• Americas

      Count on quality and consistent customer services across more than 290 data centers in North and South America.

    • EMEA

      Harness cloud and carrier-neutral data center, colocation, and interconnection solutions across Europe and Africa.

    • Customer Stories

      • XTREME-D

        Find out how XTREME-D was able to meet its objectives and has positioned itself for further growth by partnering with Digital Realty and leveraging PlatformDIGITAL®.

        Keep Reading
      • Telefónica UK

        See how they leveraged PlatformDIGITAL™ Data Hub to localise data aggregation, staging, analytics, streaming and data management to optimise data exchange and maintain data compliance.

        Keep Reading
      • Criteo

        By partnering with a company like Digital Realty, Criteo has somebody who can work with them to ensure they move a long way towards their sustainability goals

        Keep Reading
      • Join Digital

        With increasing demand for a turnkey experience, Join™ helps their customers brings the built and digital worlds together with the essential Network-as-a-Service and IT-as-a-Service offerings for Smart Buildings and Smart Workplaces.

        Keep Reading
      • AIB

        AIB, Inc., a leading data exchange and management firm serving over 1600 automotive customers, sought to diversify their cloud portfolio to realize reduced latency, increased availability, and harden security posture.

        Keep Reading
    • Global Data Insights Survey

      Read the survey

    • Investor Relations

      Digital Realty owns, acquires, develops and operates data centers. The company is focused on providing data center, colocation and interconnection solutions for domestic and international customers.

    • NYSE: DLR

      $129.83

      +1.75 (+1.35%)
      * Previous Day's Close
    • Investor Relations
    • Leadership
Hero_Blog_5000x1800_Data Center Tiers

What are Data Center Tiers and How Are They Rated

What are Data Center Tiers?

The data center tier system was designed by the Uptime Institute to classify data centers based on a number of criteria relating to uptime, fault tolerance and availability primarily. The tier system is intended to give businesses an independent understanding of how a particular data center facility will function per their needs and what they might be able to expect from the location.

The Uptime Institute has core standards segmented as tiers, and tiers are in a range from one to five. This global standard enables organizations to determine how any data center in the world compares to any other one. A final certification highlights a data center’s design, construction and operations.

What is a Tier 1 Data Center?

A tier 1 data center is the most basic kind of data center facility. A tier 1 data center has dedicated space for IT services and equipment outside of an office, an uninterrupted power supply, backup electrical power typically from an on-site generator and equipment to keep computing equipment cool. A tier 1 data center also has systems, protocols and equipment in place to ensure it is up and running beyond standard office hours (i.e. nights and weekends).

What is a Tier 2 Data Center?

A tier 2 data center contains everything that a tier 1 data center has, except it also includes redundant components for additional capacity. These components often include engine generators for backup power, pumps or chillers for additional and more reliable equipment cooling, and dedicated UPS modules for more reliable electricity free of sags and power spikes.

What is a Tier 3 Data Center?

A tier 3 data center includes everything found in a tier 2 data center, except it has systems, protocols and equipment in place to allow staff to make upgrades, fixes and/or changes without having to shut anything down. Because everything is concurrently available, teams can make any changes as needed without interrupting services to customers/end users.

What is a Tier 4 Data Center?

A tier 4 data center has everything found in a tier 3 data center, except it also includes fault tolerance mechanisms. The idea here is that the data center can stop and prevent certain issues from ever arising in the first place. The goal of a tier 4 data center is to provide continuous support and services no matter what, and is the highest classification provided by the Uptime Institute.

What is a Tier 5 Data Center?

A tier 5 certification is designed to denote a facility that meets the highest possible standards in the market today regarding uptime and resiliency. The tier 5 designation was initially developed by colocation and cloud provider Switch in 2017, and is technically separate from the four core tiers designated by the Uptime Institute.

What is the Best Tier?

According to the Uptime Institute, no one tier is considered “better” than the others. Rather, they note that businesses should choose a data center that meets their specific needs around cost, availability, etc.

What is the Uptime Institute?

The Uptime Institute describes itself as an independent advisory organization designed to provide third-party guidance and oversight to the data center industry. Part of its core mission includes overseeing data centers and assigning certifications, so that data center end users have verifiable guidance when deciding which facility to use. Like 451 Research, The Uptime Institute is a division of The 451 Group.

How are Tiers Assigned?

To determine which tier a data center falls under, facility management submits site plans and blueprints - otherwise known as Tier Certification of Design Documents - to the Uptime Institute. Once this step is completed, representatives from the Uptime Institute to go on site to see firsthand how the facility runs and the extent to which the actual, built facility aligns with initial planning documentation.

Architech image02 2021 12 17 134536 Architech image01 2021 12 17 134535 Architech image03 2021 12 17 134537

Future-Proof Your Digital Deployment

Connect with a Digital Realty Cloud Certified Solution Architect to help build your scalable growth strategy and transform your business.

Connect with Us