An Approach for Evaluating Cloud Application Topologies Based on TOSCA

Provisioning cloud applications usually is a complex task as it involves the deployment and configuration of several components (e.g., load balancer, application server, database) and cloud services (computing, storage, CDN, etc.) also known as application blueprints or topologies. The Topology and Orchestration Specification for Cloud Applications (TOSCA) is a recent standard that has focused on standardizing the way cloud applications are structured and managed to favor interoperability. In this paper we describe an approach that facilitates the evaluation of different application topologies by enabling cloud users to easily provision and evaluate different TOSCA topology options based on performance and cost metrics. We show the technical feasibility of the approach based on a case study with the WordPress blogging application where various topologies were automatically provisioned and evaluated in order to gain insights into the best (w.r.t. performance) options.