Service-oriented architectures (SOA) are based on a paradigm that aims at facilitating the management of business processes.
Services are business relevant functionalities that are transparently provided by one or more applications. This simplified
view on SOA has little in common with the view on technical and non-functional system properties from the high-availability
research area.
After the presentation of service examples taken from various research approaches this position paper introduces a service
layer model delimiting the notion of services. It is shown that specific layers of this model can help to determine and increase
the availability of business processes. Furthermore the usability of service composition is questioned. The outlook in the
last section of this position statement dares to predicts a shift from service-orientation to event- and business-orientation.