An Open Middleware for Proactive QoS-Aware Service Composition in a Multi-Tenant SaaS Environment

Business Process as a Service (BPaaS) is expected to emerge as the next major category of Cloud Computing. The combination of fast expanding technologies with increasing competitiveness will make more and more companies move parts of their business processes into the cloud. This enables them to take advantage of the cloud provider’s expertise and to reduce their cost by sharing resources to exploit economies of scale. In such a multi-tenant setting, the cloud provider has to tailor its business processes to meet the QoS requirements of each tenant. This requires techniques for QoS-aware service selection and prediction. However, there is no one-size-fitsall approach to tackle this challenge. The choice of the most suitable technique typically depends on the particular context and characteristics of the services that are being composed. This paper has the following contributions: To support the provider with the creation of custom-tailored processes, we propose an open middleware that provides the mechanisms to perform requirement-driven customizations on shared process templates. This open middleware supports easy integration of new and existing service selection and prediction techniques.