Requirements on Quality Specification Posed by Service Orientation

As service orientation is gaining more and more momentum, the need for common concepts regarding Quality of Service (QoS) and its specification emerges. In recent years numerous approaches to specifying QoS were developed for special subjects like multimedia applications or middleware for distributed systems. However, a survey of existing approaches regarding their contribution to service oriented QoS specification is still missing. In this paper we present a strictly service oriented, comprehensible classification scheme for QoS specification languages. The scheme is based on the MNM Service Model and the newly introduced LAL–brick which aggregates the dimensions Life cycle, Aspect and Layer of a QoS specification. Using the terminology of the MNM Service Model and the graphical notation of the LAL–brick we are able to classify existing approaches to QoS specification. Furthermore we derive requirements for future specification concepts applicable in service oriented environments.