Editing Data center (section)

===Design criteria and trade-offs===
* '''Availability expectations''': The costs of avoiding downtime should not exceed the cost of the downtime itself<ref>Clark, Jeffrey. "The Price of Data Center Availability—How much availability do you need?", Oct. 12, 2011, The Data Center Journal {{cite web|url=http://www.datacenterjournal.com/home/news/languages/item/2792-the-price-of-data-center-availability|title=Data Center Outsourcing in India projected to grow according to Gartner |access-date=2012-02-08|url-status=dead|archive-url=https://web.archive.org/web/20111203145721/http://www.datacenterjournal.com/home/news/languages/item/2792-the-price-of-data-center-availability|archive-date=2011-12-03 }}</ref>
* '''Site selection''': Location factors include proximity to power grids, telecommunications infrastructure, networking services, transportation lines and emergency services. Other considerations should include flight paths, neighboring power drains, geological risks, and climate (associated with cooling costs).<ref>{{cite web|url=http://searchcio.techtarget.com/news/1312614/Five-tips-on-selecting-a-data-center-location|title=Five tips on selecting a data center location}}</ref>
** Often, power availability is the hardest to change.

====High availability====
{{Main|High availability}}
Various metrics exist for measuring the data-availability that results from data-center availability beyond 95% uptime, with the top of the scale counting how many ''nines'' can be placed after ''99%''.<ref>{{Cite web|url=https://www.youtube.com/watch?v=DPcM5UePTY0| archive-url=https://web.archive.org/web/20120829083144/http://www.youtube.com/watch?v=DPcM5UePTY0&gl=US&hl=en| archive-date=2012-08-29 | url-status=dead|title=IBM zEnterprise EC12 Business Value Video| website=[[YouTube]] }}</ref>

====Modularity and flexibility====
{{main|Modular data center}}
Modularity and flexibility are key elements in allowing for a data center to grow and change over time. Data center modules are pre-engineered, standardized building blocks that can be easily configured and moved as needed.<ref>Niles, Susan. "Standardization and Modularity in Data Center Physical Infrastructure," 2011, Schneider Electric, page 4. {{cite web|url=http://www.apcmedia.com/salestools/VAVR-626VPD_R1_EN.pdf|title=Standardization and Modularity in Data Center Physical Infrastructure |access-date=2012-02-08|url-status=dead|archive-url=https://web.archive.org/web/20120416120624/http://www.apcmedia.com/salestools/VAVR-626VPD_R1_EN.pdf|archive-date=2012-04-16 }}</ref>

A modular data center may consist of data center equipment contained within shipping containers or similar portable containers.<ref>{{cite web|url=http://www.datacenterknowledge.com/archives/2011/09/08/strategies-for-the-containerized-data-center/|title=Strategies for the Containerized Data Center|date=September 8, 2011}}</ref> Components of the data center can be prefabricated and standardized which facilitates moving if needed.<ref>{{cite web|url=http://www.infoworld.com/d/green-it/hp-says-prefab-data-center-cuts-costs-in-half-837?page=0,0|title=HP says prefab data center cuts costs in half|first=James|last=Niccolai|date=2010-07-27}}</ref>