Within the Cloud: Technical Concepts of Cloud Computing - Deploying and Managing a Cloud Infrastructure - page 55

has evolved into what we now know as the cloud data center. Then we shall look at a few
software platforms that go hand in hand with the hardware to provide us with what we
truly know as cloud computing.
Defining a Data Center
A data center, in the strictest sense, is simply a facility used to house technological equip-
ment, usually computer systems and their components. This usually takes the form of
computing and storage units as well as telecommunications equipment. Each data center
is a little different based on the type of application it is used for. Large data centers cost
upward of $100 million to build in the first place and somewhere between $10 million and
$30 million to operate yearly.
There are many ways to quantify total cost of ownership (TCO) for data centers:
Per Kilowatt Data centers are power hogs. And since they guzzle up electricity like a
water tank with a hole, some would calculate TCO per kilowatt of power required.
Per Square Area Another method for calculating TCO is the amount of area the data cen-
ter occupies. This has something to do with the amount of cooling that data centers require
because of the large heat output being generated by power-hungry equipment. It takes into
consideration the amount of electricity consumed, the amount of cooling required, and the
manpower to manage the entire area of the data center. This is expressed as cost per square
foot or meter, depending on which measurement standard the organization follows.
Per Rack Out of all the ways to compute for TCO, this one makes more sense to both IT
professionals and facilities personnel because it is easier to quantify since parameters such
as power, cooling, and displacement (required area) are pretty much standardized across
open-frame racks or enclosures or cabinets as well as the IT equipment that goes in them.
Therefore, it is more reasonable to use this method of physical quantification because all
the quantifiable elements of all the rack components simply have to be added to get the cost
per rack.
The “per rack” notation is the most common way of referring to different
aspects of the data center, such as heat generation, power consumption,
computing power, and cost.
But of the total cost of ownership of a data center, approximately 50 percent goes to
disaster prevention and recovery plans and their execution as well as hardware and soft-
ware maintenance, which includes uninterruptible power supply and networking. The rest
is spent on temperature control, utility bills, and various taxes and labor costs. In fact,
approximately 40 percent of the overall TCO is spent on labor cost alone; data centers
need 24-hour, round-the-clock monitoring to ensure 100 percent uptime and error control.
When talking about TCO per rack, approximately half of its lifetime cost goes to capital
expense, and the other half goes to operational expense, which is shown in Figure 3.1.