VMware Cloud Director relies on vSphere resources to provide CPU, memory, and storage to run virtual machines. In addition, starting with version 9.7, VMware Cloud Director can act as an HTTP server between tenants and the underlying vSphere environment.
For information about VMware Cloud Director system requirements and supported versions of vCenter Server and ESXi, see the VMware Product Interoperability Matrixes at http://partnerweb.vmware.com/comp_guide/sim/interop_matrix.php.