Use cases based requirements validation with scenarios

Use cases are analytical descriptions of how a system should react in interaction with actors. Use cases are appropriate as specification of a system required behavior. A scenario is an example of execution of a system that may be defined with the intention that it should be supported or the intention that it should be avoided. As such, scenarios are appropriate for requirements validation. This paper presents an approach where use cases and scenarios are used to complement each other for requirements engineering. Use cases define what a system should do, and scenarios are used to validate use cases.