Tier 1 Storage
For business-critical 24x7 databases; file servers and email applications; and data warehouses; a redundant, cache-based tiered storage model—called tier 1 storage—is the best option. The tier 1 storage model offers quick response time and fast data transfer rates. As such, tier 1 storage is a great solution for companies that need to effectively store high performance data that demands high availability.

Tier 2 Storage
For seldom-used, non-critical databases—historical data for instance—a tier 2 storage model is a great option since tier 2 data can generally be stored on less expensive media in storage area networks (SAN). Tier 2 storage is a good solution for organizations that have a large amount of data that doesn't require 24x7 availability or extensive backup. Tier 2 storage can also help reduce hardware costs and management overhead.

Tier 3 Storage
For rarely accessed data, a tier 3 storage model offers further economies of scale since data can be stored on even less expensive media such as recordable compact discs. Tier 3 storage is a convenient and simple way for IT administrators to protect large amounts of non-critical data from fire, theft, and computer malfunctions.