Systems Development Life Cycle - Coursework Example

Systems Development Life Cycle Section Number of Systems Development Life Cycle Systems Development Life Cycle (SDLC) is a detailed guideline that describes step by step how any system should be developed right from the project conceptualization phase to the system closure stage. When applied to software development SDLC defines in detail the entire software development process. The unprecedented development of Information and Communication Technology (ICT) in the last couple of decades has resulted in the adoption of computer infrastructure and implementation information systems and networks by almost all organizations worth its while. The ICT infrastructure of every organization has grown in scale and complexity with the passing years. This is more so in the case of large organizations that span across countries or continents. Software development has to take into consideration all aspects and all complexities of the system and organization for which the software is being developed. It is come to a stage where it is simply impossible to develop a software system independently and implement it over a complex and sophisticated infrastructure. Systematic and detailed study of the system and its requirements, a proper understanding of the various processes involved, anticipation of the changes and process re-engineering that would be called for, financial implication s and risks involved are essential for successful software development. This in turn warrants the involvement of a variety of ICT professionals in diverge fields of specialization who have to work according to a highly specified and detailed roadmap in order to achieve their objectives. Such a roadmap which gives in detail all the phases of the software development process so that it can be carried out smoothly without any hitches is known as the SDLC. Software systems development is not a very old profession from the historical perspective. Commercial applications development started off only in the early 1960s. Applications development in the early days did not follow any systematic technique. But by late 1960s it was clear that a more disciplines approach was required. “What evolved from these early activities in improving rigor is an understanding of the scope and complexity of the total development process. It became clear that the process of creating systems required a system to do systems. This is the SDLC. It is the system used to build and maintain software systems.” (Bender, 2003) There are different models of SDLC. These include waterfall, fountain, spiral, build and fix, rapid prototyping, incremental, and synchronize and stabilize. The waterfall model is the oldest amongst them, and is characterized by a sequence of stages in which the output of each stage becomes the input for the next. Objectives of SLDC SDLC has three core objectives: ensuring high quality, providing strong management control and maximizing productivity. Quality of a software system can either be judged in the context of business or in a context intrinsic to the software system itself. In a business context, quality is primarily defined in terms of the Return on Investment (ROI) achieved by the software system. The logic is very simple. The money spent in developing and ruining the software system could have been spent many other things such as advertising, product development and staff raises which could also have resulted in an increase in ROI. The quantitative measure of the quality of the software system in the context of business is given by the increase in ROI that the software achieves over the other non-software measures that could also have affected an increase in the ROI. The implementation of a software system usually results in improved decision support for strategic, tactical and operational planning; operations cost savings or cost avoidance and improved product flexibility leading to a larger market share, which in turn lead to an increase in the ROI. The intrinsic quality of a software system depends on certain characteristics of the software system itself. The robustness of the system, to what extend it is defect or error free, how well structures it is and how well documented are some of the characteristics of the system that defines its intrinsic qualities. Obviously, the intrinsic qualities also reflect directly on the systems ability to ensure the best possible ROI. The second core objective of the SDLC is to provide the management with timely, complete and accurate information on the status of the project and the system throughout the development process so that strong management control is retained all along. Predictability and feedback are the essence of strong management control, especially when projects last for many months or years. Being able to accurately estimate how long the project would take, how much of resources would be required and how much it will cost accords predictability. It tells the management whether ROI will be achieved at all, and if it is, how long it will take to do so. The feedback process enables the management to keep a close watch on the progress of the project. SLDC puts the management in the driver’s seat by ensuring predictability and feedback. An overview of the SDLC process in the US House of Representatives (1999) shows how this works in practice: “The SDLC phases provide an excellent opportunity to control, monitor, and audit the systems development process, and ensure customer and user satisfaction. A feedback process supporting Business Process Improvement (BPI) and Business Process Reengineering (BPR) is critical to ensure the correct process or activity is the basis for the technical activity leading to systems engineering and automation.” The third objective of SDLC is to maximize productivity. The SLDC does this by ensuring that there is no duplicity of labor in the software development process, and by ensuring that the available staff of developers is as productive as possible with respect to the resources, time, and funds required to deliver a given amount of function. Productivity, therefore, is defined in two ways: one on what is being built, and the other on how much time, resources and money is being expended on building it. The first kind of productivity is obviously directly linked to the ROI concept. The SLDC must not only ensure a well-defined ROI, it must also ensure that the project being undertaken is the one with the maximum possible ROI potential. In the second case, productivity will depend to a great extent on how labor intensive the development process is. One way to maximize productivity in such as case is to incorporate automation, to take maximum advantage of computer assisted software engineering tools. It is the SDLC that ensures maximum automation. Phases of SLDC SLDC for software development involves ten well-defined phases: i. Initiation: Initiation is the phase in which the need for the software systems is identified and formulated. It usually originates in a problem or a set of problems to which some solutions are sought. A project manager is entrusted with the responsibility of developing a concept Proposal in which the problem will be identified and the rationale for the new system will be put forth. The Concept Proposal is considered and approved by the management whose approval is required for the project to move to the next phase. ii. System Concept Development: It is in this phase that the expectations from the software system are worked out and a definite conceptual shape is given to the software system. Various reports such as the Feasibility Study which examines whether the project will work or not, Cost/Benefit Analysis, System Boundary which defines the extent of the project, Risk Management Study, etc. are developed and put to the management for approval. iii. Planning Phase: Crucial decisions on work assignment and workload distribution, deliverables, including whether to go for standard or customized solutions are taken in this phase. iv. Requirements Analysis: Requirements are documented. Requirements in terms of development interfaces, functionality, level of proficiency of developers, space, hardware, development software are mapped out and documented. v. Design Phase: Detailed workable specifications are developed on the basis of the requirements. The actual design of the system takes shape. Documentation of the maintenance manual, training manual and operational manual starts at this phase. vi. Development Phase: This is the phase in which the actual development of the software system takes place. Debugging is an integral part of this phase along with the development of a contingency plan. vii. Integration and Testing Phase: In this phase formal testing and integration is done along with required documentation. It may involve testing of migration from an old existing system to a new system. viii. Implementation Phase: The new software system developed is put to work in a live and real-time situation. Previous data is migrated to the new system. A review of the implementation process is also done in this phase. ix. Operations and Maintenance Phase: This phase involves keeping the system running continuously. Necessary systems updates are incorporated if required. This phase is concerned with the day-to-day operation of the software system. x. Disposition Phase: Every system has a specified life and at some point of time turns obsolete. It is time for a new for advanced system to take over. A disposition plan is drawn up. It takes into consideration archival of system documentation, archiving of data and getting rid of old equipment. The Browser Experience Microsoft Corporation and Netscape Communications Corporations used the Synchronize and Stabilize method of SLDC when they worked as a joint team to develop the Internet Explorer and communicator (). This method of SDLC allows many teams to work efficiently in parallel. Both these giant corporations found common elements in the way in which both of them worked. Both companies had done what they called a ‘build’ or a nightly compilation of the entire project in which they brought together all the current components. Common release dates were established and considerable effort was put in stabilizing the code before it was released. An alpha version was released for internal testing, and a beta version for wider external testing as specified by the SDLC. Specifications were frozen at some point before the release and time allotted to fixing bugs. Tanks to SDLC, both the companies managed millions of lines of codes against the backdrop of specifications that kept changing and evolving over time. The SDLC specified frequent design reviews and strategy sessions with proper documentation. The System Development Life Cycle has also evolved adapting to the technological advances. However, the basic principle of SDLC remains the same – to provide ICT professionals a clear roadmap for any software system development. References -01 1. Kay, R., 2002, Quick Study: System Development Life Cycle. Computerworld Development, May 14, 2002 [Online] Available. http://www.computerworld.com/developmenttopics/development/story/0,10801,71151,00.html [October 29, 2007] 2. Bender RBT Inc., 2003, Systems Development Life Cycle: Objectives and Requirements, Bender RBT Inc. 3. US House of Representatives, 1999, System Development Life Cycle Policy [Online] Available. http://www.house.gov/cao-opp/PDFSolicitations/SDLCPOL.pdf [October 29, 2007] Read More