Towards conceptual foundations for service-oriented requirements engineering: bridging requirements and services ontologies

The engineering of a service-oriented system requires the specification of functions that Web services (WSs) should provide, before WSs are built or selected. Written in a service description language, the service specification instantiates concepts different than those used for requirement engineering (RE): the former speaks in terms of operations, metrics and bindings, whereas the latter manipulates, goals, evaluations and domain assumptions. It is, however, clear that functions expected of WSs to select or build will be relevant to the stakeholders if they satisfy the stakeholders' requirements. As a result, there is a gap between the two specifications which must be bridged in order to ensure that the WS system is adequate w.r.t. requirements. This study proposes mappings between the concepts of requirements ontology and those of service taxonomy induced by the WSLD and the WSLA languages. A working prototype is presented that implements the mappings and is used to translate the instances of RE concepts into instances of WSLD and WSLA concepts. The mappings and the prototype facilitate the engineering of WS systems, as fragments of WS descriptions can be generated from requirements as a first specification of a service request.