Tag: non functional requirements in software engineering

In software engineering, non-functional requirements (NFRs) refer to the criteria that judges the operation of a system, rather than specific behaviors. These requirements are associated with how the system performs, rather than what the system does.

They’re often designed to improve the user experience and maintain the quality of the software product. NFRs are typically not related to specific functions or features but are crucial for professional, commercial, or industrial applications.

Here are some examples of non-functional requirements:

1. Performance Requirements: These specify the system’s speed, response time, reliability, resource usage, and scalability. For example, a requirement might state, “The system should handle 500 users concurrently with a response time of less than 2 seconds.”
2. Security Requirements: These dictate how the system should protect itself and the user’s information from external threats. For instance, “User data must be encrypted and secure against unauthorized access.”
3. Usability Requirements: These describe how easy it is for a user to learn and operate the system. A usability requirement might state, “The user interface must be intuitive and easy to navigate without extensive training.”
4. Availability Requirements: These specify the required system’s uptime and accessibility. For example, “The system should have an uptime of 99.9%.”
5. Scalability Requirements: These relate to the ability of the system to expand to meet increased usage. For instance, “The system must support an increase of 50% in the number of concurrent users over the next two years.”
6. Maintainability Requirements: These requirements deal with potential modifications like correcting faults, improving performance, or adapting to a changed environment. For instance, “The code should adhere to a clear coding standard to facilitate future maintenance.”
7. Portability Requirements: These requirements are related to the ease of moving the software product from one environment to another. For example, “The software must be compatible with both Windows and macOS.”
8. Compliance Requirements: These are legal or regulatory standards that the software must adhere to. For example, “The system must comply with the General Data Protection Regulation (GDPR).”

In any software engineering project, it’s crucial to take into account both functional and non-functional requirements to ensure the development of a robust, user-friendly, and efficient system.