This thesis will explore and investigate the possibility of implementing nested clouds to increase flexibility. A nested cloud is a private cloud running inside another private or public cloud. The goal is to enable live migration of virtual machines across cloud boundaries.
A virtual machine running in a cloud on top of a hypervisor could not traditionally be migrated to a different cloud using a different hypervisor. This creates boundaries and lock-in situations with loss of flexibility. By nesting a cloud it can span multiple different clouds and hypervisors to create a virtual private cloud. The various underlying platforms will then act similar to different physical server nodes in a traditional cloud.
An implementation using nested clouds was suggested and tested as an evolution of the private hybrid cloud. The working implementation could be a solution to the increasing importance of cloud independence. For the nested cloud to be feasible it is required that the overhead by having virtualization on two layers is kept at a minimum. Throughout the thesis the performance was measured and analysed to maintain a high performing system, and the behaviour was observed to ensure robustness.