| The System Development Life Cycle There are many methods for creating software applications. Some management teams swear by certain methods, and some of that mentality is quite true. But it's not a "one size fits all" world. Many methods have been developed over the years, and as applications get VERY complicated, there has to be a common way to keep all the parts glued together. System Development Life Cycle (SDLC) methodologies are mechanisms to assure that software systems meet established requirements (DOJ, 2000). These methodologies impose various degrees of discipline to the software development process with the goal of making the process more efficient and predictable. Shrinking cycle times are commonplace in the software industry. Software developers strive to reduce cycle times because of the competitive advantages provided and the greater number of products they are able to release in the same amount of time. However, time-to-market concerns have forced many developers to make conscious trade-offs between cost, quality, and features. In addition, aberrant development practices have arisen in spite of their negative effects on reliability, quality, morale, and process management. A number of system development life cycle (SDLC) models have been created: waterfall, fountain, spiral, build and fix, rapid prototyping, incremental, and synchronize and stabilize. The oldest of these, and the best known, is the waterfall: a sequence of stages in which the output of each stage becomes the input for the next. These stages can be characterized and divided up in different ways, including the following: Planning Can we build it? Will it provide business value? If we build it, will it be used? The system request and feasibility analysis are presented to an information systems approval committee (sometimes called a steering committee), which decides whether the project should be undertaken. Miss this step, you will probably build something no one will use, and waist a lot of money. Analysis Who will use the system? What the system will do? Where and when it will be used? Skip the analysis step, and you will build something that no one will have any clue on what you are building, why you are building it and what is going to be expected when you are done. Design How the system will operate? The design phase decides, in terms of the hardware, software, and network infrastructure; the user interface, forms, and reports that will be used Skip this step, and you are building your application without a blueprint. Interesting to see what actually is delivered. Implementation The final phase in the SDLC is the implementation phase, during which the system is actually built (or purchased, in the case of a packaged software design). This is the phase that usually gets the most attention, because for most systems it is the critical part of the development life cycle. Skip this step, and you don't get anything delivered. Reference: http://www.usdoj.gov/jmd/irm/lifecycle/table.htm - By David Ephraim of Atak Interactive, Inc. |