Analysis gathers the requirements for the system. This stage includes a detailed study of the business needs of the organization. Options for changing the business process may be considered. Design focuses on high level design like, what programs are needed and how are they going to interact, low-level design (how the individual programs are going to work), interface design (what are the interfaces going to look like) and data design (what data will be required). During these phases, the software’s overall structure is defined. Analysis and Design are very crucial in the whole development cycle. Any glitch in the design phase could be very expensive to solve in the later stage of the software development. Much care is taken during this phase. The logical system of the product is developed in this phase.
More Details on System Analysis:
Requirements Analysis is done in order to understand the problem for which the software system is to solve. For example, the problem could be automating an existing manual process, or developing a completely new automated system, or a combination of the two. The emphasis in requirements Analysis is on identifying what is needed from the system and not how the system will achieve it goals. This task is complicated by the fact that there are often at least two parties involved in software development – a client and a developer. The developer usually does not understand the client’s problem domain, and the client often does not understand the issues involved in software systems. This causes a communication gap, which has to be adequately bridged during requirements Analysis.
In most software projects, the requirement phase ends with a document describing all the requirements. In other words, the goal of the requirement specification phase is to produce the software requirement specification document. The person responsible for the requirement analysis is often called the analyst. There are two major activities in this phase – problem understanding or analysis and requirement specification in problem analysis; the analyst has to understand the problem and its context. Such analysis typically requires a thorough understanding of the existing system, the parts of which must be automated.
Once the problem is analyzed and the essentials understood, the requirements must be specified in the requirement specification document. The requirements documents must specify all functional and performance requirements, the formats of inputs, outputs and any required standards, and all design constraints that exits due to political, economic environmental, and security reasons. The phase ends with validation of requirements specified in the document. The basic purpose of validation is to make sure that the requirements specified in the document, actually reflect the actual requirements or needs, and that all requirements are specified. Validation is often done through requirement review, in which a group of people including representatives of the client, critically review the requirements specification.