One of the most important features of the cloud is the sharing of resources by multi-tenants.

Without sharing and being able to optimize utilization of resources, the cloud operator can’t provide scalability and support “economies of scale” for its business.

The IaaS public contains its “cloud magic” as well as real hardware such as computing, storage, and network devices. The utilization of these resources should be optimized by meeting demand (by time), hence they must be shared between the cloud consumers.