Based on the different levels of services they offer,
data centers are categorized in 4 tiers, i.e. Tier I, Tier II, Tier III and Tier IV. The categorization describes the overall infrastructure of the data center required for running operations. While Tier I and Tier II are meant for tactical solution only that don’t offer much uptime, Tier III and Tier IV are more advanced and strategic solutions that offer more uptime, long term viability.
Availability offered by different levels of data centers: Tier I: 99.671%
Tier II: 99.741%
Tier III: 99.982%
Tier IV: 99.995%
Although Tier IV offers highest availability and long-term viability, it’s expensive and it is true that not all businesses require this much level of sophistication and elaborate mechanism. So significance of Tier III data centers are more, and most businesses opt to go with
Tier III data centers.
Tier III data center offers businesses a sophisticated infrastructure that allow higher availability, greater redundancy, and more reliability. Topology in Tier III data center can be maintained simultaneously that preclude the need of annual maintenance that could lead to shutdown of businesses.