level. Life cycle model was suggested as one of the early solutions to the software crisis by providing a consistent software development framework, but it turned out to be a partial solution that could not answer all of the problems of the software crisis. SDLC became the most basic concept in software engineering. Intensive research has been done in the area of SDLC models [ROYC70, BERN91, /f;' /S0' Page-1 v C •> Universiteit : . . . • • _•:.?: G.T. Vinig, J.S. Achtergerg CASE Technology from SDLC to SELC BOEH82, HEND90, YOUR79, DAVI88] Some of the software development life cycle models described in the literature are: The *Waterfair model The structured model Spiral Model Object Oriented model The importance of having a software development life cycle model was recognized, so there was the concern to find the 'right' or 'better' life cycle model. Some of the early research efforts were aimed at achieving this goal. As we are discussing models, it should be remembered that they are simple abstractions of reality, which help us to understand and describe the phases and tasks during the development process and the relationships betweenthem. But we should not expect to see models describing everything we experience in practice. As mentioned before, different models of the SDLC were developed since the introduction of the concept but, all of them contain, and are based on the foilowing three phases: ANALYZE O DESIGN OBUILD Most SDLC models are buiid around these main phases, using various levels of details and decompositions of tasks that make up each phase. The most used and referenced SDLC model is the traditional' or WaterfaH' model. Most CASE environments are using the waterfall model as the framework for the automation of the activities within the software process. The waterfall model describes the process as a Iinear set of tasks, where each task should be completed before the next starts. The completion criteria is a complete set of documents for the requirements, analysis and design phases. | 1 The 'Waterfall' Model of SDLC 1