web applications & operating cost of data center

7/31/2019 Web Applications & Operating Cost of Data Center

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International Journal in Foundations of Computer Science & Technology (IJFCST), Vol. 2, No.5, September 2012

DOI:10.5121/ijfcst.2012.2501 1

W EB A PPLICATIONS & O PERATING C OST OF D ATA C ENTER

Dr. Shrijit Joshi 1 and Meghana Joshi [email protected]@gmail.com

A BSTRACT

Traditionally, organizations use their own data centers to communicate with their users/customers throughinformation technology. Business team of the organization achieves this by funding the development of arange of web applications. Typically, web applications are developed using the components present in thedata center and using the human IT infrastructure. In other words, organization needs to incur theexpenses on data center components and human IT infrastructure for the development of new web

application. Therefore, the operating cost of the data center can change with the change in the number of web applications hosted on the organizations data center. In order to estimate the rate of increase in theoperating cost of data center with the development of new web applications, in this paper we consider thecosts required for the following seven factors human labor, data center components procurement, datacenter components maintenance, software license, software support, energy utilization, and space usage.Our proposed strategy will be useful for the business team to make a decision on whether to go ahead withthe development of web application when operating cost of data center is the primary decision makingcriteria. We also present simulation results of our proposed strategy when the business team is planning todevelop a set of web applications.

K EYWORDS

Information technology, data center, operating cost of data center, web site, web application, physicalinfrastructure, energy utilization, human IT infrastructure

1. INTRODUCTION

In todays information age, businesses use information technology (IT) to reach out to their users.IT achieves this by a very tight integration between various human and non-human ITinfrastructures, such as integration between people and software/hardware. Human ITinfrastructure includes people with technical IT skills and managerial IT skills [1]. Organizationwith better human IT infrastructure has the advantage of seamless integration between the ITdepartment and the business department of the organization. Such a seamless integration helps theorganization in developing an innovative IT product before their competitors to strengthenorganizations relationship with its users. Another resource of IT, non-human IT infrastructure, isequally important for achieving the business goal of the organization. This is because; allsoftware/hardware family of resources forms the domain of non-human IT infrastructures whichhelp in transforming innovative IT ideas of human resources from theory into physical reality.These non-human IT infrastructures are typically hosted in businesss data center facility.Therefore, availability, reliability, manageability, and agility of the data center are very criticalfor the overall functioning of the business. In other words, data center, along with human ITinfrastructure, forms the back-bone of todays IT industry.


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In this paper, we focus our attention on data center; more specifically, we discuss variouscomponents of data center, inter-relationships between those components, and estimation of operating cost of data center when transforming a newly conceived idea by human ITinfrastructure into reality. Readers are encouraged to view various studies that are carried out onhuman IT infrastructure in [2] [3] [4] [5] [6] [7].

Components of data center can be broadly categorized into: back-end data center physicalinfrastructure (BE-DCPI) components and front end data center physical infrastructure (FE-DCPI) components. In the literature [8] [9] [10] [11] [12] [13] [14], BE-DCPI components arereferenced as data center physical infrastructure. As both front-end and back-end components of the data center can be physical, the terminology mentioned in the literature is confusing.Therefore, we coin new terms to distinguish between the front-end and back-end components of the data center with a pre-fix to DCPI.

BE-DCPI components form the foundation on which hardware/software of IT reside. Examples of BE-DCPI components are land, power distribution, distribution wiring, generator, uninterruptedpower supply, batteries, transformers, humidifiers, switchgears, air conditioners, condensers,ductwork, piping, racks, computer networks, switches, gateway routers, fire alarms, smoke

detectors, & access cards. Availability, reliability, & manageability of these BE-DCPIcomponents are very critical for the functioning of the data center. For an instance; if there is anydisruption in the power supply, entire data center can go down and such a disaster can be avertedwith the help of another BE-DCPI component; more specifically by generators. Furthermore,security and fire protection components of BE-DCPI, such as fire alarm, smoke detector, accesscards, are helpful in keeping the integrity and safety of the data center. In addition to theavailability, reliability, & manageability of BE-DCPI components, agility of the components isalso important because of todays ever changing IT landscape. Agility of the components refersto the speed at which the landscape of BE-DCPI components can be adapted to the businessneeds. This characteristic of the BE-DCPI components is very essential, especially, for the timeconstrained projects.

FE-DCPI components typically are the components that utilize services offered by one or moreBE-DCPI components. Examples of FE-DCPI components are central processing units (CPU),hard disks, random access memories (RAM), application servers, webservers, database servers,proxy servers, media servers, mainframes, load balancers, domain name servers, web applicationfirewall, corporate firewall, & software such as JAVA, .NET, SAP, & ORACLE. Availability,reliability, manageability, and agility of FE-DCPI components rely on both componentsindividual characteristics and also on its dependent BE-DCPI components. For examples,hardware components of FE-DCPI such as CPU, RAM, & corporate firewall can run efficientlywhen they receive sufficient electric power (a BE-DCPI component), and can communicate withother FE-DCPI components when they are interconnected with available/reliable communicationnetworks (another BE-DCPI component). Like BE-DCPI, FE-DCPI components also need tohave very high availability, reliability, manageability, and agility for successfully running thebusiness on the Internet.

In a broader sense, the objective of the business is to increase the revenue from their IT operationand decrease the cost of IT infrastructures operation. To satisfy this business objective,researchers have formulated various methodologies for estimating the operating cost of datacenter emphasizing primarily on BE-DCPI components; please read [11] [12] [15] [13] [16] [9][17] [18] [19] [10] for more details. Now-a-days, it is well known fact that IT landscape of mostof the organizations is changing at rapid pace. As per our opinion, the reasons for the change inIT landscape from time instant t to time instant k t + where 0>k are fundamentally based onthree factors as given below. These factors are the effects of the change in business requirement


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from the business team and that causes IT teams to develop a range of new web applications [20]from time instant t to time instant k t + . These web applications are developed using the BE-DCPI components, FE-DCPI components, and human IT infrastructure. In other words,development of new web applications from time instant t to time instant k t + causes theoperating cost of data center to change.

Factor 1: Change in the number of websites organization is hosting Factor 2: Change in the number of web pages and the contents of the web pages

hosted on a website Factor 3: Architectural changes in the way web services are talking to other web

applications

Therefore, development and maintenance of new web applications change the way organizationwas operating the IT infrastructure. Referenced studies in this paper do not take into account thisvariable factor of IT infrastructure landscape while estimating the operating cost of data center. Inthis paper, we present our methodology based on the number of new web applicationsorganization is planning to develop. Our proposed methodology will aid business people to makea calculated decision on whether to give a go-ahead for developing the designed applications.

Rest of the paper is organized as follows. In Section II, we give a detailed description on how arequest flows through various BE-DCPI and FE-DCPI components when a user requests a pageon the Internet. In Section III, we describe our methodology for estimating the change in theoperating cost of a data center when business team of the organization is planning to develop newweb applications using the resources present in the data center or by brining in new resources ( on-demand ) to the data center. And in Section IV, we give our concluding remarks and futuredirections .

2. WEB APPLICATION AND DATA CENTER INFRASTRUCTURE

Users access organizations website for retrieving the desired information. Websites extract

information from the data stored at range of places in organizations data center (such as from arelational data base management system or from a network file system), processes the extracteddata to form information using some business logic, and then displays the processed informationon web pages. Furthermore, information displayed on one web page of the same or differentorganization can be fed as data to some other web page of an organization for processing. Inorder to address this complex structure of website construction, organization develops a set of web applications [21]. Figure 1 illustrates this theory. As shown in Figure 1, web pages of twoorganizations, Organization x and Organization y, are created by their respective web applications.When web page of Organization y is trying to retrieve data from the web page of Organization x orvice-versa, web applications of the concerned web pages communicate with each other.


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Figure 1 Communication between web pages through web applications.

Computer web applications (hereafter, referred as applications) are typically developed for twodistinct kinds of users users present within the organization ( internal ) and users outside of theorganization ( external ). Based on the categorization of the users, applications can also be divided

into two types internal and external applications. As the name suggests, internal applications aredesigned for internal users (such as human resources and payroll applications) and externalapplications are designed for external users (such as electronic shopping and press reports). Asthe domains of these two types of applications are distinct, we can construct following threearguments in a broader perspective:

Argument 1: Two or more internal applications can be dependent on each other;Argument 2: Two or more external applications can be dependent on each other; andArgument 3: Internal applications and external applications do not depend on each

other.

Typically for the development of efficient computer web application, organizations performfollowing integration flow chart: write an application; deploy the application on multitude of application servers [22]; integrate the application servers with multitude of webservers [23]; placeload balancers [24] to effectively balance the load on webservers; and front the load balancerswith a local domain name server (DNS) [25]. This theory is illustrated in Figure 2.


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Figure 2 Request flow through various BE-DCPI and FE-DCPI components.

As shown in Figure 2, when user requests a web page on the Internet, request flows in thefollowing manner:

Step 1: First, request is intercepted by DNS. During this step, DNS converts the URL of the webpage into an IP address. DNS then selects a load balancer using the IPaddress information and forwards the request to the selected load balancer.

Step 2: When request is flowing from DNS to load balancer, typically corporate firewallverifies the request for any intrusion detection/security risks.

Step 3: Once the security checks are passed by firewall, request flows to load balancer.Step 4: During this step, load balancer forwards the request, based on some pre-defined

load balancing algorithm, to one of the configured webservers for the web page.Step 5: Webserver then processes the static contents of the web page. For processing

dynamic contents of the web page, webserver forwards the request to one of theconfigured application servers based on some pre-defined load balancingalgorithm.

Step 6: During this step, application server processes the dynamic contents of the webpage.

Step 7: Then, application server forwards the processed contents to webserver.


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Step 8: Webserver then attaches the already processed static content to the receiveddynamic content from application server. Webserver then forwards both staticand dynamic content back to the load balancer.

Step 9: Load balancer then displays the received content as a web page to the user.

The BE-DCPI and FE-DCPI components listed above need to be procured by the organization ina data center for successfully disseminating the information in the form of web page. Asmentioned above, organizations typically have internal and external applications which can haveintrinsic inter-dependency and therefore, organization need to develop a range of applicationsusing the IT infrastructure of data center for operating the business.

Expenses incurred from the procurement and maintenance of the components present in the datacenter (data center infrastructure) constitutes a part of operating cost to business. As mentionedearlier, in a broader sense, the objective of the business is to increase the revenue from their IToperation and decrease the cost of operating the IT infrastructures. Therefore, at a fixed revenue,the lesser the expense on the data-centers operating cost; the higher will be the business profit.Consider a situation where a business wants to add/develop new web applications to enhance thefunctionalities that are currently offered by their website. In such a situation, mathematical

model(s) that gives a theoretical estimate on increase/decrease of data centers operating cost willaid business people to make a calculated decision on whether to give a go-ahead for developingthe designed applications.

In the next section, we present our solution for estimating the change in operating cost of datacenter when business is planning to develop new web applications and present an illustration todescribe our proposed solutions utility.

3. OPERATING COST OF INDIVIDUAL DATA CENTER

As mentioned in the earlier section, an organization managing their own data-center has to bearthe cost associated with procuring and maintaining the data infrastructure (BE-DCPI and FE-

DCPI components). For running the business effectively, organization needs to develop computerapplications on demand i.e., as and when the business requirement comes. In other words, when arequirement comes, organization needs to procure the necessary FE-DCPI and BE-DCPIcomponents for the application to work. Procuring the components and then configuring them asper organizations policy/applications requirement will prolong the project life cycle of theapplication development. In addition, the cost required to procure and maintain the components of the data-center will increase the absolute operating cost of the data-center.

In this paper we consider following seven factors for estimating the operating cost of a datacenter:

human labor, BE-DCPI/FE-DCPI components procurement, BE-DCPI/FE-DCPI components maintenance, software licenses, software support, energy utilization, & space usage.


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We are considering these factors for estimating the operating cost of data center because of thefollowing reasons. First , as discussed earlier, IT enables organization to reach out to the userswith the help of human IT infrastructure and non-human IT infrastructure. Therefore, the amountof expenditure organization is making on supporting human IT infrastructure (i.e., human labor)to modify/maintain the existing data center is very important for estimating the operating cost of

data center. Second , operating expense on non-human IT infrastructure rests on the number of BE-DCPI/FE-DCPI components present in the data center. As each component needs to beprocured & maintained in the organizations data center infrastructure landscape, we are takinginto account BE-DCPI/FE-DCPI components procurement & BE-DCPI/FE-DCPI componentsmaintenance as contributing factors for estimating the operating cost of data center. Third ,software license and support from software vendor are in most cases necessary to develop webapplication and to troubleshoot the web application in production and in non-productionenvironment. Therefore, we are considering software licenses & software support as contributingfactors. Additionally, to power up the components, provide chilling to the components to avoidover-heating, and to keep these components in plant, energy and space are required. Therefore,we are considering energy utilization and space usage as additional factors for estimating theoperating cost of data center.

Figure 3 Notations of factors that contribute in estimating the operating cost of data center.

The notations used for the mentioned factors are given in Figure 3. Based on these factors,operating cost of data center ( )( )t OP at time instant t can be calculated using equation 1.

( ) t t t t t t t t t t t t t t L E SS SL M P H t OP coscoscoscoscoscoscos ++++++= .(1)

Where


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t t H cos represents the human labor cost for operating the data center at time

instant t ; t

t Pcos represents the expenditure involved in procuring the data center

components (FE-DCPI and BE-DCPI components) at time instant t ; t t M cos represents the expenditure involved in maintaining the procured

components at time instant t ; t

t SLcos represents the software licensing cost paid for operating the data center attime instant t ;

t t SS cos represents the expenditure made on buying software support from the

vendor at time instant t ; t

t E cos represents the energy utilization cost for operating the data center at timeinstant t ; and

t t Lcos represents the space (land) usage co st for operating the data center at

time instant t .

{ }

{ }

{ }

{ }

{ }

{ }

{ }=

=

=

=

=

=

=

nt t t nt new

nt t t nt new

nt t t nt new

nt t t nt new

nt t t nt new

nt t t nt new

nt t t nt new

lll L

eee E

ssssssSS

slslslSL

mmm M

p p pP

hhh H

,cos2,cos1,cos,cos

,cos2,cos1,cos,cos

,cos2,cos1,cos,cos

,cos2,cos1,cos,cos

,cos2,cos1,cos,cos

,cos2,cos1,cos,cos

,cos2,cos1,cos,cos

,,,

,,,

,,,

,,,

,,,

,,,

,,,

K

K

K

K

K

K

K

..(2)

Whenever there is a demand for developing new web applications, the cost associated with eachof the seven factors mentioned above can change. Let us suppose, an organization is planning todevelop n new web applications by time instant k . Say, human labor cost, procurement cost,

maintenance cost, software license cost, software support cost, energy cost, and land usage costrequired for developing thi new web application be it h ,cos , it p ,cos , it m ,cos , it sl ,cos , it ss ,cos , it e ,cos ,

& it l ,cos , respectively. These individual costs for a set of n applications can be represented in

nt H ,cos , nt P ,cos , nt M ,cos , nt SL ,cos , nt SS ,cos , nt E ,cos , & nt L ,cos sets. Elements of these sets aregiven above in equation 2.


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Development of n new web applications can cause change in organizations expense on humanlabor. This change in human labor costs can be calculated using equation 3.

=

=+++=n

iit nt t t

k t t hhhh H

1,cos,cos2,cos1,cos

,cos L ..(3)

where k t t H ,

cos represents the change in human labor cost after developing n new web

applications.

Similarly, the change in procurement cost ( )k t t P ,cos , maintenance cost ( )k t t M ,cos , software licensecost ( )k t t SL ,cos , software support cost ( )k t t SS ,cos , energy utilization cost ( )k t t E ,cos , and spaceusage cost ( )k t t L ,cos from time instant t to time instant k can be calculated using equations 4, 5,6, 7, 8, & 9.

==+++=n

iit nt t t

k t t p p p pP

1,cos,cos2,cos1,cos

,cos L (4)

=

=+++=n

iit nt t t

k t t mmmm M

1,cos,cos2,cos1,cos

,cos L .....(5)

=

=+++=n

iit nt t t

k t t slslslslSL

1,cos,cos2,cos1,cos

,cos L .....(6)

=

=+++=n

iit nt t t

k t t ssssssssSS

1,cos,cos2,cos1,cos

,cos L ...(7)

==+++=n

iit nt t t

k t t eeee E 1

,cos,cos2,cos1,cos,

cos L ..(8)

=

=+++=n

iit nt t t

k t t llll L

1,cos,cos2,cos1,cos

,cos L .....(9)

Whenever organization is planning to develop new web applications, new FE-DCPI/BE-DCPIcomponents and/or software may be procured in the data center. Procurement of newhardware/software in the data center will extend the project development life cycle of the webapplication. Therefore, the expected business revenue from the application will be lost for thenumber of procurement delayed days. When organization is planning to develop n new webapplications by time instant k , the business loss incurred by the organization due to delay inprocurement can be calculated using equation 10.

( ) ( ) ( ) ( )=

=+++=n

iiinn

k t pd bl pd bl pd bl pd bl BL1

2211,

L (10)

Where


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k t BL , represents the business loss incurred by the organization because of thedelay in procurement of hardware/software required for developing new webapplications;

ibl represents the estimated revenue generated by the

thi new web applicationper day; and

i pd represents the number of days required for procuring the hardware/softwareto support the development of thi new web application.

Using equations 2 through 10, we can estimate the change in operating cost of datacenter ( )( )k t OP , at time instant k . This changed value can be estimated using equation 11.

( ) k t t k t t k t t k t t k t t k t t k t t k t L E SS SL M P H BLk t OP ,cos,cos,cos,cos,cos,cos,cos,, +++++++= ...(11)

From equations 1 and 11, we can estimate the operating cost of data center ( )( )k OP at timeinstant k using equation 12.

( ) ( ) ( )k t OPt OPk OP ,+= .....(12)

From equations 1, 11, & 12, we can conclude that operating cost of data center after setting n new web applications will be higher than the existing operating cost of data center if and only if the value of 0,cos >it h or 0,cos >it p or 0,cos >it m or 0,cos >it sl or 0,cos >it ss or 0,cos >it e or

0,cos >it l or 0>ibl or ( )( )0&0,cos >> iit bl p . This theory is represented mathematically inequation 13.

( ) ( )

( )>>>>>

>>

>>

>

000

0000

00

,cos,cos

,cos,cos

,cos,cos

,cos,cos

iit it

it it

it it

it it

bl pl

essslm

ph

t OPk OP ..(13)

Using equations 1, 11, 12, & 13, business team of the organization can estimate the change inoperating cost of a data center when they are planning to develop new web applications. Based onthese equations, business team can make a trade-off on whether to go ahead with the developmentof new web applications. The trade-off can be made based on how much revenue new webapplications can bring in to the organization (say, variable x ) and how much change is occurringon the operating cost of data center (say, variable y ). The higher the value of variable x and thelower the value of variable y will pose the best business case for initiating the development of new web applications.

Following illustration depicts how the theoretical equations given above can be implemented inpractice and also, depicts the alarming rate at which the operating cost of a data center canincrease with the development of new web applications to organizations website.


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Illustration 1: Consider an organization where the business team (at time instant t ) is planningto develop five new applications by time instant k . The required human labor, procurement,maintenance, software license, software support, energy, and land usage cost needed to adapt theexisting data center for developing each of these 5 new web applications are given in Figure 4.Costs given in Figure 4 for the factors - human labor, components maintenance, software support,

energy utilization, & space usage are for per year. ( Assume these new web applications do not directly generate revenue for the organization but adds the functionality to the currently provided by the organizations website. )

Figure 4 Human labor, procurement, maintenance, software license, software support, energy, andland usage cost needed to adapt the existing data center for developing new web applications.

By putting the values given in Figure 4 into equation 2, we can get the following eight sets asshown in equation 14.

{ }{ }

{ }{ }{ }{ }

{ }{ }=

=

=

=

=

=

=

=

0,0,0,0,0

700,1500,1000,800,800

9000,15000,0,0,10000

40000,70000,0,0,40000

6000,15500,5000,4000,5000

35000,100000,50000,75000,75000

15000,25000,10000,10000,150005,4,3,2,1

,cos

,cos

,cos

,cos

,cos

,cos

,cos

nt new

nt new

nt new

nt new

nt new

nt new

nt new

L

E

SS

SL

M

P

H

N

...(14)


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Using the values set in equation 14, we can estimate the change in operating cost of data centerfrom time instant t to time instant k . In order to get better insight on how much the operatingcost of a data center is increasing with the development of each of these 5 new web applications,we are estimating the change in operating cost of data center after the development of each webapplication individually. Let us say, the change in operating cost after the development of web

applications 1, 2, 3, 4, & 5 are represented by ( )k t OP ,1 , ( )k t OP ,2 , ( )k t OP ,3 , ( )k t OP ,4 ,& ( )k t OP ,5 , respectively. Estimated values of these variables are given below. (As we areassuming 0=ibl , 0

, =k t BL from equation 10.)

( )

( )

( )

( )

( ) =++++++=

=++++++=

=++++++=

=++++++=

=++++++=

700,186$,

000,227$,

600,66$,

800,89$,

800,145$,

5,cos5,cos5,cos5,cos5,cos5,cos5,cos5





t t t t t t t

t t t t t t t

t t t t t t t

t t t t t t t

t t t t t t t

lessslm phk t OP

lessslm phk t OP

lessslm phk t OP

lessslm phk t OP

lessslm phk t OP

...(15)

From the estimated values of ( )k t OP ,1 , ( )k t OP ,2 , ( )k t OP ,3 , ( )k t OP ,4 , &( )k t OP ,5 , we can see that each web application is changing the operating cost of data

center differently. Figure 5 depicts the cumulative increase in the operating cost of datacenter after the successive development of web applications 1 though 5 in succession. Inother words, value for the change in operating cost of data center in Figure 5 is calculated

using the following equation.

( )=

=n

ii AppWeb k t OPOP n

1

, ..(16)

Therefore, values shown for the Web App 1, Web App 2, Web App 3, Web App 4, &Web App 5 are calculated as follows:


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( ) ( )

( ) ( ) ( )

( )

( )

( )==

==

==

=+=+==

===

=

=

=

=

=

.300,715$,

.600,528$,

.600,301$,

.600,235$800,89$800,145$,,,

.800,145$,,

5

1

4

1

3

1

21

2

1

1

1

1

5

4

3

2

1

ii AppWeb

ii AppWeb

ii AppWeb

ii AppWeb

ii AppWeb

k t OPOP

k t OPOP

k t OPOP

k t OPk t OPk t OPOP

k t OPk t OPOP

.(17)

$-

$100,000

$200,000

$300,000

$400,000

$500,000

$600,000$700,000

$800,000

Web App 1 Web App 2 Web App 3 Web App 4 Web App 5

Figure 5 Change in operating cost of data center after the development of web applications.

From equation 15 and Figure 5, we can see that whenever new web application is developed,operating cost of the organizations data center is increasing. When organization is planning todevelop a new web application, business team of the organization can estimate the change in theoperating cost of data center using equations 12 & 15. If the estimated change is less than thetrade-off decided by the business team over the revenue from the web application, business teamcan give their consent for the development of the new web application. Such an objective criteriain decision making presents a great tool for the business team to keep the operating cost of ITdata center in check and keep the expenses on operating IT infrastructure at minimum with theincrease in the revenue from their IT operation.

The organization where there is a need of range of new applications because of their nature of work, such as in research & development firm, new web start-up, the operating cost of their datacenters can increase at an alarming rate. In order to remediate this problem, business team of theorganization should look into novel method of application hosting, such as through cloudcomputing infrastructure rather than owning a dedicated data center for their business.


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4. CONCLUSION

In this paper, we have presented a novel study that takes into account the number of webapplications organization is hosting in their data center for determining the change in operatingcost of data center. Estimation of operating cost of data center is performed by considering sevenfundamental components of the data center human labor, data center components procurement,data center components maintenance, software license, software support, energy utilization, andspace usage. The proposed strategy presents a great tool for the business team to make anobjective decision on whether to go ahead with the development of new web application. Such asobjective criteria helps the business team to keep the operating cost of data center at minimumand optimize the business revenue from their IT operation.

R EFERENCES

[1] Anandhi Bharadwaj, A resource-based perspective on information technology capability and firmperformance - an empirical investigation., MIS Quarterly , vol. 24, no. 1, pp. 159195, Mar. 2000.

[2] Terry Byrd and Douglas Turner, Measuring the flexibility of Information Technology infrastructure:

Exploratory analysis of a construct, Journal of Management Information Systems , vol. 17, no. 1, pp.167208, 2000.[3] Peter Weill, The role and value of information technology - some empirical observations., Sloan

WP No. 3433-92 , pp. 135, May 1992.[4] Curtis Armstrong and V. Sambamurthy, Information technology assimilation in firms: The infuence

of senior leadership and IT infrastructures, Information systems research , vol. 10, no. 4, pp. 304327, 1999.

[5] Erik Brynjolfsson and Lorin Hitt, Beyond computation: Information Technology, organizationaltransformation and business performance., Journal of Econmic Perspectives , vol. 14, no. 4, pp. 2348, 2000.

[6] Lawrence Loh and N. Venkatraman, Determinants of Information Technology outsourcing: A cross-sectional analysis., Journal of Management Information Systems , vol. 9, no. 1, pp. 724, 1992.

[7] Peter Weill and Michael Vitale, What IT infrastructure capabilities are needed to implement e-business models?, MIS Quarterly , vol. 1, no. 1, pp. 1734, 2002.

[8] Viswas Purani, Data center physical infrastructure for enterprise wireless LANs., Technical report, American Power Conversion (APC) , vol. WP-84 V1, pp. 1 13, 2011.

[9] Ellen Kotzbauer and Dennis Bouley, Guide for reducing data center physical infrastructure energyconsumption in federal data centers., Technical report, American Power Conversion (APC) , vol. WP250 v0, pp. 115, 2011.

[10] Suzanne Niles, Standardization and modularity in data center physical infrastructure, Technicalreport, American Power Conversion (APC) , vol. WP 116, v1, pp. 117, 2011.

[11] Neil Rasmussen, Allocating data center energy costs and carbor to IT users., Technical report, American Power Conversion (APC) , vol. WP 161, v1, pp. 118, 2010.

[12] John Karidis, Jose Moreira, and Jaime Moreno, True value: Assessing and optimizing the cost of computing at the data center level., in 6th ACM conference on Computing frontiers , New York, NY,USA, 2009, pp. 185192.

[13] Chandrakant Patel, Ratnesh Sharma, Cullen Bash, and Monem Beitelmal, Energy Flow in theInformation Technology Stack: Coefficient of performance of the ensemble and its impact on the totalcost of ownership, HP Labs, Technical report 55 , pp. 129, 2006.

[14] Chandrakant Patel and Amip Shah, Cost Model for Planning, Development and Operation of a DataCenter, HP Labs, Technical report 107 , pp. 136, 2005.

[15] Steve Greenberg, Evan Mills, and Bill Tschudi, Best Practices for Data Centers: Lessons Learnedfrom Benchmarking 22 Data Centers, CEEE Summer Study on Energy Efficiency in Buildings , pp.3/76 3/87, 2006.

[16] Justin Moore, Automated cost-aware data center management, Duke University, 2006.[17] Sophia Flucker and Robert Tozer, Minimising Data Centre Total Cost of Ownership Through Energy

Efficiency Analysis, presented at the CIBSE ASHRAE Technical Symposium, London, UK, 2012.


15/15


15

[18] Jonathan Koomey, A simple model for determining true total cost of ownership, p. 9, 2008.[19] Thomas Pisello, Simple savy savings - 9 ideas to make anyone cost cutting hero, Alinean, Inc ,

2008.[20] K. Kuppusamy and G. Aghila, MORPES: A Model for Personalized Rendering of Web Content on

Mobile Devices, International Journal in Foundations of Computer Science and Technology , vol. 2,no. 2, pp. 4352, 2012.

[21] Hans Gellersen and Martin Gaekde, Object oriented web application development., IEEE Internet Computing , pp. 6068, Jan. 1999.

[22] Mick Jordan, Laurent Daynes, Grzegorz Czajkowsk, Marcin Jarzab, and Ciarn Bryce, ScalingJ2EE TM Application Servers with the multi-tasking virtual machine., Sun Microsystems, Technical

Report , 2004.[23] Martin Arlitt and Carey Williamson, Internet web servers - Workload characterization and

performance implications., IEEE/ACM Transactions on Networking , vol. 5, no. 5, pp. 631645, Oct.1997.

[24] Marc Willebeek-LeMair and Anthony Reeves, Strategies for dynamic load balancing on highlyparallel computers., IEEE Transactions on Parallel and Distributed Systems , vol. 4, no. 9, pp. 979993, Sep. 1993.

[25] Peter Danzig, Katia Obraczka, and Anant Kumar, An analysis of wide-area name server traffic, in ACM SIGCOMM , 1992.

Authors

Dr. Shrijit Joshi has received a PhD (Computer Science) from Louisiana Tech University, USA in 2009.He has also received MS degrees in Computer Science and Mathematics from Louisiana Tech University,USA in 2007 and in 2009, respectively. He has numerous research publications in journals/conferences inthe field of biometrics, keystroke dynamics, network traffic anomaly detection, IP traceback, machinelearning, pattern recognition, hidden Markov model, artificial neural networks, & clustering; and a USAPatent on biometrics. Dr. Joshi is currently providing architectural consulting support for the ITinfrastructure design of various financial institutions.

Meghana Joshi has received a MS degree in Information Systems from Stratford University, USA in 2012.Earlier, she has received a BE degree in Electrical Engineering from VNIT, Nagpur, India in 2003. Afterthe completion of bachelors degree, she has provided consulting support to various multi-national financialand health insurance companies. Her research interests include IT infrastructure, cloud computing, virtualmachines, computer graphics, pattern recognition, and machine learning.

web applications & operating cost of data center

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