When organizations plan to move key Business applications and services to a Data Center, the key term that is comes fore is the Tiering Standard. The Tiering of Data Center standards exists to evaluate the quality and reliability of a data center’s server hosting ability.
Data Center Tiering was introduced by Uptime Institute where the Data Centers were classified into 4 Tiers – Tier 1, Tier 2, Tier 3 and Tier 4. The classification is an indication of level of design or construction to a datacenter’s overall availability and system redundancy. Tier 4 ranking is the highest benchmark for of reliability of a data center.
Below are the key ingredients of 4 tiers of data Center (Tier 1, Tier 2, Tier 3 and Tier 4).
TIER 1 DATA CENTER –
- 99.671% Uptime
- no redundancy
- 28.8 Hours of downtime per year.
TIER 2 DATA CENTER –
- 99.749% Uptime
- Partial (N+1) redundancy of components
- 22 hours of downtime per year
TIER 3 DATA CENTER –
- 99.982 % Uptime
- Fault Tolerant (N+1) redundancy of components
- 1.6 hours of downtime per year
TIER 4 DATA CENTER –
- 99.995 % Uptime
- Fault Tolerant (2N+1) redundancy of components
- 0.04 hours of downtime per year
Below table enumerates How the 4 Tier Standards of Data Centers differ from each other –