The document discusses building an Infrastructure as a Service (IaaS) cloud using the Xen Cloud Platform (XCP). It describes the key components required, including hardware, networking, storage, hypervisor, service management, and user interface/API. It then outlines VMOps' cloud stack built on XCP, including its multi-site redundant deployment architecture and network and storage virtualization approaches. Finally, it notes some limitations of using XCP and opportunities for future enhancements.