SLA management - challenges in the context of Web-service-based infrastructures

This paper gives a first insight in an ongoing investigation. Our generic aim is to describe the current situation of available Web services in context with their quality of service (short QoS) behavior. The current quality behavior of offered Web Services should be evaluated in particular as an important aspect of an effective service level management. After providing an introduction to Web service technology, this contribution primarily aims to describe the topic of service level agreements (short SLA) management in such environments. In this context, we will highlight the general contents of SLA agreements, describe the interaction chain for service provision that arises in Web-service-based solutions, and provide a brief explanation of the opportunities offered by the WSLA framework that IBM has developed especially for Web services. Finally we describe the conception, prototypical development and the possible application of a measurement service for monitoring the quality behavior of a specific Web service. This measurement service can be used to support service level agreements.