Data availability

Data availability is a term used by computer storage manufacturers and storage service providers (SSPs) to describe products and services that ensure that data continues to be available at a required level of performance in situations ranging from normal through "disastrous."

Anytime a server loses power, for example, it has to reboot, recover data and repair corrupted data. The time it takes to recover, known as the mean time to recover (MTR), could be minutes, hours or days.

The two organizations in the United States that publish data center standards are the Telecommunications Industry Association (TIA) and the Uptime Institute.

Tier I Requirements

Tier II Requirements

Tier III Requirements

Tier IV Requirements

The Uptime Institute’s tier system allows for the following minutes of downtime annually:

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