Understanding how data centers are classified

3d computer servers in perspective Your business may one day face a difficult decision–what should I do with my data? There are pros and cons of storing and managing your own data. And for some the thought of housing their data somewhere else is a little frightening.

After spending a little time online I discovered one of the big questions businesses have when faced with this decision is how safe will their data be if they store it offsite?

This is without doubt a justifiable question. I can easily put myself in the shoes of the business owner and see their concerns like, what happens in the case of a fire? What security measures are in place? And what happens if power to the data center is interrupted for whatever reason?

A lot of these questions can be answered by looking at a data center’s tier.

The Telecommunications Industry Association and Uptime Institute have developed two of the most widely used data center classification models. The models are used to rate or grade data centers. The Telecommunications Industry Association calls its model TIA-942 and it’s based on the Uptime Institute’s tier classification system. Both systems have four tiers. The higher the tier, the less downtime a data center will experience each year.

Tier 1 data centers are the least reliable and Tier 4 data centers are the most. A Tier 1 data center could be something as simple as a storage closet with a rack of computer equipment. There would only be one power and cooling system in place.

A Tier 4 data center is made up of multiple active power and cooling distribution paths, it has several backups (also known as redundant components) and can withstand all types of disasters both natural and man-made. Tiers 2 and 3 fall in the middle.

One of the more noticeable differences between the two models is Uptime uses Roman numerals (I, II, III, and IV). The Uptime Institute also certifies data centers in three areas–design documents, constructed facility and operational sustainability. Data centers have to pay to be certified by the Uptime Institute.

TDS Hosted & Managed Services, LLC (TDS HMS), which consists of OneNeck IT Services Corp., Vital Support Systems, and VISI Inc., has seven data centers in four states. Here’s a breakdown of their tiers. Also, I’ve included a graph below that gives the basics of each tier.


06-21-13 Data Center Tiers Explained

Did this help you understand how data centers are classified? Leave your comments below and don’t forget to subscribe to this blog. If you have any questions, concerns or ideas for posts you can email me or contact me on twitter @BarclayPollak.

About Barclay Pollak

Barclay Pollak is an award winning journalist and proud to be a member of the Corporate Communications team at TDS Telecommunications Corp. (TDS®) in Madison, Wis. Barclay joined the team in April of 2013. Before that Barclay worked as an Anchor/ Reporter for the NBC affiliate in Madison. While at NBC-15 Barclay was recognized by several organizations for his contributions to the television news industry. They include the Wisconsin Broadcasters Association, the Radio Television Digital News Association (Edward R. Murrow Regional Award) and the Chicago/Midwest National Academy of Television Arts and Sciences (2012 Emmy Nominee). When he’s not working Barclay enjoys cheering for all the sports teams in Wisconsin. Barclay’s a University of Wisconsin-Madison alumnus and a huge fan of Badger athletics. Barclay is fascinated by the ever changing world of technology and spends a fair amount of his free time reading about the latest and greatest developments online. When Barclay’s not learning about technology he’s scouring the Internet in search of freeware. Barclay has an 8-year-old daughter and lives with his girlfriend of almost five years on Madison’s southwest side. Follow on G+.

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