Types of Software Requirements | software engineering.pptx

This presentation explain the types of requirements that which are collected for a software project. There are five types f requirements i.e. Functional, non-functional, domain, inverse and design and implementation constraints. Requirements explain what is needed in the software and are collected from stockholders.

1. Software Requirements (OOAD T utorial Series) By: UPSOL ACADEMY

2. Requirements ?

3. requirements must be complete and unambiguous. Incomplete and ambiguous requirements are open to multiple interpretations and assumptions This can lead to the development of poor quality, or faulty, software products Tips for Requirements

4. Source of Requirements

5. Functional Requirements Non-Functional requirements Domain Requirements Inverse Requirements Design and Implementation Constraints Requirements Types

6. Statements describing what the system does. Functionality of system Statements of services the system should provide Reaction to particular inputs Behavior in particular situations Customers and developers usually focus on functional requirements. Example: Login, Browse, Add to cart etc. Functional Requirements

7. Most non-functional requirements (NFRs) relate to the system as a whole. They include constraints on: Performance Reliability Security Maintainability Usability Standards More critical and may make system unusable if failed to apply.. Non-functional Requirements

8. Example: If a real-time control system fails to meet its performance requirements, the control functions will not operate correctly e.g. ATM in banking system. NFRs come up/depends through: User needs, budget & interoperability, Organizational policies(s/w developing), External factors such as safety regulations, privacy legislation, etc. Non-Functional Requirements

9. Architecture: where non-functional decisions are cast, and functional requirements are partitioned . Design : where functional requirements are accomplished Non-Functional Requirements Architecture vs design

10. requirements that come from Application domain Reflect fundamental characteristic of application domain. These can be both F unctional and Non-Functional requirements Domain requirements can impose strict constraints on solutions Domain Requirements

11. They explain what the system shall not do . Example: The system shall not use red color in the user interface, whenever it is asking for inputs from the end-user Inverse Requirements

12. They are development guidelines within which the designer must work. These requirements can seriously limit design and implementation options Can also have impact on human resources Example: Design and implementation Constraints

13. Example: The system shall be developed using the Microsoft .Net platform The system shall be developed using open source tools and shall run on Linux operating system Design and implementation Constraints