Rapid elasticity.Capabilities can be rapidly and elastically provisioned, in some cases automatically, to quickly scale out and rapidly released to quickly scale in. To the consumer, the capabilities available for provisioning often appear to be unlimited and can be purchased in any quantity at any time. Measured Service.Cloud systems automatically control and optimize resource use by leveraging a metering capability3at some level of abstraction appropriate to the type of service (e.g., storage, processing, bandwidth, and active user accounts). Resource usage can be monitored, controlled, and reported, providing transparency for both the provider and consumer of the utilized service. 2NIST Special Publication 800-145, The NIST Definition of Cloud Computing, -145/Draft-SP-800-145_cloud-definition.pdf3Typically through a pay-per-use business model.