A Taxonomy for Identifying and Specifying Non-Functional Requirements in Service-Oriented Development

As in traditional software development, non-functional requirements play also a crucial role in service-oriented development. Non-functional requirements are spread across the entire service-oriented system or within individual services and cannot be allocated to one specific system / service artefact (such as a package, component). This makes them often more difficult to handle than functional requirements. The specifics of service-oriented architectures (in particular highly distributed services) bring up additional difficulties. In this paper, we present a taxonomy for non-functional requirements in a service-oriented context. The taxonomy implements three main categories of non-functional requirements: process requirements, non-functional external requirements, and non-functional service requirements. The taxonomy can be applied with individual services as well as with a service-based system as a whole. This taxonomy is considered as a starting point and check list when handling non-functional issues in service-oriented and particularly highly distributed environments.