Abstract
The federated cloud paradigm is getting popular for its dynamic allocation of resources, processing power, improved performance, and scalability. A federated cloud lets multiple cloud service providers collaborate and delegate services. However, this delegation requires pre-approval from domain administrators which can create an administrative bottleneck and cause serious delays in times of need. Despite the recent advancements in the field, the federated cloud environment still lacks an ad-hoc delegation method that allows its users to delegate their rights at runtime. Software Defined Network (SDN) provides an opportunity to enhance the performance of federated cloud in terms of delegating network services among different domains. This paper explores various characteristics of the SDN-driven federated cloud and proposes a delegation framework enhancing different important dimensions. Further, a fine-grained delegation model is developed that supports delegation within different cloud environments constituting the federated cloud. A CPN based simulation of the model is provided to rectify any ambiguities in its practical use. The model is also compared with existing models to emphasize its significance. The results reflect that various dynamics of the SDN-driven federated cloud can be efficiently addressed by the proposed model.