The 21st Century Data Center: An overview

The 21st Century Data Center: An overview

Summary: Data centers range from on-premise facilities running traditional enterprise applications to massive outsourced installations offering a variety of cloud services. We examine the state of play in data center-land, and consider some of the trends that will shape its future.


How much data?
How much data flows through the world's data centers, and what are the trends? This question has been addressed since 2011 by Cisco, with its annual Global Cloud Index (GCI). In its 2012 report, using network data from 10 enterprise and internet data centers, Cisco forecasts that global data center traffic will reach 554 exabytes (EB) per month by 2016, up from 146EB (1 exabyte = 1,000 petabytes = 1,000,000 terabytes). In annual terms, that's a rise from 1.8 zettabytes (ZB) in 2011 to 6.6ZB in 2016 — a CAGR of 31 percent:

Data center traffic projections to 2016 (1 zettabyte = 1,000 exabytes). (Image and data: Cisco Global Cloud Index)

Where does all this data come from? Cisco divides data center traffic (both business and consumer) into three broad classes: traffic that remains in the data center; traffic that flows between data centers; and traffic that flows from data centers to users over the internet or IP WAN. According to Cisco, the majority (76 percent) of traffic is the kind that remains within the data center:

Only 17 percent of data center traffic is estimated to flow from data centers to users. (Image and data: Cisco Global Cloud Index)

When server workloads are considered, the momentum towards the cloud is clear, with Cisco estimating 180.6 million installed workloads in 2016, split 62/38 percent between cloud and traditional data centers, compared to 71.1 million workloads in 2011 with a 30/70 percent cloud/traditional split:

Server workload location projections to 2016 (a server workload is defined as the processing a server undertakes to run an application and support a number of users). (Image and data: Cisco Global Cloud Index)

The average number of workloads per physical server in cloud data centers is expected to grow from 4.2 in 2011 to 8.5 in 2016; for the less efficiently utilised servers in traditional data centers, the estimated and predicted numbers are 1.5 in 2011 and 2 in 2016 respectively.

Cisco also predicts a 'changing of the guard' in terms of the regional distribution of cloud-based workloads: in 2011 North America led the way with 37.8 percent of 21.4m workloads, with Asia Pacific on 31.3 percent; in 2016 Asia Pacific is expected to host 36.2 percent of 112.1m workloads, with North America in second place on 26.4 percent.

What's clear is that, for the foreseeable future, organisations will be employing a mix of on-premise and outsourced IT infrastructure, with the major underlying trend being increased use of services located in public cloud data centers, particularly in the Asia Pacific region.


Topics: The 21st Century Data Center, Cloud, Data Centers


Charles has been in tech publishing since the late 1980s, starting with Reed's Practical Computing, then moving to Ziff-Davis to help launch the UK version of PC Magazine in 1992. ZDNet came looking for a Reviews Editor in 2000, and he's been here ever since.

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  • Severe Client Abuse

    That is what this article is. How many of the 7 Deadly have you Violated ?

    A miserable experience of wading through 5 pages when a single page was all that was necessary. Responsible media professionals provide their readers with a 'View as one page' option or the equivalent. This was almost as terrible as the 'Slide Show format. At minimum, you could have offered us a downloadable .pdf file.

    Please, Please, Please do not do this to us again.
    Leo Regulus
  • Too long to read :(

    I completely agree with Leo, who says " This was almost as terrible as the 'Slide Show format. At minimum, you could have offered us a downloadable .pdf file." I, and most of us, have not much time to read long written articles. Please offer either one-page article or a downloadable version as an alternative.
    • I disagree...

      I couldn't disagree more, actually. The level of detail in the read so far has been great. I'm impressed with the depth. I'm sure you'll be able to find a slimmer version of this information online somewhere else. Good luck.
  • Well written

    I am usually one to decry the evils of long articles. If I am not interested in the first 2-3 sentences I move on. But this article kept my attention and I thought it was well written. Maybe it is because I deal with data center issues on a daily basis.

    Oh well, I guess you can't please everyone.
  • I agree. Well written.

    An overview on a topic like this requires some in-depth analysis. Charles has written a clear, concise, but comprehensive overview. A one-page summary would be worthless. I do agree that a pdf would be useful for future reference. Good job.