Data Center Tier Levels

by | Data Centers

How Tier 1, Tier 2, Tier 3 and Tier 4 Data Center Levels Affect Your Business?

Uptime or data center availability is a critical factor that is considered by businesses when leasing data center colocation space. Data centers have different infrastructure design topologies which act as a basis for uptime Tiered classification system.  The uptime Tiered classification system of data centers are specifically developed to addresses the industry’s need for benchmarking standards.  The Tier system is divided into four categories which include the following

  • Tier 1 – Basic site infrastructure and not redundant
  • Tier 2 – Some redundant capacity components
  • Tier 3 – Concurrently maintainable infrastructure
  • Tier 4 – Very fault tolerant infrastructure

The Tier system is useful to measure different metrics such as Data Center performance, Investment and Return of Investment.  The Uptime institute is the authority body that decides the specification and conditions applicable to different Tier systems for Data Centers. The Uptime Institute is also called as “The Global Data Center Authority”. 

Data Center Tier LevelsThe Telecommunications Industry Association’s TIA-942 Telecommunications Infrastructure Standard for Data Centers specifies the minimum requirements for telecommunications infrastructure of data centers and computer rooms. This includes single tenant enterprise data centers and multi-tenant Internet hosting data centers. The Uptime Institute LLC is a consortium of companies that engage in consulting and IT services for the enterprise data center industry and for data center professionals. It is best known for its widely used certification and adoption of tier certifications of data centers.

Data Center Tier Levels

Tier 1

  1. Data Center with Tier 1 certification has basic no or minimal redundancy.  The yearly downtime is around 28.8 hours.
  2. Uptime guarantee is around 99.671%.
  3. The Tier 1 is suitable for small businesses which do not have critical mission applications.
  4. Planned or unplanned outages or failure in mechanical and plumbing systems (MEP) can result in negative impact on data processing equipment.
  5. There are no redundant components for power and cooling.

Tier 2

  1. Data Center with Tier 2 certification has some redundant components.
  2. The yearly downtime is around 22 hours and meets or exceeds all Tier 1 requirements.
  3. Enough redundant site infrastructure capacity to support an Uptime guarantee is around 99.741%.
  4. Tier 2 certified Data centers offer some redundancy in Power and cooling.

Tier 3

  1. Data Center with Tier 3 certification has redundant power components.
  2. The yearly downtime is around 1.6 hours
  3. Meets or exceeds all Tier 1 and Tier 2 Uptime guarantees and is around 99.982%
  4. Data center with Tier 3 certification is the target for most new data centers and is ideal for medium to large businesses.
  5. Tier 3 certified data centers have 72 Hour Power Outage Protection

Tier 4

  1. Data centers with Tier 4 certification  offer the best data center redundancy
  2. The yearly downtime is around 2.4 minutes
  3. Uptime guarantee is around 99.995%
  4. Data center with Tier 4 certification is ideal for Enterprise corporations
  5. Tier 4 certified data centers have 96 hour power outage protection.
  6. This is the most expensive type of data center. There are very few Tier 4 data centers in the world and most of them are private data centers.

Data centers with Tier 1 and Tier 2 certification have one active distribution path while Tier 3 has one active and alternate distribution path which reduces the probability of downtime.   Tier 4 Data center has 2 active distribution paths which mean the probability of downtime is almost eliminated. Even if one distribution path fails due to some reason, there is always an alternate distribution path active which invariably means your customers will be always able to access your site round the clock, 365 days a year. Both distribution paths in Tier 3 and 4 can undergo concurrent maintenance without disturbing your business activities.

Why seek a data center colocation consultant?

The specifications related to different Tier levels given above are just outlines of the Data center infrastructure. Businesses looking for colocation need to seek the service of the experts in the field in order to select a best data center. Fractional tier ratings advertised by some data centers do not exist in real scenario, so businesses not seeking data center consulting may end up paying more for a less Tiered data center. Also, businesses generally enter into a long-term contract while buying data center space which may prove an obstacle in selecting best data center resulting in excess expenditure over a long period.  Data center colocation consulting services have profound knowledge about the compliance, security and regulatory issues pertaining to operating a data center, so going by expert advice is always advised when your brand name is at stake.

DataCenterAndColocation,, is one of the largest colocation site consulting firms in the United States. They represent approximately 3000 data centers and colocation centers. At no cost to clients, they identify specific space, location, power and security requirements, solicit proposals, professionally analyze the responses, compare the strengths and weaknesses, negotiate pricing and deliver highly competitive bids for colocation. They also perform comparative analysis for in-house vs. design build services, wholesale data center space and data connectivity.