Computer storage manufactures and service providers use the term data availability to describe the products and services they offer to ensure that the data is always available to their customers instantly at the same speed at times of disasters as it is available in normal circumstances. Data availability is a term also used to describe the reliability of the data storage solutions services of a provider to the businesses. It is also a way to confirm the up-time guarantee and the quantity of data that can flow in a stipulated time. Storing data externally has removed the risks of data being lost due to hardware crashes or system getting corrupt.
Data availability is provided in different ways with the most popular ways being the network attached storage (NAS) or storage area network(SAN). The hardware used in these external storage systems is far more powerful and reliable and many providers also ensure higher availability by using multiple systems to store the same data. This guarantees data availability even at times if one of the components fail and reduces dependency on one single system.