Cloud & Computing

1. WHAT IS CLOUD & COMPUTING? 1.1

What is cloud?

A cloud is a pool of virtualized computer resources. A cloud can: •

Host a variety of different workloads, including batch-style back-end jobs and interactive, User- facing applications.

•

Allow workloads to be deployed and scaled-out quickly through the rapid provisioning of

•

virtual machines or physical machines

•

Support redundant, self-recovering, highly scalable programming models that allow

•

workloads to recover from many unavoidable hardware/software failures

•

Monitor resource use in real time to enable rebalancing of allocations when needed

Clouds also support non grid environments, such as a three-tier Web architecture running Standard or Web 2.0 applications. A cloud is more than a collection of computer resources because a cloud provides a mechanism to manage those resources. Management includes provisioning, change requests, reimaging, workload rebalancing, deprovisioning, and monitoring. A cloud infrastructure can be a cost efficient model for delivering information services, reducing IT management complexity, promoting innovation, and increasing responsiveness through real time workload balancing. The Cloud makes it possible. The term cloud is used as a metaphor for the Internet, based on how the Internet is depicted in computer network diagrams and is an abstraction for the complex infrastructure it conceals.

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Figure 1.1 – The cloud A cloud is a type of parallel and distributed system consisting of a collection of interconnected and virtualized computers that are dynamically provisioned and presented as one or more unified computing resources based on service-level agreements established through negotiation between the service provider and consumers. At a cursory glance, Clouds appear to be a combination of clusters and Grids. However, this is not the case. Clouds are clearly next-generation data centers with nodes “virtualized” through hypervisor technologies such as VMs, dynamically “provisioned” on demand as a personalized resource collection to meet a specific service-level agreement, which is established through a “negotiation” and accessible as a compostable service via “Web 2.0” technologies.

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1.2

What is computing?

Computing is usually defined as the activity of using and developing computer technology, computer hardware, and software. It is the computer-specific part of information technology. Computer science (or computing science) is the study and the science of the theoretical foundations of information and computation and their implementation and application in computer systems. “In a general way, we can define computing to mean any goal-oriented activity requiring, benefiting from, or creating computers. Thus, computing includes designing and building hardware and software systems for a wide range of purposes; processing, structuring, and managing various kinds of information; doing scientific studies using computers; making computer systems behave intelligently; creating and using communications and entertainment media; finding and gathering information relevant to any particular purpose, and so on. The list is virtually endless, and the possibilities are vast.”

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2.THE CLOUD COMPUTING – AN INTRODUCTION 2.1

Definition Cloud Computing, which refers to the concept of dynamically provisioning

processing time and storage space from a ubiquitous “cloud” of computational resources, allows users to acquire and release the resources on demand and provide access to data from processing elements, while relegating the physical location and exact parameters of the resources. As the user could see, Cloud Computing means scalability on demand, flexibility to meet business changes and easy to use and manage. According to Wikipedia, Cloud computing is a style of computing in which dynamically scalable and often virtualized resources are provided service over the Internet. Users need not have knowledge of, expertise in, or control over the technology infrastructure in the "cloud" that supports them.

Figure 2.1 – Defining cloud computing 2.2

Cloud computing technology and cloud services Cloud computing technology refers to the technology (including infrastructure, platforms,

and applications) that enable the IT functionality to be exposed as services in a multitenant manner. The enabling technologies include (but not limited to) virtualization, grid technologies, SaaS enabled application platform (SEAP), Service Oriented Architecture (SOA), Metering tools and technologies etc. Cloud ‘services’ refer to those types of services that are exposed by a cloud

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vendor and that can be used by a cloud consumer on a ‘pay per use’ basis. These services are exposed as industry standard interfaces like web services (using service oriented architecture, SOA [4]) or any proprietary (though rarely) services.

2.3

The promises of cloud computing Cloud computing seems to offer some incredible benefits for communicators: the availability

of an incredible array of software applications, access to lightning-quick processing power, unlimited storage, and the ability to easily share and process information. All of this is available through your browser any time you can access the Internet. While this might all appear enticing, there remain issues of reliability, portability, privacy, and security.

Figure 2.2 - Web-based operating systems, eyeOS

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3. EVOLUTION OF CLOUD COMPUTING

Cloud computing is an important topic. However it is not a revolutionary new development. Rather it is an evolution that has taken place over several decades, as shown in Figure-

Figure 3.1 - Evolution towards cloud computing The trend toward cloud computing started in the late 1980s with the concepts of grid computing when, for the first time, a large number of systems were applied to a single problem, usually scientific. Many people ask us what the difference is between grid and cloud computing. The primary difference is how each provides the needed resources to a workload. • In grid computing, the focus is on the ability of moving a workload to the

location of the needed computing resources, which are mostly remote and are readily available for use. Usually a grid is a cluster of servers on which a large task could be divided into smaller tasks to run in parallel. From this point of view, a grid could actually be viewed as just one virtual server. Grids also require applications to conform to the grid software interfaces.

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• In a cloud environment, computing resources, such as servers, can be

dynamically shaped or carved out from its underlying hardware infrastructure and made available to a workload. In addition, while a cloud does support grid, a cloud can also support nongrid environments, such as a three-tier Web architecture running traditional or Web 2.0 applications. In the 1990s the concept of virtualization was expanded beyond virtual servers to higher levels of abstraction, first the virtual platform, and second the virtual application. Utility computing offered clusters as virtual platforms for computing with a metered business model. More recently software as a service (SaaS) raised the level of virtualization to the application, with a business model of charging not by the resources consumed, but by the value of the application to subscribers. The concept of cloud computing has evolved from the concepts of grid, utility, and SaaS. It is an emerging model where users can gain access to their applications from anywhere through their connected devices. These applications reside in massively-scalable data centers where compute resources can be dynamically provisioned and shared to achieve significant economies of scale. The proliferation of smart mobile devices, high speed wireless connectivity, and rich browser based Web 2.0 interfaces has made the network-based cloud computing model not only practical but also a source of reduced IT complexity.

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Figure 3.2 - Computing paradigm shift. (Over six distinct phases, computers have evolved from dummy terminals to grids and clouds)

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4 . CLOUD SERVICES OFFERINGS

4.1 Software as a Service (SaaS) a. Software as a service features a complete application offered as a service on

demand. A single instance of the software runs on the cloud and services multiple end users or client organizations. b. The most widely known example of SaaS is salesforce.com, though many

other examples have come to market, including the Google Apps offering of basic business services including email and word processing.

4.2 Platform as a Service (PaaS) a. Platform as a service encapsulates a layer of software and provides it as a

service that can be used to build higher-level services. There are at least two perspectives on PaaS depending on the perspective of the producer or consumer of the services: i.

Someone producing PaaS

ii.

Someone using PaaS

b. Commercial examples of PaaS include the Google Apps Engine, which serves applications on Google’s infrastructure. PaaS services such as these can provide a powerful basis on which to deploy applications, however they may be constrained by the capabilities that the cloud provider chooses to deliver.

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Figure 4.1 – Services at a Glance 4.3 Infrastructure as a Service (IaaS) a. Infrastructure as a service delivers basic storage and compute capabilities as

standardized services over the network. Servers, storage systems, switches, routers, and other systems are pooled and made available to handle workloads that range from application components to high-performance computing applications. b. Commercial examples of IaaS include Joyent, whose main product is a line of virtualized servers that provide a highly available on-demand infrastructure.

Figure 4.2 - Cloud computing means using IT infrastructure as a service

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Figure 4.3 – Cloud computing service providers

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5. WHAT IS INSIDE THE CLOUD – AN ARCHITECTURE MAP Cloud computing is emerging as a model in support of “everything-as-a-service” (XaaS) virtualized physical resources, virtualized infrastructure, as well as virtualized middleware platforms and business applications are being provided and consumed as services in the Cloud. How do we compare and understand these Cloud technologies and services from a technology, software architectural, and from a business perspective? As a first step towards answering these questions, we propose a generic Cloud computing stack that classifies Cloud technologies and services into different layers. We explain each layer through examples and demonstrate how this model helps in explaining the overall Cloud computing landscape. In the spirit of earlier distributed computing architectures we therefore propose a first architectural categorization of Cloud technologies as a stack of service types. Our stack was inspired by the “everything as a service” (XaaS) taxonomy; Infrastructure as a Service (IaaS), Platform as a Service (PaaS), and Software as a Service (SaaS).

Figure 5.1 - Current cloud computing model

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5.1 Infrastructure as a Service On the lowest level of the infrastructure closest to the hardware we distinguish two types of services, Physical Resource Set (PRS) and Virtual Resource Set (VRS) services. Both of these service types provide a management front-end application for a set or pool of resources in order to allow higher level services to automate setup and tear-down, demand based scalability, fail-over, and operating system hosting. Primary functionality includes starting and stopping individual resources, OS imaging, and network topology setup and capacity configuration.

5.2 Platform as a Service Moving up to the PaaS level of our integrated stack we categorize the services into Programming Environments and Execution Environments. Example of the former is Sun’s project Caroline and the Django framework, and examples of the latter are Google’s App Engine, Joyent’s Reasonably Smart and Microsoft’s Azure. As seen by these examples an Execution Environment PaaS typically also encompasses a Programming Environment PaaS. From a platform point of view, an operating system provides a set of basic interfaces for applications to use. By far the most well-known example of an operating system in the cloud today is Amazon’s Elastic Compute Cloud (EC2). EC2 provides customer-specific Linux instances running in virtual machines (VMs). From a technical perspective, it might be more accurate to think of EC2 as a platform for VMs rather than operating systems.

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Figure 5.2 – Cloud stack

5.3 Software as a Service All the applications that run on the Cloud and provide a direct service to the customer are located in the SaaS layer. The application developers can either use the PaaS layer to develop and run their applications or directly use the IaaS infrastructure. Here we distinguish between Basic Application Services and Composite Application Services. Examples of Basic Application Services are the OpenId, Amazon’s EC2 and Google Maps services.

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6 . SEVEN STANDARDS OF CLOUD COMPUTING SERVICES

6.1 World-class security – Provision world-class security at every level. a. Physical security b. Network security c. Application security d. Secure data-backup strategy

6.2 Trust and transparency – Provide transparent, real-time, accurate service performance and availability information.

6.3 True Multitenancy – Deliver maximum scalability and performance to customers with a true multitenant architecture. Multitenancy is: a. The platform for high performance b. The platform for high availability

6.4 Proven scale – Support millions of users with proven scalability. a.

Proof of the ability to scale to hundreds of thousands of subscribers

b.

Resources to guarantee the highest standards of service quality, performance, and security to every customer

c.

Support that responds quickly and accurately to every customer

6.5 High performance – Cloud-computing platforms must deliver consistent, high-speed systems performance worldwide and provide detailed historical statistics to back up performance claims, including: a.

Average page response times

b.

Average number of transactions per day.

6.6 Complete disaster recovery – Protect customer data by running the service on multiple, geographically dispersed data centers with extensive backup, data archive, and failover capabilities.

6.7 High availability – Equip world-class facilities with proven high-availability infrastructure and application software.

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7. HOW DOES IT WORK? - OPERATING PRINCIPLE Basically there are three stages for working in cloud –

Stage 1:

At this stage from a client computer a request is sent to a control node through internet regarding the permission to use the cloud infrastructure.

Stage 2:

In the second stage the control node processes our request, and according to our need allot the space in the storage database, requested applications from application servers, and the platform i.e. operating system.

Stage 3:

When the requested commodities are fulfilled we can access any computer, any database for our computing purpose. If we want to save any data then we can store it in the allotted cloud storage database server.

Figure 7.1 – How cloud computing works

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8. TYPES OF CLOUD All of the architectural and organizational considerations mentioned thus far generally apply to all implementations of a cloud infrastructure. As we focus on building the cloud, a number of models have been developed for (deploying?) a cloud infrastructure:

8.1

Public Cloud:

In simple terms, public cloud services are characterized as being available to clients from a third party service provider via the Internet. The term “public” does not always mean free, even though it can be free or fairly inexpensive to use. A public cloud does not mean that a user’s data is publically visible; public cloud vendors typically provide an access control mechanism for their users. Public clouds provide an elastic, cost effective means to deploy solutions.

Figure 8.1 - Public Cloud 8.2

Private Cloud:

A private cloud offers many of the benefits of a public cloud computing environment, such as being elastic and service based. The difference between a private cloud and a public cloud is that in a private cloud-based service, data and processes are managed within the organization without the restrictions of network bandwidth, security exposures

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and legal requirements that using public cloud services might entail. In addition, private cloud services offer the provider and the user greater control of the cloud infrastructure, improving security and resiliency because user access and the networks used are restricted and designated.

Figure 8.2 – Private Cloud 8.3

Community Cloud:

A community cloud is controlled and used by a group of organizations that have shared interests, such as specific security requirements or a common mission. The members of the community share access to the data and applications in the cloud.

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Figure 8.3 – Community cloud 8.4

Hybrid Cloud: A hybrid cloud is a combination of a public and private cloud that interoperates. In

this model users typically outsource non-business-critical information and processing to the public cloud, while keeping business-critical services and data in their control.

Figure 8.4 – Hybrid Cloud

9 .KEY CHARACTERISTICS OF CLOUD COMPUTING 20

9.1

Agility Agility improves with users able to rapidly and inexpensively re-provision

technological infrastructure resources. The cost of overall computing is unchanged, however, and the providers will merely absorb up-front costs and spread costs over a longer period.

9.2

Cost Cost is claimed to be greatly reduced and capital expenditure is converted to

operational expenditure. This ostensibly lowers barriers to entry, as infrastructure is typically provided by a third-party and does not need to be purchased for one-time or infrequent intensive computing tasks. Pricing on a utility computing basis is fine-grained with usage-based options and fewer IT skills are required for implementation (in-house). Some would argue that given the low cost of computing resources, that the IT burden merely shifts the cost from in-house to outsourced providers. Furthermore, any cost reduction benefit must be weighed against a corresponding loss of control, access, and security risks.

9.3

Device and location independence Device and location independence enable users to access systems using a web

browser regardless of their location or what device they are using (e.g., PC, mobile). As infrastructure is off-site (typically provided by a third-party) and accessed via the Internet, users can connect from anywhere.

9.4

Multi-tenancy Multi-tenancy enables sharing of resources and costs across a large pool of users

thus allowing for: •

Centralization of infrastructure in locations with lower costs (such as real estate, electricity, etc.)

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Peak-load capacity increases (users need not engineer for highest possible loadlevels)

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Utilization and efficiency improvements for systems that are often only 10–20% utilized.

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9.5

Reliability Reliability improves through the use of multiple redundant sites, which makes

cloud computing suitable for business continuity and disaster recovery. Nonetheless, many major cloud computing services have suffered outages, and IT and business managers can at times do little when they are affected.

9.6

Scalability Scalability via dynamic ("on-demand") provisioning of resources on a fine-

grained, self-service basis near real-time, without users having to engineer for peak loads. Performance is monitored and consistent and loosely-coupled architectures are constructed using web services as the system interface.

9.7

Security Security typically improves due to centralization of data, increased security-

focused resources, etc. Providers typically log accesses, but accessing the audit logs themselves can be difficult or impossible. Ownership, control, and access to data controlled by "cloud" providers may be made more difficult, just as it is sometimes difficult to gain access to "live" support with current utilities.. Currently, many developers are implementing OAuth (open protocol for secure API authorization), as it allows more granularity of data controls across cloud applications.

9.8

Sustainability Sustainability comes about through improved resource utilization, more efficient

systems, and carbon neutrality. Nonetheless, computers and associated infrastructure are major consumers of energy. A given (server-based) computing task will use some amount of energy whether it is on-site, or off.[

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10. VIRTUALIZATION IN CLOUD COMPUTING 10.1 Virtualization Virtualization refers to the abstraction of logical resources away from their underlying physical resources in order to improve agility and flexibility, reduce costs and thus enhance business value. In a virtualized environment, computing environments can be dynamically created, expanded, shrunk, or moved as demand varies. Virtualization is therefore extremely well suited to a dynamic cloud infrastructure, because it provides important advantages in sharing, manageability, and isolation (that is, multiple users and applications can share physical resources without affecting one another). Virtualization allows a set of underutilized physical servers to be consolidated into a smaller number of more fully utilized physical servers, contributing to significant cost savings.

Figure 10.1 – Virtualization of cloud infrastructure

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10.2 Automation Infrastructure administration is one of the major challenges in a virtualization environment. Simply building a virtualization environment without the proper approach to administration can increase complexity and thus generate added costs—costs high enough to cancel out the cost savings derived from virtualization in the first place. Automation is the key to managing these problems. It is critical that a cloud be equipped with tools that facilitate, simplify, and enable management of the physical environment that provides the virtual server resources.

10.3 How does server virtualization work? In most cases, server virtualization is accomplished by the use of a hypervisor to logically assign and separate physical resources. The hypervisor allows a guest operating system, running on the virtual machine, to function as if it were solely in control of the hardware, unaware that other guests are sharing it. Each guest operating system is protected from the others and is thus unaffected by any instability or configuration issues of the others. Today, hypervisors are becoming a ubiquitous virtualization layer on client and server systems. There are two major types of hypervisors: bare-metal and hosted hypervisors.

10.4 Types of virtualization 10.4.1

Platform virtualization which separates an operating system from the underlying platform resources.

10.4.2

Full Virtualization is a virtualization technique used to provide a certain kind of virtual machine environment, namely, one that is a complete simulation of the underlying hardware. In such an environment, any software capable of execution on the raw hardware can be run in the virtual machine and, in particular, any operating systems. Other forms of platform virtualization allow only certain or modified software to run within a virtual machine. Full virtualization is only possible given the right combination of hardware and software elements. •

A key challenge for full virtualization is effect of every operation performed within a given virtual machine must be kept within that virtual machine – virtual

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operations cannot be allowed to alter the state of any other virtual machine, the control program, or the hardware. •

Full virtualization has proven highly successful for •

sharing a computer system among multiple users,

•

isolating users from each other (and from the control program) and

•

emulating new hardware to achieve improved reliability, security and productivity

10.4.3 Para virtualization, a virtualization technique that presents a software interface to

virtual machines that is similar, but not identical, to that of the underlying hardware, thereby requiring guest operating systems to be adapted. This method uses a hypervisor for shared access to the underlying hardware but integrates virtualization-aware code into the operating system itself. This approach obviates the need for any recompilation or trapping because the operating systems themselves cooperate in the virtualization process 10.4.4 Operating system-level virtualization, a method where the operating system

allows for multiple user-space instances (virtual hosting, chroot jail + resource management). 10.4.5 Application virtualization, the hosting of individual applications on alien

hardware/software Portable application, a computer software program that runs from a removable storage device as a USB flash drive. 10.4.6 Software virtualization allows underutilized servers to become fully utilized,

saving the company significant costs in hardware and maintenance. A Xen virtualization model provides significant benefits:

10.5 Storage architecture in the cloud Computing without data is as rare as data without computing. The combination of data and computer power is important. Computer power often is measured in the cycle speed of a processor. Computer speed also needs to account for the number of processors. When looking at disk storage, the amount of space is often the primary measure. The number of

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gigabytes or terabytes of data needed is important. But access rates are often more important.

Figure 10.2 – Green Cloud Architecture Being able to only read sixty megabytes per second may limit your processing capabilities below your computer capabilities. Individual disks have limits on the rate at which they can process data. A single computer may have multiple disks. So data placement can be an important factor in achieving high data access rates. Spreading the data over multiple computer nodes may be desired, or having all the data reside on a single node may be required for optimal performance.

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Figure 10.3 - Secure virtual computing Typically a single machine has both computer power and disks. The ratio of disk capability to computer capability is fairly static. With the Google file system, the single node’s computer power can be used against very large data by accessing the data through the network and staging it on the local disk. Alternatively, if the problem lends itself to distribution, then many computer nodes can be used allowing their disks to also be involved.

10.6 Desktop virtualization (Virtual Desktop) 27

Desktop virtualization (or Virtual Desktop Infrastructure) is a server-centric computing model that borrows from the traditional thin-client model but is designed to give system administrators and end-users the best of both worlds: the ability to host and centrally manage desktop virtual machines in the data center while giving end users a full PC desktop experience. The user experience is intended to be identical to that of a standard PC, but from a thin client device or similar, from the same office or remotely.

Figure 10.4 - Delivery of virtual desktop 10.6.1

Advantages a.

Instant provisioning of new desktops.

b.

Near-zero downtime in the event of hardware failures.

c.

Significant reduction in the cost of new application deployment.

d.

Robust desktop image management capabilities.

e.Existing desktop-like performance including multiple monitors, bi-directional audio/video, streaming video, USB support etc. f. Desktop computing power on demand

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Figure 10.5 – Comparison of Traditional & Virtual Desktop Computing

10.7 Virtual Network Computing In computing, Virtual Network Computing (VNC) is a graphical desktop sharing system that uses the RFB protocol to remotely control another computer. It transmits the keyboard and mouse events from one computer to another, relaying the graphical screen updates back in the other direction, over a network. VNC is platform-independent – a VNC viewer on one operating system may connect to a VNC server on the same or any other operating system. There are clients and servers for many GUI-based operating systems and for Java. Multiple clients may connect to a VNC server at the same time.

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11. APPLICATIONS

There will be to many applications of cloud computing, but its most important use is in IT industry. The other fields where the cloud computing may be used are as follows:

•

Aerospace

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Defense

•

Telecommunications

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Energy

•

Healthcare

•

Financial services

•

Government

•

Non‐profit

•

Media

•

Manufacturing

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Figure 11.1 - Global Cloud exchange and market infrastructure for trading services

12. CLOUD COMPUTING BENEFITS In order to benefit the most from cloud computing, developers must be able to refractor their applications so that they can best use the architectural and deployment paradigms that cloud computing supports. The benefits of deploying applications using cloud computing include reducing run time and response time, minimizing the risk of deploying physical infrastructure, lowering the cost of entry, and increasing the pace of innovation.

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Figure 12.1 – Cloud Computing Benefits 12.1 Reduce run time and response time For applications that use the cloud essentially for running batch jobs, cloud computing makes it straightforward to use 1000 servers to accomplish a task in 1/1000 the time that a single server would require.

12.2 Minimize infrastructure risk IT organizations can use the cloud to reduce the risk inherent in purchasing physical servers. The way in which cloud computing minimizes infrastructure risk is by enabling surge computing, where an enterprise datacenter (perhaps one that implements a private cloud) augments its ability to handle workload resources can be better matched to immediate needs, and at lower cost.

12.3 Lower cost of entry There are a number of attributes of cloud computing that help to reduce the cost to enter new markets:

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a.

Because infrastructure is rented, not purchased, the cost is controlled, and the capital investment can be zero.

b.

Applications are developed more by assembly than programming. This rapid application development is the norm, helping to reduce the time to market,

Figure 12.2 - Beneficial services distribution on cloud stack

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13 . CHALLENGES & THREATS The virtualization technologies that underlie the cloud computing infrastructures pose challenges on enforcing security policy when we have a sense of ambiguity concerning the actual physical properties of the resources.

While the cloud offers several advantages, until

some of the risks are better understood. Some threats & challenges posed to service providers as follows:

13.1 Challenges •

Data and security: If the organization uses a cloud based solution, it should

maintain its own data backups in addition to those saved by the cloud provider. Authentication credential management poses another cloud security concern. For example, Amazon provides IaaS services through its elastic cloud computing (EC2). These account holders receive public-key credentials for connecting to the servers but due to only one set of credentials per account. This makes it difficult to run applications in multiple places. •

SaaS concerns: With SaaS, users must rely heavilyon their cloud providers for

security. the provider must protect the underlying infrastructure from break-ins and generally has responsibility for all authentication and encryption. •

PaaS concerns: With PaaS, the provider might give some control to the people

building applications atop its platform. •

IaaS concerns: With IaaS, the developer has much better control over the

security environment, primarily because applications run on virtual machines. Backing up data poses another concern. Even though some providers do their own backups for the customer, much can still go wrong.

13.2 Threats • Use of cloud computing means dependence on others and that could possibly limit

flexibility and innovation. Security could prove to be a big issue. It is still unclear how safe outsourced data is and when using these services ownership of data is not always clear.

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• There are also issues relating to policy and access. What happens if the remote server goes

down? How will you then access files?

14. SUMMARY AND CONCLUSION

Cloud computing is a new and promising paradigm delivering IT services as computing utilities. As Clouds are designed to provide services to external users, providers need to be compensated for sharing their resources and capabilities. In this paper, we have proposed architecture for market-oriented allocation of resources within Clouds. We have discussed some representative platforms for Cloud computing covering the state-of-the-art. We have also presented a vision for the creation of global Cloud exchange for trading services. Cloud computing represents an exciting opportunity to bring on-demand applications to customers in an environment of reduced risk and enhanced reliability. However, it is important to understand that existing applications cannot just be unleashed on the cloud as is. Careful attention to design will help ensure a successful deployment. In particular, cloudbased applications should be deployed as virtual appliances so they contain all the components needed to operate, update, and manage them. Simple design will aid with scalability as demand for the application increases. And, planning for failure will ensure that the worst doesn’t happen when the inevitable occurs. Don’t be afraid to have your head in the clouds when it comes to application deployment. Your customers will reap the benefits, and you’ll gain the competitive advantage of a flexible, scalable application solution.

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