On March 15, 2007, wiki entered the Oxford English Dictionary Online. Still, why would anyone use a dictionary to find out about wikis? We learned that Oxford had accepted the word from the Wikipedia entry for Wiki.

We also learned, “A wiki is a collaborative website which can be directly edited by anyone with access to it. Ward Cunningham, developer of the first wiki, WikiWikiWeb, originally described it as ‘the simplest online database that could possibly work.’ One of the best-known wikis is Wikipedia.”

We also learned that Ward Cunningham, the developer of the WikiWikiWeb, was thinking of a shuttle bus at the Honolulu airport when he named the site, which he modeled, in part, on Apple’s HyperCard. Well, you get the picture. If you want to know more about almost anything, visit its wiki.

Why doesn’t the industry served by Mission Critical have its own wiki? The industry’s servers, after all, host many of the most prominent. Well, Mission Critical aims to find out. We’re taking a decidedly low-tech approach to starting wiki-Mission Critical. Please read our first contributions below and feel free to email us (heslink@bnpmedia.com) your own contribution. And when we have a critical mass, we’ll launch. 

Coefficient of Efficiency: The Coefficient of Efficiency is a measure of energy efficiency for a data center. COE = Average Utility Input kW/Average_ UPS Output kW. COE is customarily calculated for the warmest month of the year and for a year. (Cyrus Izzo)

Isolated cooling air: Isolated cooling air means chilled air delivered to servers without previously mixing with warmer data center air. It provides for much improved control over server inlet air temperatures which, in turn, allows_an operator to increase supply air temperatures to about 70 deg F, and take advantage of substantially_more hours of “free cooling” through air side or water side economizers. This is one of the most promising energy-efficiency measures available to new and legacy data centers today. (Bruce Myatt)

Concurrent Maintainability: A data center is concurrently maintainable if any critical system or component within a critical system can be removed from service at any time without significantly increasing the risk of a computer load outage. An example is two redundant UPS systems that are arranged so that one UPS system can supply the downstream distribution systems of both while the other UPS is removed from service and returned to service. (Christopher Johnston)

Computer Outage: An often-mentioned but seldom- defined term that describes what a data center is intended to avoid. To some people, computer outage means a reduction of power or cooling significant enough to cause an outage of all computer load. To others it can be the loss of a portion of the computer load or even a single computer. Precise definition of this term and consensus among stakeholders should be a goal of every data center team. (Christopher Johnston)