Cloud Services Security Evaluation for Multi-Tenants

Cloud computing is witnessing a fast development and widespread adoption due to its cost-effective and resource efficient services. Nevertheless, security risks are not outsourced and remain under both cloud service providers and consumers responsibility. One of the main challenges is how to evaluate the security level of cloud services. Current methods are mostly focused on solving the problem of cloud services evaluation from a single user perspective. However, cloud computing is a multi-tenant environment that serves a large number of tenants with multiple end-users at the same time. This heterogeneity leads to different, and often, conflicting security requirements. In this paper, we propose a multi-tenant cloud services evaluation framework, whereby service selection is carried out per groups of tenants rather than per a single user. To ensure that all tenants' requirements are satisfied, we first consider the similarity between cloud service providers performances and tenants' requirements. Tenants' weights are determined in an objective way based on their risk attitudes and contributions to the overall group decision using fuzzy TOPSIS technique. The final ranking of the alternatives is further guided by consensus analysis process to guarantee a final solution with the highest level of agreement.