Task Oriented Web Service Requirement Framework

Aiming to overcome the mismatch between coarse grain of Web service's functions and fine grain of current Web service requirements with inputs and outputs as functional requirements, a three layer task oriented Web service requirement framework is proposed. The top the is task layer which defines the tasks and their relationships, the middle is the method layer which represents multiple implementations of the primitive task, and the low is the operation layer which represents the abstract features of typical operations that a method owns. The task oriented Web service requirement framework proposed well matches the coarse grain feature of Web service's functions and provides a more natural way to express the service requirements.