cloud storage (p. 7): Cloud Storage delivers virtualized storage on demand, over a network based on a request for a given quality of service (QoS). There is no need to purchase storage or in some cases even provision it before storing data. You only pay for the amount of storage your data is actually consuming. (†777)
cloud storage (p. 8): The difference between the purchase of a dedicated appliance and that of cloud storage is not the functional interface, but merely the fact that the storage is delivered on demand. The customer pays for either what they actually use or in other cases, what they have allocated for use. In the case of block storage, a LUN or virtual volume is the granularity of allocation. For file protocols, a filesystem is the unit of granularity. In either case, the actual storage space can be thin provisioned and billed for based on actual usage. Data services such as compression and deduplication can be used to further reduce the actual space consumed. The management of this storage is typically done out of band of these standard Data Storage interfaces, either through an API, or more commonly, though an administrative browser based user interface. This interface may be used to invoke other data services as well, such as snapshot and cloning. (†778)
