Selection of Cloud Service Providers for Hosting Web Applications in a Multi-cloud Environment

With the evolving data regulations and residency laws, it is becoming challenging for enterprises to serve all the geographically distributed users. To abide with the regulations and to leverage the benefits, such as good quality of service at a low cost, and avoid vendor lock-in, enterprises are seeking multiple Cloud Service Providers (CSPs) for hosting their web applications. The selection of CSPs in a multi-cloud environment is a challenging problem as it depends on multiple criteria such as security, service cost, manageability and so on. In this paper, we address the CSP selection problem for multiple applications in a multi-cloud environment comprising of multiple criteria. We provide a holistic solution methodology that ranks the CSP combinations for each web application using a multiple-criteria decision-making (MCDM) technique. The solution methodology takes virtual machine and cloud center selection into consideration for ranking the CSP combinations. However, selecting the top ranked CSP combinations for all applications may not be a viable option from the manageability and budget perspectives. Hence, we propose an optimization model to select CSPs for multiple applications of an enterprise considering budget and rank. We demonstrate our methodology through numerical experiments and provide various insights.