Wibke Michalk


The rise of Software as a Service (SaaS) platforms is driven by the current trend towards customeroriented, agile and scalable service provisioning. Customers’ demand for highly specialized services can mostly not be met by a single provider that offers a holistic solution but by a consortium of providers that cooperate. In order to enable the combination of services and hence, the collaboration between different service providers, technical challenges like the compatibility of interfaces have to be dealt with. In addition, economic issues concerning profit, reliability and risk of service failure have to be taken into consideration. A model of Agreement Networks (ANs) is presented that illustrate the legal bindings that are established or under negotiation between service providers and a methodology is introduced that supports providers in ANs to decide on the establishment of a combination of Service Level Agreements (SLAs) that incurs the lowest risk of SLA violation. Finally, a benchmark for risk-based decisions is derived that serves to evaluate the efficiency of the choice. The impact of the available amount of monitoring data on the decision is investigated and a minimal amount of 100 observations for each SLA combination is suggested.