The non-functional requirements are those aspects of the IT system that, while not directly affecting the business functionality of the application but have a profound impact on the efficiency and effectiveness of business systems for end users, as well as the people responsible for supporting the program.
The definition of these requirements is an essential factor in developing a total customer solution that delivers business goals. The non-functional requirements (NFRs) are used primarily to drive the operational aspects of the architecture; in other words, to address major operational and technical areas of the system to ensure the robustness and ruggedness of the application.
Benchmark or proof of concept (POC) can be used to verify if the implementation meets these requirements or to indicate if a corrective action is necessary. Ideally, a series of tests should be planned that maps to the development schedule and grows in complexity.
The topics that are covered in this chapter are as follows:
- Definition of NFRs
- NFR KPI and metrics
