Well, from a customer point of view it's just a regular hypervisor / guest setup.
The levels below are required to make an IaaS cloud look more like the datacenter. The underlying assumption is that the bigger flexibility you have in datacenter deployments is beneficial, especially when we talk about any application not specifically designed for the cloud.
The levels below are required to make an IaaS cloud look more like the datacenter. The underlying assumption is that the bigger flexibility you have in datacenter deployments is beneficial, especially when we talk about any application not specifically designed for the cloud.