IaaS Service Selection Revisited

Cloud computing is a paradigm that has revolutionized the way service-based applications are developed and provisioned due to the main benefits that it introduces, including more flexible pricing and resource management. The most widely used kind of cloud service is the Infrastructure-as-a-Service (IaaS) one. In this service kind, an infrastructure in the form of a VM is offered over which users can create the suitable environment for provisioning their application components. By following the micro-service paradigm, not just one but multiple cloud services are required to provision an application. This leads to requiring to solve an optimisation problem for selecting the right IaaS services according to the user requirements. The current techniques employed to solve this problem are either exhaustive, so not scalable, or adopt heuristics, sacrificing optimality with a reduced solving time. In this respect, this paper proposes a novel technique which involves the modelling of an optimisation problem in a different form than the most common one. In particular, this form enables the use of exhaustive techniques, like constraint programming (CP), such that both an optimal solution is delivered in a much more scalable manner. The main benefits of this technique are highlighted through conducting an experimental evaluation against a classical CP-based exhaustive approach.