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Data center tiers

(also classification system)

Data center tiers definition

Data center tiers are rankings that showcase the performance of the servers. The Uptime Institute, a leading data center research and consulting organization, has developed a standardized methodology to measure and describe a data center's infrastructure's reliability, redundancy, and availability. Data centers are divided into four tiers: Tier I, Tier II, Tier III, and Tier IV. Each represents a progressively higher level of infrastructure reliability and availability.

See also: data breach, backup

Data center tiers types

  • Tier I. It is the lowest-rated tier and provides essential capacity but lacks IT components that support redundancy. Tier I data centers come with an uptime of 99.671%, which is particularly low for a competitive website. It translates to 28.8 hours of downtime per year.
  • Tier II. Compared to the first tier, this one has a better uptime of 99.741%, or around 22 hours of downtime per year. It saves data center operations as backups and can restore them in case of data breaches, which makes the system more reliable.
  • Tier III. This tier has an uptime of 99.982%, or around 1.6 hours of downtime per year, and it implements the N+1 redundancy option, indicating an extra component for supporting a system failure.
  • Tier IV. The last tier has the highest expected uptime of 99.995%, or less than 26 minutes of downtime per year, allowing users to monitor the system the whole time. It also has a fully redundant infrastructure with the 2N component. As a result, no matter what happens to the data center, it creates an exact replica for every part, making it the strongest security form.