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PART IFOUNDATIONSCOPYRIGHTED MATERIAL

high yield (i.e., profit per unit of resource) user jobs, leading to a scenario whereshared systems are viewed as a marketplace, wher e users compete f

management of workload in a virtualized system, namely isolation, consolida-tion, and migration [23].Workload isolation is achieved since all program

features, thus making KVM simpler and smaller than hypervisors that takecontrol of the entire machine [28].KVM lever ages hardware-assisted virtualiza

1.2.7 Autonomic ComputingThe increasing complexity of computing systems has motivated research onautonomic computing, which seeks to improve systems b

enables on-demand provisioning of servers running several choices of operatingsystems and a customized software stack. Infrastructure services are con

include an in-memory object cache (memcache), mail service, instant messagingservice (XMPP), an image manipul ation service, and integration with Goog

Armbrust et al. [5] propose definitions for public cloud as a “cloud madeavailable in a pay-as-you-go manner to the general public” and priva te cloud

quantity at any time. In particular, it is expected that the additional resourcescan be (a) provisioned, possibly automatically, when an application l

Virtually all VIMs we investigated present a set of basic features related tomanaging the life cycle of VMs, including networking groups of VMs togeth

NFS; a storage controller provides the layer of abstraction between virtual andphysical storage [48].In the VI management sphere, storage virtualizati

Virtual Clusters. Several VI managers can holistically manage groups ofVMs. This feature is useful for provisioning computing virtual clusters ondeman

1.5.2 Case StudiesIn this section, we describe the main features of the most popular VI managersavailable. Only the most prominent and dist inguishing

TABLE 1.1. Feature Comparison of Virtual Infrastructure ManagersLicenseInstallationPlatform ofControllerClient UI,API, LanguageBindingsBackendHypervis

Citrix Essentials. The Citrix Essentials suite is one the most feature completeVI management software available, focusing on management and automation

providing a Globus Web Services Resource Framework (WSRF) interface. Italso provides a backend service, named Pilot, which spawns VMs on clustersmanag

including support for managing physical server pools, storage pools, useraccounts, and VMs. All features are accessible through a Web interface [67].T

interfaces with vCenter Server. In this configuration, vSphere can be used byservice providers to build public clouds. In terms of interfacing with pub

GUIs are preferred by end users who need to launch, customize, andmonitor a few virtual servers and do not necessary need to repeat the processseveral

Hypervisor and Operating System Choice. Traditionally, IaaS offeringshave been based on heavily customized open-source Xen deployments. IaaSproviders

TABLE 1.2. Feature Comparison Public Cloud Offerings (Infrastructure as a Service)GeographicPresenceClient UIAPI LanguageBindingsPrimaryAccess toServe

CHAPTER 1INTRODUCTION TO CLOUDCOMPUTINGWILLIAM VOORSLUYS, JAMES BROBERG, and RAJKUMAR BUYYA1.1 CLOUD COMPUTING IN A NUTSHELLWhen plugging an electric

Flexiscale. Flexiscale is a UK-based provider offering services similar innature to Amazon Web Services. However, its virtual servers offer somedistin

Rackspace Cl oud Servers. Rackspace Cloud Servers is an IaaS solutionthat pr ovides fixed size instances in the cloud. Cloud Servers offers a range ofL

Traditionally, Web and enterprise application developers have chosen rela-tional databases as the preferred persistence method. These databases offer

TABLE 1.3. Feature Comparison of Platform-as-a-Service Cloud OfferingsTarget UseProgrammingLanguage,FrameworksDeveloperToolsProgrammingModelsPersisten

application developer using a limited subset of the native APIs on eachplatform, and in some instances you need to use specific Google APIs suchas URLF

security, data lock-in, availability of service, disaster recovery, performance,scalability, energy-efficiency, and programmability.1.8.1 Security, Pri

1.8.3 Availability, Fault-Tolerance, and Disaster RecoveryIt is expected that users will have certain expectations about the service level tobe provid

year. Besides the monetary cost, data centers significantly impact the environ-ment in terms of CO2emissions from the cooling systems [52].In addition

5. M. Armbrust, A. Fox, R. Griffith, A. D. Joseph, and R. Katz, Above the Clouds:A Berkeley View of Cloud Computing, UC Berkeley Reliable Adaptive Dist

22. R. Uhlig et al., Intel virtualization technology, IEEE Computer, 38(5):4856, 2005.23. P. Barham et al., Xen and the art of virtualization, in Pro

Many practitioners in the commercial and academic spheres have attemptedto define exactly what “cloud computing” is and what unique characteristics itp

45. M. D. de Assuncao, A. di Costanzo, and R. Buyya, Evaluating the costbenefit ofusing cloud computing to extend the capacity of clusters, in Proceed

64. Citrix Systems Inc., Citrix essentials for Hyper-V, http://www.citrix.com/ehv,22/4/2010.65. Distributed Systems Architecture Group, OpenNebula: Th

Internet [8]. In midst of such hype, a great deal of confusion arises when tryingto define what cloud computing is and which computing infrastructures

This model brings benefits to both consumers and providers of IT services.Consumers can attain reduction on IT-related costs by choosing to obtaincheap

between software stacks and operating systems [11]. In addition, the unavail-ability of efficient computer networks meant that IT infrastructure should

intent of serving end-user applications, their true power resides in its interfacebeing accessible by other services. An enterprise application that f

Globus Toolkit [18] is a middleware that implements several standard Gridservices and over the years has aided the deployment of several service-orien