GLYPH<SM590000> Over provisioned ratio 

The ratio of provisioned capacity to usable capacity in the pool or system. 

GLYPH<SM590000> Provisioning limit - maximum provisioned capacity - over provisioning limit 

In some storage systems, restrictions in the storage hardware or configured by the user that define a limit the maximum provisioned capacity allowed in a pool or system. 

## Capacity licensing 

Capacity licensing is a licensing model that licenses features with a price-per-terabyte model. Licensed features are FlashCopy, Metro Mirror, Global Mirror, and virtualization. See also “FlashCopy” on page 803, “Metro Mirror” on page 807, and “Virtualization” on page 814. 

## Chain 

A set of enclosures that are attached to provide redundant access to the drives inside the enclosures. Each control enclosure can have one or more chains. 

## Challenge Handshake Authentication Protocol 

Challenge Handshake Authentication Protocol (CHAP) is an authentication protocol that protects against eavesdropping by encrypting the user name and password. 

## Channel extender 

A channel extender is a device that is used for long-distance communication that connects other storage area network (SAN) fabric components. Generally, channel extenders can involve protocol conversion to asynchronous transfer mode (ATM), Internet Protocol (IP), or another long-distance communication protocol. 

## Child pool 

Administrators can use child pools to control capacity allocation for volumes that are used for specific purposes. Rather than being created directly from managed disks (MDisks), child pools are created from existing capacity that is allocated to a parent pool. As with parent pools, volumes can be created that specifically use the capacity that is allocated to the child pool. Child pools are similar to parent pools with similar properties. Child pools can be used for volume copy operation. Also, see “Parent pool” on page 808. 

## Cloud Container 

Cloud Container is a virtual object that include all of the elements, components, or data that are common to a specific application or data. 

## Cloud Provider 

Cloud provider is the company or organization that provide off- and on-premises cloud services such as storage, server, network, and so on. IBM Spectrum Virtualize has built-in software capabilities to interact with Cloud Providers such as IBM Cloud, Amazon S3, and deployments of OpenStack Swift. 

## Cloud Tenant 

Cloud Tenant is a group or an instance that provides common access with the specific privileges to an object, software, or data source. 

## Clustered system (SVC) 

A clustered system, which was known as a cluster, is a group of up to eight SVC nodes that presents a single configuration, management, and service interface to the user. 

