requirments engineering

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requirments engineering

Systems analysts should carefully record and document factual information as it is collected, and various software tools can help an analyst visualize and describe an information system.

Requirements V&V is concerned with demonstrating that the requirements define the system that the customer really wants. Validation asks if the correct requirements are stated, while verification asks if the requirements are stated correctly.

All requirements engineering activities can be helped through the judicious use of tools. They provide automated support for requirements attributes such as traceability. For very large systems with thousands of requirements to manage, CASE tool assistance is necessary.

Systems analysts use various tools and techniques to represent system requirements. Natural language, structured or unstructured, is still the default. Requirements can be stored as simple text in a plain file or in an Excel spreadsheet. They can also be stored online for automated search and analysis.

Diagrams are another way of representing requirements. They are suitable for analysts who are more visually oriented. They can also capture complementary aspects of the system requirements. Sample diagram types include FDDs, business process diagrams, and DFDs.

Models provide a more formal representation of system requirements. The UML is a widely used method of visualizing and documenting software design through the eyes of the business user. UML tools include use case diagrams and sequence diagrams to represent actors, their roles, and the sequence of transactions that occurs.

RAD is a team-based technique that speeds up information systems development and produces a functioning information system. RAD is a complete methodology, with a four-phase life cycle that parallels the traditional SDLC phases.

Agile methods attempt to develop a system incrementally by building a series of prototypes and constantly adjusting them to user requirements. Tools are often avoided and replaced with simpler aids, such as whiteboards and sticky notes to facilitate communication.

The requirements gathering process includes interviewing, document review, observation, questionnaires, sampling, and research. Successful interviewing requires good planning and strong interpersonal and communication skills. The systems analyst must decide on the people to interview; set interview objectives; and prepare for, conduct, and analyze interviews. The analyst also might find it helpful to use one or more software tools during fact-finding.

During requirements engineering, the business-related requirements for the new information system are identified. Scalability is considered to ensure that the system can support future growth and expansion. Security is an essential requirement of all modern connected systems. The TCO is also estimated to identify all costs, including indirect costs.

Popular team-based approaches include JAD, RAD, and agile methods. JAD is a popular, team-based approach to fact-finding and requirements engineering. JAD involves an interactive group of users, managers, and IT professionals who participate in requirements engineering and develop a greater commitment to the project and to their common goals.

The systems analysis phase includes three activities: requirements engineering, data and process modeling, and consideration of development strategies. The main objective is to understand the proposed project, ensure that it will support business requirements, and build a solid foundation for the systems design phase. Requirements engineering itself is composed of three main parts:

gathering requirements

representing requirements