25 Nov 2022

Data center tiers are classification levels used to quickly identify the complexity and redundancy of the data center infrastructure being utilized. Data center tiers are an efficient way to describe the infrastructure components at a business’s data center. Although a Tier 4 data center is more complex than a Tier 1 data center, this does not necessarily mean it is best suited for a business’s needs. While investing in Tier 1 infrastructure might leave a business open to risk, Tier 4 infrastructure might be an over-investment.

A Tier 3 data center is a concurrently maintainable facility with multiple distribution paths for power and cooling. Unlike Tier 1 and 2 data centers, a Tier 3 facility does not require a total shutdown during maintenance or equipment replacement. A Tier 3 facility requires all the components present in a Tier 2 data center; in addition, these facilities must also have N+1 redundancy, where “N” refers to the necessary capacity to support the full IT load and “+1” stands for an extra component for backup purposes.

N+1 redundancy ensures an additional component will start operating if the primary element runs into a failure or the staff removes the part for planned maintenance.

Tier 3 data centers also require a backup solution that can keep operations running in case of a local or regional power outage. The facility must ensure equipment can continue to operate for at least 72 hours following an outage. Tier 3 data centers have a significant jump in availability when compared to lower ratings. Customers that rely on a Tier 3 data center experience an expected uptime of 99.982% (1.6 hours of downtime annually).

If a company is experiencing frequent interruptions and increasing downtime, it could be worthwhile to upgrade to a more fault-tolerant system. Compared to Tier 1 and 2 facilities, Tier 3 data centers are ranked high in data center reliability as concurrent maintenance is built into the site’s topology. This inherently limits the effects of the disruption before it reaches IT operations. For mission critical For applications and systems, this increase in reliability could become critical and necessitate an upgrade from Tier 2 to Tier 3.

In a Tier 3 data center, multiple power circulation paths and capacity equipment are supplied with simultaneous energy. Unlike Tier 1 and Tier 2, these facilities require no shutdown when maintenance or replacement is needed, so IT operations will not be impacted.

A Tier 4 data center is an expensive option for businesses. It has all the requirements of Tiers 1, 2 and 3 and ensures that all equipment is fully fault resistant. Tier 4 data centers serve corporations and are packed with features such as 99.995% uptime (26.3 minutes of downtime annually) and 2N+1 fully redundant infrastructure. Since Tier 1 and 2 data centers might not be up to standard and cannot support complex features required by businesses due to their simpler infrastructure, Tier 3 data centers might come as an optimal choice as they are more affordable than Tier 4 data centers but still offer impressive features.

Typically, Tier 3 data centers are the ideal choice for large companies with complex IT requirements that need extra fail-safe features. Businesses that host critical and extensive databases, especially customer data, usually go for this tier. In terms of required effectiveness, efficiency, and infrastructure, Tier 3 is more productive and cost-effective. Some Tier 3 facilities are in fact more trustworthy than Tier 4 facilities due to the high-unwavering engineering assembled to train, document, give techniques, and appropriately distinguish the operational components of the data center.