Utility storage is a service model in which a provider makes storage capacity available to an individual, an organization or a business unit on a pay-per-use basis. The utility model is sometimes called metered services or storage on demand.
As in the utility computing model, the purpose of utility storage is to use resources efficiently and reduce costs. A use-based pay structure can be much more cost-effective for an enterprise than it would be for them to purchase, manage and maintain an infrastructure that meets peak requirements, which may be far beyond what’s needed normally.
There are three basic models of utility storage:
- On demand. Vendors install storage systems configured with more capacity than is needed; users "turn on" additional capacity as required and are billed for the additional usage.
- Internal utility. In this scenario, an IT department pools its storage resources and adds the components necessary to internally administer the storage as an on-demand service to the company's business units.
- Off site. Storage service providers (SSPs) provide off-site storage facilities, typically based on a lease arrangement with service level agreements (SLAs) that guarantee quality of service (QoS). Many companies use SSPs for off-site backup; increasingly, SSPs are also being used to replace or augment onsite data storage. See: storage as a service (SaaS)